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android / toolchain / jdk / jdk9_langtools / 634d783489d29692e1223867204f761e219ef7a3 / . / src / share / classes / com / sun / tools / javac / comp / Check.java
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/*
* Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.sun.tools.javac.comp;
import java.util.*;
import javax.tools.JavaFileManager;
import com.sun.tools.javac.code.*;
import com.sun.tools.javac.code.Attribute.Compound;
import com.sun.tools.javac.jvm.*;
import com.sun.tools.javac.tree.*;
import com.sun.tools.javac.util.*;
import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
import com.sun.tools.javac.util.List;
import com.sun.tools.javac.code.Lint;
import com.sun.tools.javac.code.Lint.LintCategory;
import com.sun.tools.javac.code.Type.*;
import com.sun.tools.javac.code.Symbol.*;
import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
import com.sun.tools.javac.comp.Infer.InferenceContext;
import com.sun.tools.javac.comp.Infer.FreeTypeListener;
import com.sun.tools.javac.tree.JCTree.*;
import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
import static com.sun.tools.javac.code.Flags.*;
import static com.sun.tools.javac.code.Flags.ANNOTATION;
import static com.sun.tools.javac.code.Flags.SYNCHRONIZED;
import static com.sun.tools.javac.code.Kinds.*;
import static com.sun.tools.javac.code.TypeTag.*;
import static com.sun.tools.javac.code.TypeTag.WILDCARD;
import static com.sun.tools.javac.tree.JCTree.Tag.*;
/** Type checking helper class for the attribution phase.
*
* <p><b>This is NOT part of any supported API.
* If you write code that depends on this, you do so at your own risk.
* This code and its internal interfaces are subject to change or
* deletion without notice.</b>
*/
public class Check {
protected static final Context.Key<Check> checkKey = new Context.Key<>();
private final Names names;
private final Log log;
private final Resolve rs;
private final Symtab syms;
private final Enter enter;
private final DeferredAttr deferredAttr;
private final Infer infer;
private final Types types;
private final JCDiagnostic.Factory diags;
private boolean warnOnSyntheticConflicts;
private boolean suppressAbortOnBadClassFile;
private boolean enableSunApiLintControl;
private final TreeInfo treeinfo;
private final JavaFileManager fileManager;
private final Profile profile;
private final boolean warnOnAccessToSensitiveMembers;
// The set of lint options currently in effect. It is initialized
// from the context, and then is set/reset as needed by Attr as it
// visits all the various parts of the trees during attribution.
private Lint lint;
// The method being analyzed in Attr - it is set/reset as needed by
// Attr as it visits new method declarations.
private MethodSymbol method;
public static Check instance(Context context) {
Check instance = context.get(checkKey);
if (instance == null)
instance = new Check(context);
return instance;
}
protected Check(Context context) {
context.put(checkKey, this);
names = Names.instance(context);
dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE,
names.FIELD, names.METHOD, names.CONSTRUCTOR,
names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER};
log = Log.instance(context);
rs = Resolve.instance(context);
syms = Symtab.instance(context);
enter = Enter.instance(context);
deferredAttr = DeferredAttr.instance(context);
infer = Infer.instance(context);
types = Types.instance(context);
diags = JCDiagnostic.Factory.instance(context);
Options options = Options.instance(context);
lint = Lint.instance(context);
treeinfo = TreeInfo.instance(context);
fileManager = context.get(JavaFileManager.class);
Source source = Source.instance(context);
allowGenerics = source.allowGenerics();
allowVarargs = source.allowVarargs();
allowAnnotations = source.allowAnnotations();
allowCovariantReturns = source.allowCovariantReturns();
allowSimplifiedVarargs = source.allowSimplifiedVarargs();
allowDefaultMethods = source.allowDefaultMethods();
allowStrictMethodClashCheck = source.allowStrictMethodClashCheck();
complexInference = options.isSet("complexinference");
warnOnSyntheticConflicts = options.isSet("warnOnSyntheticConflicts");
suppressAbortOnBadClassFile = options.isSet("suppressAbortOnBadClassFile");
enableSunApiLintControl = options.isSet("enableSunApiLintControl");
warnOnAccessToSensitiveMembers = options.isSet("warnOnAccessToSensitiveMembers");
Target target = Target.instance(context);
syntheticNameChar = target.syntheticNameChar();
profile = Profile.instance(context);
boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
boolean verboseSunApi = lint.isEnabled(LintCategory.SUNAPI);
boolean enforceMandatoryWarnings = source.enforceMandatoryWarnings();
deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated,
enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION);
uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked,
enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED);
sunApiHandler = new MandatoryWarningHandler(log, verboseSunApi,
enforceMandatoryWarnings, "sunapi", null);
deferredLintHandler = DeferredLintHandler.instance(context);
}
/** Switch: generics enabled?
*/
boolean allowGenerics;
/** Switch: varargs enabled?
*/
boolean allowVarargs;
/** Switch: annotations enabled?
*/
boolean allowAnnotations;
/** Switch: covariant returns enabled?
*/
boolean allowCovariantReturns;
/** Switch: simplified varargs enabled?
*/
boolean allowSimplifiedVarargs;
/** Switch: default methods enabled?
*/
boolean allowDefaultMethods;
/** Switch: should unrelated return types trigger a method clash?
*/
boolean allowStrictMethodClashCheck;
/** Switch: -complexinference option set?
*/
boolean complexInference;
/** Character for synthetic names
*/
char syntheticNameChar;
/** A table mapping flat names of all compiled classes in this run to their
* symbols; maintained from outside.
*/
public Map<Name,ClassSymbol> compiled = new HashMap<>();
/** A handler for messages about deprecated usage.
*/
private MandatoryWarningHandler deprecationHandler;
/** A handler for messages about unchecked or unsafe usage.
*/
private MandatoryWarningHandler uncheckedHandler;
/** A handler for messages about using proprietary API.
*/
private MandatoryWarningHandler sunApiHandler;
/** A handler for deferred lint warnings.
*/
private DeferredLintHandler deferredLintHandler;
/* *************************************************************************
* Errors and Warnings
**************************************************************************/
Lint setLint(Lint newLint) {
Lint prev = lint;
lint = newLint;
return prev;
}
MethodSymbol setMethod(MethodSymbol newMethod) {
MethodSymbol prev = method;
method = newMethod;
return prev;
}
/** Warn about deprecated symbol.
* @param pos Position to be used for error reporting.
* @param sym The deprecated symbol.
*/
void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
if (!lint.isSuppressed(LintCategory.DEPRECATION))
deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location());
}
/** Warn about unchecked operation.
* @param pos Position to be used for error reporting.
* @param msg A string describing the problem.
*/
public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) {
if (!lint.isSuppressed(LintCategory.UNCHECKED))
uncheckedHandler.report(pos, msg, args);
}
/** Warn about unsafe vararg method decl.
* @param pos Position to be used for error reporting.
*/
void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) {
if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs)
log.warning(LintCategory.VARARGS, pos, key, args);
}
/** Warn about using proprietary API.
* @param pos Position to be used for error reporting.
* @param msg A string describing the problem.
*/
public void warnSunApi(DiagnosticPosition pos, String msg, Object... args) {
if (!lint.isSuppressed(LintCategory.SUNAPI))
sunApiHandler.report(pos, msg, args);
}
public void warnStatic(DiagnosticPosition pos, String msg, Object... args) {
if (lint.isEnabled(LintCategory.STATIC))
log.warning(LintCategory.STATIC, pos, msg, args);
}
/**
* Report any deferred diagnostics.
*/
public void reportDeferredDiagnostics() {
deprecationHandler.reportDeferredDiagnostic();
uncheckedHandler.reportDeferredDiagnostic();
sunApiHandler.reportDeferredDiagnostic();
}
/** Report a failure to complete a class.
* @param pos Position to be used for error reporting.
* @param ex The failure to report.
*/
public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue());
if (ex instanceof ClassFinder.BadClassFile
&& !suppressAbortOnBadClassFile) throw new Abort();
else return syms.errType;
}
/** Report an error that wrong type tag was found.
* @param pos Position to be used for error reporting.
* @param required An internationalized string describing the type tag
* required.
* @param found The type that was found.
*/
Type typeTagError(DiagnosticPosition pos, Object required, Object found) {
// this error used to be raised by the parser,
// but has been delayed to this point:
if (found instanceof Type && ((Type)found).hasTag(VOID)) {
log.error(pos, "illegal.start.of.type");
return syms.errType;
}
log.error(pos, "type.found.req", found, required);
return types.createErrorType(found instanceof Type ? (Type)found : syms.errType);
}
/** Report an error that symbol cannot be referenced before super
* has been called.
* @param pos Position to be used for error reporting.
* @param sym The referenced symbol.
*/
void earlyRefError(DiagnosticPosition pos, Symbol sym) {
log.error(pos, "cant.ref.before.ctor.called", sym);
}
/** Report duplicate declaration error.
*/
void duplicateError(DiagnosticPosition pos, Symbol sym) {
if (!sym.type.isErroneous()) {
Symbol location = sym.location();
if (location.kind == MTH &&
((MethodSymbol)location).isStaticOrInstanceInit()) {
log.error(pos, "already.defined.in.clinit", kindName(sym), sym,
kindName(sym.location()), kindName(sym.location().enclClass()),
sym.location().enclClass());
} else {
log.error(pos, "already.defined", kindName(sym), sym,
kindName(sym.location()), sym.location());
}
}
}
/** Report array/varargs duplicate declaration
*/
void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
log.error(pos, "array.and.varargs", sym1, sym2, sym2.location());
}
}
/* ************************************************************************
* duplicate declaration checking
*************************************************************************/
/** Check that variable does not hide variable with same name in
* immediately enclosing local scope.
* @param pos Position for error reporting.
* @param v The symbol.
* @param s The scope.
*/
void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
if (s.next != null) {
for (Scope.Entry e = s.next.lookup(v.name);
e.scope != null && e.sym.owner == v.owner;
e = e.next()) {
if (e.sym.kind == VAR &&
(e.sym.owner.kind & (VAR | MTH)) != 0 &&
v.name != names.error) {
duplicateError(pos, e.sym);
return;
}
}
}
}
/** Check that a class or interface does not hide a class or
* interface with same name in immediately enclosing local scope.
* @param pos Position for error reporting.
* @param c The symbol.
* @param s The scope.
*/
void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
if (s.next != null) {
for (Scope.Entry e = s.next.lookup(c.name);
e.scope != null && e.sym.owner == c.owner;
e = e.next()) {
if (e.sym.kind == TYP && !e.sym.type.hasTag(TYPEVAR) &&
(e.sym.owner.kind & (VAR | MTH)) != 0 &&
c.name != names.error) {
duplicateError(pos, e.sym);
return;
}
}
}
}
/** Check that class does not have the same name as one of
* its enclosing classes, or as a class defined in its enclosing scope.
* return true if class is unique in its enclosing scope.
* @param pos Position for error reporting.
* @param name The class name.
* @param s The enclosing scope.
*/
boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) {
if (e.sym.kind == TYP && e.sym.name != names.error) {
duplicateError(pos, e.sym);
return false;
}
}
for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
duplicateError(pos, sym);
return true;
}
}
return true;
}
/* *************************************************************************
* Class name generation
**************************************************************************/
/** Return name of local class.
* This is of the form {@code <enclClass> $ n <classname> }
* where
* enclClass is the flat name of the enclosing class,
* classname is the simple name of the local class
*/
Name localClassName(ClassSymbol c) {
for (int i=1; ; i++) {
Name flatname = names.
fromString("" + c.owner.enclClass().flatname +
syntheticNameChar + i +
c.name);
if (compiled.get(flatname) == null) return flatname;
}
}
public void newRound() {
compiled.clear();
}
/* *************************************************************************
* Type Checking
**************************************************************************/
/**
* A check context is an object that can be used to perform compatibility
* checks - depending on the check context, meaning of 'compatibility' might
* vary significantly.
*/
public interface CheckContext {
/**
* Is type 'found' compatible with type 'req' in given context
*/
boolean compatible(Type found, Type req, Warner warn);
/**
* Report a check error
*/
void report(DiagnosticPosition pos, JCDiagnostic details);
/**
* Obtain a warner for this check context
*/
public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
public Infer.InferenceContext inferenceContext();
public DeferredAttr.DeferredAttrContext deferredAttrContext();
}
/**
* This class represent a check context that is nested within another check
* context - useful to check sub-expressions. The default behavior simply
* redirects all method calls to the enclosing check context leveraging
* the forwarding pattern.
*/
static class NestedCheckContext implements CheckContext {
CheckContext enclosingContext;
NestedCheckContext(CheckContext enclosingContext) {
this.enclosingContext = enclosingContext;
}
public boolean compatible(Type found, Type req, Warner warn) {
return enclosingContext.compatible(found, req, warn);
}
public void report(DiagnosticPosition pos, JCDiagnostic details) {
enclosingContext.report(pos, details);
}
public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
return enclosingContext.checkWarner(pos, found, req);
}
public Infer.InferenceContext inferenceContext() {
return enclosingContext.inferenceContext();
}
public DeferredAttrContext deferredAttrContext() {
return enclosingContext.deferredAttrContext();
}
}
/**
* Check context to be used when evaluating assignment/return statements
*/
CheckContext basicHandler = new CheckContext() {
public void report(DiagnosticPosition pos, JCDiagnostic details) {
log.error(pos, "prob.found.req", details);
}
public boolean compatible(Type found, Type req, Warner warn) {
return types.isAssignable(found, req, warn);
}
public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
return convertWarner(pos, found, req);
}
public InferenceContext inferenceContext() {
return infer.emptyContext;
}
public DeferredAttrContext deferredAttrContext() {
return deferredAttr.emptyDeferredAttrContext;
}
@Override
public String toString() {
return "CheckContext: basicHandler";
}
};
/** Check that a given type is assignable to a given proto-type.
* If it is, return the type, otherwise return errType.
* @param pos Position to be used for error reporting.
* @param found The type that was found.
* @param req The type that was required.
*/
Type checkType(DiagnosticPosition pos, Type found, Type req) {
return checkType(pos, found, req, basicHandler);
}
Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
final Infer.InferenceContext inferenceContext = checkContext.inferenceContext();
if (inferenceContext.free(req)) {
inferenceContext.addFreeTypeListener(List.of(req), new FreeTypeListener() {
@Override
public void typesInferred(InferenceContext inferenceContext) {
checkType(pos, inferenceContext.asInstType(found), inferenceContext.asInstType(req), checkContext);
}
});
}
if (req.hasTag(ERROR))
return req;
if (req.hasTag(NONE))
return found;
if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
return found;
} else {
if (found.isNumeric() && req.isNumeric()) {
checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req));
return types.createErrorType(found);
}
checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
return types.createErrorType(found);
}
}
/** Check that a given type can be cast to a given target type.
* Return the result of the cast.
* @param pos Position to be used for error reporting.
* @param found The type that is being cast.
* @param req The target type of the cast.
*/
Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
return checkCastable(pos, found, req, basicHandler);
}
Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
if (types.isCastable(found, req, castWarner(pos, found, req))) {
return req;
} else {
checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
return types.createErrorType(found);
}
}
/** Check for redundant casts (i.e. where source type is a subtype of target type)
* The problem should only be reported for non-292 cast
*/
public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) {
if (!tree.type.isErroneous()
&& types.isSameType(tree.expr.type, tree.clazz.type)
&& !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
&& !is292targetTypeCast(tree)) {
deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
@Override
public void report() {
if (lint.isEnabled(Lint.LintCategory.CAST))
log.warning(Lint.LintCategory.CAST,
tree.pos(), "redundant.cast", tree.expr.type);
}
});
}
}
//where
private boolean is292targetTypeCast(JCTypeCast tree) {
boolean is292targetTypeCast = false;
JCExpression expr = TreeInfo.skipParens(tree.expr);
if (expr.hasTag(APPLY)) {
JCMethodInvocation apply = (JCMethodInvocation)expr;
Symbol sym = TreeInfo.symbol(apply.meth);
is292targetTypeCast = sym != null &&
sym.kind == MTH &&
(sym.flags() & HYPOTHETICAL) != 0;
}
return is292targetTypeCast;
}
private static final boolean ignoreAnnotatedCasts = true;
/** Check that a type is within some bounds.
*
* Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
* type argument.
* @param a The type that should be bounded by bs.
* @param bound The bound.
*/
private boolean checkExtends(Type a, Type bound) {
if (a.isUnbound()) {
return true;
} else if (!a.hasTag(WILDCARD)) {
a = types.cvarUpperBound(a);
return types.isSubtype(a, bound);
} else if (a.isExtendsBound()) {
return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings);
} else if (a.isSuperBound()) {
return !types.notSoftSubtype(types.wildLowerBound(a), bound);
}
return true;
}
/** Check that type is different from 'void'.
* @param pos Position to be used for error reporting.
* @param t The type to be checked.
*/
Type checkNonVoid(DiagnosticPosition pos, Type t) {
if (t.hasTag(VOID)) {
log.error(pos, "void.not.allowed.here");
return types.createErrorType(t);
} else {
return t;
}
}
Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
return typeTagError(pos,
diags.fragment("type.req.class.array"),
asTypeParam(t));
} else {
return t;
}
}
/** Check that type is a class or interface type.
* @param pos Position to be used for error reporting.
* @param t The type to be checked.
*/
Type checkClassType(DiagnosticPosition pos, Type t) {
if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
return typeTagError(pos,
diags.fragment("type.req.class"),
asTypeParam(t));
} else {
return t;
}
}
//where
private Object asTypeParam(Type t) {
return (t.hasTag(TYPEVAR))
? diags.fragment("type.parameter", t)
: t;
}
/** Check that type is a valid qualifier for a constructor reference expression
*/
Type checkConstructorRefType(DiagnosticPosition pos, Type t) {
t = checkClassOrArrayType(pos, t);
if (t.hasTag(CLASS)) {
if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
log.error(pos, "abstract.cant.be.instantiated", t.tsym);
t = types.createErrorType(t);
} else if ((t.tsym.flags() & ENUM) != 0) {
log.error(pos, "enum.cant.be.instantiated");
t = types.createErrorType(t);
} else {
t = checkClassType(pos, t, true);
}
} else if (t.hasTag(ARRAY)) {
if (!types.isReifiable(((ArrayType)t).elemtype)) {
log.error(pos, "generic.array.creation");
t = types.createErrorType(t);
}
}
return t;
}
/** Check that type is a class or interface type.
* @param pos Position to be used for error reporting.
* @param t The type to be checked.
* @param noBounds True if type bounds are illegal here.
*/
Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
t = checkClassType(pos, t);
if (noBounds && t.isParameterized()) {
List<Type> args = t.getTypeArguments();
while (args.nonEmpty()) {
if (args.head.hasTag(WILDCARD))
return typeTagError(pos,
diags.fragment("type.req.exact"),
args.head);
args = args.tail;
}
}
return t;
}
/** Check that type is a reference type, i.e. a class, interface or array type
* or a type variable.
* @param pos Position to be used for error reporting.
* @param t The type to be checked.
*/
Type checkRefType(DiagnosticPosition pos, Type t) {
if (t.isReference())
return t;
else
return typeTagError(pos,
diags.fragment("type.req.ref"),
t);
}
/** Check that each type is a reference type, i.e. a class, interface or array type
* or a type variable.
* @param trees Original trees, used for error reporting.
* @param types The types to be checked.
*/
List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
List<JCExpression> tl = trees;
for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
l.head = checkRefType(tl.head.pos(), l.head);
tl = tl.tail;
}
return types;
}
/** Check that type is a null or reference type.
* @param pos Position to be used for error reporting.
* @param t The type to be checked.
*/
Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
if (t.isReference() || t.hasTag(BOT))
return t;
else
return typeTagError(pos,
diags.fragment("type.req.ref"),
t);
}
/** Check that flag set does not contain elements of two conflicting sets. s
* Return true if it doesn't.
* @param pos Position to be used for error reporting.
* @param flags The set of flags to be checked.
* @param set1 Conflicting flags set #1.
* @param set2 Conflicting flags set #2.
*/
boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
if ((flags & set1) != 0 && (flags & set2) != 0) {
log.error(pos,
"illegal.combination.of.modifiers",
asFlagSet(TreeInfo.firstFlag(flags & set1)),
asFlagSet(TreeInfo.firstFlag(flags & set2)));
return false;
} else
return true;
}
/** Check that usage of diamond operator is correct (i.e. diamond should not
* be used with non-generic classes or in anonymous class creation expressions)
*/
Type checkDiamond(JCNewClass tree, Type t) {
if (!TreeInfo.isDiamond(tree) ||
t.isErroneous()) {
return checkClassType(tree.clazz.pos(), t, true);
} else if (tree.def != null) {
log.error(tree.clazz.pos(),
"cant.apply.diamond.1",
t, diags.fragment("diamond.and.anon.class", t));
return types.createErrorType(t);
} else if (t.tsym.type.getTypeArguments().isEmpty()) {
log.error(tree.clazz.pos(),
"cant.apply.diamond.1",
t, diags.fragment("diamond.non.generic", t));
return types.createErrorType(t);
} else if (tree.typeargs != null &&
tree.typeargs.nonEmpty()) {
log.error(tree.clazz.pos(),
"cant.apply.diamond.1",
t, diags.fragment("diamond.and.explicit.params", t));
return types.createErrorType(t);
} else {
return t;
}
}
void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) {
MethodSymbol m = tree.sym;
if (!allowSimplifiedVarargs) return;
boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null;
Type varargElemType = null;
if (m.isVarArgs()) {
varargElemType = types.elemtype(tree.params.last().type);
}
if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) {
if (varargElemType != null) {
log.error(tree,
"varargs.invalid.trustme.anno",
syms.trustMeType.tsym,
diags.fragment("varargs.trustme.on.virtual.varargs", m));
} else {
log.error(tree,
"varargs.invalid.trustme.anno",
syms.trustMeType.tsym,
diags.fragment("varargs.trustme.on.non.varargs.meth", m));
}
} else if (hasTrustMeAnno && varargElemType != null &&
types.isReifiable(varargElemType)) {
warnUnsafeVararg(tree,
"varargs.redundant.trustme.anno",
syms.trustMeType.tsym,
diags.fragment("varargs.trustme.on.reifiable.varargs", varargElemType));
}
else if (!hasTrustMeAnno && varargElemType != null &&
!types.isReifiable(varargElemType)) {
warnUnchecked(tree.params.head.pos(), "unchecked.varargs.non.reifiable.type", varargElemType);
}
}
//where
private boolean isTrustMeAllowedOnMethod(Symbol s) {
return (s.flags() & VARARGS) != 0 &&
(s.isConstructor() ||
(s.flags() & (STATIC | FINAL)) != 0);
}
Type checkMethod(final Type mtype,
final Symbol sym,
final Env<AttrContext> env,
final List<JCExpression> argtrees,
final List<Type> argtypes,
final boolean useVarargs,
InferenceContext inferenceContext) {
// System.out.println("call : " + env.tree);
// System.out.println("method : " + owntype);
// System.out.println("actuals: " + argtypes);
if (inferenceContext.free(mtype)) {
inferenceContext.addFreeTypeListener(List.of(mtype), new FreeTypeListener() {
public void typesInferred(InferenceContext inferenceContext) {
checkMethod(inferenceContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, inferenceContext);
}
});
return mtype;
}
Type owntype = mtype;
List<Type> formals = owntype.getParameterTypes();
List<Type> nonInferred = sym.type.getParameterTypes();
if (nonInferred.length() != formals.length()) nonInferred = formals;
Type last = useVarargs ? formals.last() : null;
if (sym.name == names.init && sym.owner == syms.enumSym) {
formals = formals.tail.tail;
nonInferred = nonInferred.tail.tail;
}
List<JCExpression> args = argtrees;
if (args != null) {
//this is null when type-checking a method reference
while (formals.head != last) {
JCTree arg = args.head;
Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head);
assertConvertible(arg, arg.type, formals.head, warn);
args = args.tail;
formals = formals.tail;
nonInferred = nonInferred.tail;
}
if (useVarargs) {
Type varArg = types.elemtype(last);
while (args.tail != null) {
JCTree arg = args.head;
Warner warn = convertWarner(arg.pos(), arg.type, varArg);
assertConvertible(arg, arg.type, varArg, warn);
args = args.tail;
}
} else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS &&
allowVarargs) {
// non-varargs call to varargs method
Type varParam = owntype.getParameterTypes().last();
Type lastArg = argtypes.last();
if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
!types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
types.elemtype(varParam), varParam);
}
}
if (useVarargs) {
Type argtype = owntype.getParameterTypes().last();
if (!types.isReifiable(argtype) &&
(!allowSimplifiedVarargs ||
sym.attribute(syms.trustMeType.tsym) == null ||
!isTrustMeAllowedOnMethod(sym))) {
warnUnchecked(env.tree.pos(),
"unchecked.generic.array.creation",
argtype);
}
if ((sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) == 0) {
TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
}
}
PolyKind pkind = (sym.type.hasTag(FORALL) &&
sym.type.getReturnType().containsAny(((ForAll)sym.type).tvars)) ?
PolyKind.POLY : PolyKind.STANDALONE;
TreeInfo.setPolyKind(env.tree, pkind);
return owntype;
}
//where
private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
if (types.isConvertible(actual, formal, warn))
return;
if (formal.isCompound()
&& types.isSubtype(actual, types.supertype(formal))
&& types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
return;
}
/**
* Check that type 't' is a valid instantiation of a generic class
* (see JLS 4.5)
*
* @param t class type to be checked
* @return true if 't' is well-formed
*/
public boolean checkValidGenericType(Type t) {
return firstIncompatibleTypeArg(t) == null;
}
//WHERE
private Type firstIncompatibleTypeArg(Type type) {
List<Type> formals = type.tsym.type.allparams();
List<Type> actuals = type.allparams();
List<Type> args = type.getTypeArguments();
List<Type> forms = type.tsym.type.getTypeArguments();
ListBuffer<Type> bounds_buf = new ListBuffer<>();
// For matching pairs of actual argument types `a' and
// formal type parameters with declared bound `b' ...
while (args.nonEmpty() && forms.nonEmpty()) {
// exact type arguments needs to know their
// bounds (for upper and lower bound
// calculations). So we create new bounds where
// type-parameters are replaced with actuals argument types.
bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
args = args.tail;
forms = forms.tail;
}
args = type.getTypeArguments();
List<Type> tvars_cap = types.substBounds(formals,
formals,
types.capture(type).allparams());
while (args.nonEmpty() && tvars_cap.nonEmpty()) {
// Let the actual arguments know their bound
args.head.withTypeVar((TypeVar)tvars_cap.head);
args = args.tail;
tvars_cap = tvars_cap.tail;
}
args = type.getTypeArguments();
List<Type> bounds = bounds_buf.toList();
while (args.nonEmpty() && bounds.nonEmpty()) {
Type actual = args.head;
if (!isTypeArgErroneous(actual) &&
!bounds.head.isErroneous() &&
!checkExtends(actual, bounds.head)) {
return args.head;
}
args = args.tail;
bounds = bounds.tail;
}
args = type.getTypeArguments();
bounds = bounds_buf.toList();
for (Type arg : types.capture(type).getTypeArguments()) {
if (arg.hasTag(TYPEVAR) &&
arg.getUpperBound().isErroneous() &&
!bounds.head.isErroneous() &&
!isTypeArgErroneous(args.head)) {
return args.head;
}
bounds = bounds.tail;
args = args.tail;
}
return null;
}
//where
boolean isTypeArgErroneous(Type t) {
return isTypeArgErroneous.visit(t);
}
Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
public Boolean visitType(Type t, Void s) {
return t.isErroneous();
}
@Override
public Boolean visitTypeVar(TypeVar t, Void s) {
return visit(t.getUpperBound());
}
@Override
public Boolean visitCapturedType(CapturedType t, Void s) {
return visit(t.getUpperBound()) ||
visit(t.getLowerBound());
}
@Override
public Boolean visitWildcardType(WildcardType t, Void s) {
return visit(t.type);
}
};
/** Check that given modifiers are legal for given symbol and
* return modifiers together with any implicit modifiers for that symbol.
* Warning: we can't use flags() here since this method
* is called during class enter, when flags() would cause a premature
* completion.
* @param pos Position to be used for error reporting.
* @param flags The set of modifiers given in a definition.
* @param sym The defined symbol.
*/
long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
long mask;
long implicit = 0;
switch (sym.kind) {
case VAR:
if (TreeInfo.isReceiverParam(tree))
mask = ReceiverParamFlags;
else if (sym.owner.kind != TYP)
mask = LocalVarFlags;
else if ((sym.owner.flags_field & INTERFACE) != 0)
mask = implicit = InterfaceVarFlags;
else
mask = VarFlags;
break;
case MTH:
if (sym.name == names.init) {
if ((sym.owner.flags_field & ENUM) != 0) {
// enum constructors cannot be declared public or
// protected and must be implicitly or explicitly
// private
implicit = PRIVATE;
mask = PRIVATE;
} else
mask = ConstructorFlags;
} else if ((sym.owner.flags_field & INTERFACE) != 0) {
if ((sym.owner.flags_field & ANNOTATION) != 0) {
mask = AnnotationTypeElementMask;
implicit = PUBLIC | ABSTRACT;
} else if ((flags & (DEFAULT | STATIC)) != 0) {
mask = InterfaceMethodMask;
implicit = PUBLIC;
if ((flags & DEFAULT) != 0) {
implicit |= ABSTRACT;
}
} else {
mask = implicit = InterfaceMethodFlags;
}
} else {
mask = MethodFlags;
}
// Imply STRICTFP if owner has STRICTFP set.
if (((flags|implicit) & Flags.ABSTRACT) == 0 ||
((flags) & Flags.DEFAULT) != 0)
implicit |= sym.owner.flags_field & STRICTFP;
break;
case TYP:
if (sym.isLocal()) {
mask = LocalClassFlags;
if (sym.name.isEmpty()) { // Anonymous class
// JLS: Anonymous classes are final.
implicit |= FINAL;
}
if ((sym.owner.flags_field & STATIC) == 0 &&
(flags & ENUM) != 0)
log.error(pos, "enums.must.be.static");
} else if (sym.owner.kind == TYP) {
mask = MemberClassFlags;
if (sym.owner.owner.kind == PCK ||
(sym.owner.flags_field & STATIC) != 0)
mask |= STATIC;
else if ((flags & ENUM) != 0)
log.error(pos, "enums.must.be.static");
// Nested interfaces and enums are always STATIC (Spec ???)
if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC;
} else {
mask = ClassFlags;
}
// Interfaces are always ABSTRACT
if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
if ((flags & ENUM) != 0) {
// enums can't be declared abstract or final
mask &= ~(ABSTRACT | FINAL);
implicit |= implicitEnumFinalFlag(tree);
}
// Imply STRICTFP if owner has STRICTFP set.
implicit |= sym.owner.flags_field & STRICTFP;
break;
default:
throw new AssertionError();
}
long illegal = flags & ExtendedStandardFlags & ~mask;
if (illegal != 0) {
if ((illegal & INTERFACE) != 0) {
log.error(pos, "intf.not.allowed.here");
mask |= INTERFACE;
}
else {
log.error(pos,
"mod.not.allowed.here", asFlagSet(illegal));
}
}
else if ((sym.kind == TYP ||
// ISSUE: Disallowing abstract&private is no longer appropriate
// in the presence of inner classes. Should it be deleted here?
checkDisjoint(pos, flags,
ABSTRACT,
PRIVATE | STATIC | DEFAULT))
&&
checkDisjoint(pos, flags,
STATIC,
DEFAULT)
&&
checkDisjoint(pos, flags,
ABSTRACT | INTERFACE,
FINAL | NATIVE | SYNCHRONIZED)
&&
checkDisjoint(pos, flags,
PUBLIC,
PRIVATE | PROTECTED)
&&
checkDisjoint(pos, flags,
PRIVATE,
PUBLIC | PROTECTED)
&&
checkDisjoint(pos, flags,
FINAL,
VOLATILE)
&&
(sym.kind == TYP ||
checkDisjoint(pos, flags,
ABSTRACT | NATIVE,
STRICTFP))) {
// skip
}
return flags & (mask | ~ExtendedStandardFlags) | implicit;
}
/** Determine if this enum should be implicitly final.
*
* If the enum has no specialized enum contants, it is final.
*
* If the enum does have specialized enum contants, it is
* <i>not</i> final.
*/
private long implicitEnumFinalFlag(JCTree tree) {
if (!tree.hasTag(CLASSDEF)) return 0;
class SpecialTreeVisitor extends JCTree.Visitor {
boolean specialized;
SpecialTreeVisitor() {
this.specialized = false;
}
@Override
public void visitTree(JCTree tree) { /* no-op */ }
@Override
public void visitVarDef(JCVariableDecl tree) {
if ((tree.mods.flags & ENUM) != 0) {
if (tree.init instanceof JCNewClass &&
((JCNewClass) tree.init).def != null) {
specialized = true;
}
}
}
}
SpecialTreeVisitor sts = new SpecialTreeVisitor();
JCClassDecl cdef = (JCClassDecl) tree;
for (JCTree defs: cdef.defs) {
defs.accept(sts);
if (sts.specialized) return 0;
}
return FINAL;
}
/* *************************************************************************
* Type Validation
**************************************************************************/
/** Validate a type expression. That is,
* check that all type arguments of a parametric type are within
* their bounds. This must be done in a second phase after type attribution
* since a class might have a subclass as type parameter bound. E.g:
*
* <pre>{@code
* class B<A extends C> { ... }
* class C extends B<C> { ... }
* }</pre>
*
* and we can't make sure that the bound is already attributed because
* of possible cycles.
*
* Visitor method: Validate a type expression, if it is not null, catching
* and reporting any completion failures.
*/
void validate(JCTree tree, Env<AttrContext> env) {
validate(tree, env, true);
}
void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
new Validator(env).validateTree(tree, checkRaw, true);
}
/** Visitor method: Validate a list of type expressions.
*/
void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
validate(l.head, env);
}
/** A visitor class for type validation.
*/
class Validator extends JCTree.Visitor {
boolean checkRaw;
boolean isOuter;
Env<AttrContext> env;
Validator(Env<AttrContext> env) {
this.env = env;
}
@Override
public void visitTypeArray(JCArrayTypeTree tree) {
validateTree(tree.elemtype, checkRaw, isOuter);
}
@Override
public void visitTypeApply(JCTypeApply tree) {
if (tree.type.hasTag(CLASS)) {
List<JCExpression> args = tree.arguments;
List<Type> forms = tree.type.tsym.type.getTypeArguments();
Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
if (incompatibleArg != null) {
for (JCTree arg : tree.arguments) {
if (arg.type == incompatibleArg) {
log.error(arg, "not.within.bounds", incompatibleArg, forms.head);
}
forms = forms.tail;
}
}
forms = tree.type.tsym.type.getTypeArguments();
boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
// For matching pairs of actual argument types `a' and
// formal type parameters with declared bound `b' ...
while (args.nonEmpty() && forms.nonEmpty()) {
validateTree(args.head,
!(isOuter && is_java_lang_Class),
false);
args = args.tail;
forms = forms.tail;
}
// Check that this type is either fully parameterized, or
// not parameterized at all.
if (tree.type.getEnclosingType().isRaw())
log.error(tree.pos(), "improperly.formed.type.inner.raw.param");
if (tree.clazz.hasTag(SELECT))
visitSelectInternal((JCFieldAccess)tree.clazz);
}
}
@Override
public void visitTypeParameter(JCTypeParameter tree) {
validateTrees(tree.bounds, true, isOuter);
checkClassBounds(tree.pos(), tree.type);
}
@Override
public void visitWildcard(JCWildcard tree) {
if (tree.inner != null)
validateTree(tree.inner, true, isOuter);
}
@Override
public void visitSelect(JCFieldAccess tree) {
if (tree.type.hasTag(CLASS)) {
visitSelectInternal(tree);
// Check that this type is either fully parameterized, or
// not parameterized at all.
if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
log.error(tree.pos(), "improperly.formed.type.param.missing");
}
}
public void visitSelectInternal(JCFieldAccess tree) {
if (tree.type.tsym.isStatic() &&
tree.selected.type.isParameterized()) {
// The enclosing type is not a class, so we are
// looking at a static member type. However, the
// qualifying expression is parameterized.
log.error(tree.pos(), "cant.select.static.class.from.param.type");
} else {
// otherwise validate the rest of the expression
tree.selected.accept(this);
}
}
@Override
public void visitAnnotatedType(JCAnnotatedType tree) {
tree.underlyingType.accept(this);
}
@Override
public void visitTypeIdent(JCPrimitiveTypeTree that) {
if (that.type.hasTag(TypeTag.VOID)) {
log.error(that.pos(), "void.not.allowed.here");
}
super.visitTypeIdent(that);
}
/** Default visitor method: do nothing.
*/
@Override
public void visitTree(JCTree tree) {
}
public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
if (tree != null) {
boolean prevCheckRaw = this.checkRaw;
this.checkRaw = checkRaw;
this.isOuter = isOuter;
try {
tree.accept(this);
if (checkRaw)
checkRaw(tree, env);
} catch (CompletionFailure ex) {
completionError(tree.pos(), ex);
} finally {
this.checkRaw = prevCheckRaw;
}
}
}
public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
validateTree(l.head, checkRaw, isOuter);
}
}
void checkRaw(JCTree tree, Env<AttrContext> env) {
if (lint.isEnabled(LintCategory.RAW) &&
tree.type.hasTag(CLASS) &&
!TreeInfo.isDiamond(tree) &&
!withinAnonConstr(env) &&
tree.type.isRaw()) {
log.warning(LintCategory.RAW,
tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type);
}
}
//where
private boolean withinAnonConstr(Env<AttrContext> env) {
return env.enclClass.name.isEmpty() &&
env.enclMethod != null && env.enclMethod.name == names.init;
}
/* *************************************************************************
* Exception checking
**************************************************************************/
/* The following methods treat classes as sets that contain
* the class itself and all their subclasses
*/
/** Is given type a subtype of some of the types in given list?
*/
boolean subset(Type t, List<Type> ts) {
for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
if (types.isSubtype(t, l.head)) return true;
return false;
}
/** Is given type a subtype or supertype of
* some of the types in given list?
*/
boolean intersects(Type t, List<Type> ts) {
for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
return false;
}
/** Add type set to given type list, unless it is a subclass of some class
* in the list.
*/
List<Type> incl(Type t, List<Type> ts) {
return subset(t, ts) ? ts : excl(t, ts).prepend(t);
}
/** Remove type set from type set list.
*/
List<Type> excl(Type t, List<Type> ts) {
if (ts.isEmpty()) {
return ts;
} else {
List<Type> ts1 = excl(t, ts.tail);
if (types.isSubtype(ts.head, t)) return ts1;
else if (ts1 == ts.tail) return ts;
else return ts1.prepend(ts.head);
}
}
/** Form the union of two type set lists.
*/
List<Type> union(List<Type> ts1, List<Type> ts2) {
List<Type> ts = ts1;
for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
ts = incl(l.head, ts);
return ts;
}
/** Form the difference of two type lists.
*/
List<Type> diff(List<Type> ts1, List<Type> ts2) {
List<Type> ts = ts1;
for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
ts = excl(l.head, ts);
return ts;
}
/** Form the intersection of two type lists.
*/
public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
List<Type> ts = List.nil();
for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
if (subset(l.head, ts2)) ts = incl(l.head, ts);
for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
if (subset(l.head, ts1)) ts = incl(l.head, ts);
return ts;
}
/** Is exc an exception symbol that need not be declared?
*/
boolean isUnchecked(ClassSymbol exc) {
return
exc.kind == ERR ||
exc.isSubClass(syms.errorType.tsym, types) ||
exc.isSubClass(syms.runtimeExceptionType.tsym, types);
}
/** Is exc an exception type that need not be declared?
*/
boolean isUnchecked(Type exc) {
return
(exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
(exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
exc.hasTag(BOT);
}
/** Same, but handling completion failures.
*/
boolean isUnchecked(DiagnosticPosition pos, Type exc) {
try {
return isUnchecked(exc);
} catch (CompletionFailure ex) {
completionError(pos, ex);
return true;
}
}
/** Is exc handled by given exception list?
*/
boolean isHandled(Type exc, List<Type> handled) {
return isUnchecked(exc) || subset(exc, handled);
}
/** Return all exceptions in thrown list that are not in handled list.
* @param thrown The list of thrown exceptions.
* @param handled The list of handled exceptions.
*/
List<Type> unhandled(List<Type> thrown, List<Type> handled) {
List<Type> unhandled = List.nil();
for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
return unhandled;
}
/* *************************************************************************
* Overriding/Implementation checking
**************************************************************************/
/** The level of access protection given by a flag set,
* where PRIVATE is highest and PUBLIC is lowest.
*/
static int protection(long flags) {
switch ((short)(flags & AccessFlags)) {
case PRIVATE: return 3;
case PROTECTED: return 1;
default:
case PUBLIC: return 0;
case 0: return 2;
}
}
/** A customized "cannot override" error message.
* @param m The overriding method.
* @param other The overridden method.
* @return An internationalized string.
*/
Object cannotOverride(MethodSymbol m, MethodSymbol other) {
String key;
if ((other.owner.flags() & INTERFACE) == 0)
key = "cant.override";
else if ((m.owner.flags() & INTERFACE) == 0)
key = "cant.implement";
else
key = "clashes.with";
return diags.fragment(key, m, m.location(), other, other.location());
}
/** A customized "override" warning message.
* @param m The overriding method.
* @param other The overridden method.
* @return An internationalized string.
*/
Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
String key;
if ((other.owner.flags() & INTERFACE) == 0)
key = "unchecked.override";
else if ((m.owner.flags() & INTERFACE) == 0)
key = "unchecked.implement";
else
key = "unchecked.clash.with";
return diags.fragment(key, m, m.location(), other, other.location());
}
/** A customized "override" warning message.
* @param m The overriding method.
* @param other The overridden method.
* @return An internationalized string.
*/
Object varargsOverrides(MethodSymbol m, MethodSymbol other) {
String key;
if ((other.owner.flags() & INTERFACE) == 0)
key = "varargs.override";
else if ((m.owner.flags() & INTERFACE) == 0)
key = "varargs.implement";
else
key = "varargs.clash.with";
return diags.fragment(key, m, m.location(), other, other.location());
}
/** Check that this method conforms with overridden method 'other'.
* where `origin' is the class where checking started.
* Complications:
* (1) Do not check overriding of synthetic methods
* (reason: they might be final).
* todo: check whether this is still necessary.
* (2) Admit the case where an interface proxy throws fewer exceptions
* than the method it implements. Augment the proxy methods with the
* undeclared exceptions in this case.
* (3) When generics are enabled, admit the case where an interface proxy
* has a result type
* extended by the result type of the method it implements.
* Change the proxies result type to the smaller type in this case.
*
* @param tree The tree from which positions
* are extracted for errors.
* @param m The overriding method.
* @param other The overridden method.
* @param origin The class of which the overriding method
* is a member.
*/
void checkOverride(JCTree tree,
MethodSymbol m,
MethodSymbol other,
ClassSymbol origin) {
// Don't check overriding of synthetic methods or by bridge methods.
if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
return;
}
// Error if static method overrides instance method (JLS 8.4.6.2).
if ((m.flags() & STATIC) != 0 &&
(other.flags() & STATIC) == 0) {
log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static",
cannotOverride(m, other));
m.flags_field |= BAD_OVERRIDE;
return;
}
// Error if instance method overrides static or final
// method (JLS 8.4.6.1).
if ((other.flags() & FINAL) != 0 ||
(m.flags() & STATIC) == 0 &&
(other.flags() & STATIC) != 0) {
log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth",
cannotOverride(m, other),
asFlagSet(other.flags() & (FINAL | STATIC)));
m.flags_field |= BAD_OVERRIDE;
return;
}
if ((m.owner.flags() & ANNOTATION) != 0) {
// handled in validateAnnotationMethod
return;
}
// Error if overriding method has weaker access (JLS 8.4.6.3).
if ((origin.flags() & INTERFACE) == 0 &&
protection(m.flags()) > protection(other.flags())) {
log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access",
cannotOverride(m, other),
(other.flags() & AccessFlags) == 0 ?
"package" :
asFlagSet(other.flags() & AccessFlags));
m.flags_field |= BAD_OVERRIDE;
return;
}
Type mt = types.memberType(origin.type, m);
Type ot = types.memberType(origin.type, other);
// Error if overriding result type is different
// (or, in the case of generics mode, not a subtype) of
// overridden result type. We have to rename any type parameters
// before comparing types.
List<Type> mtvars = mt.getTypeArguments();
List<Type> otvars = ot.getTypeArguments();
Type mtres = mt.getReturnType();
Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
overrideWarner.clear();
boolean resultTypesOK =
types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
if (!resultTypesOK) {
if (!allowCovariantReturns &&
m.owner != origin &&
m.owner.isSubClass(other.owner, types)) {
// allow limited interoperability with covariant returns
} else {
log.error(TreeInfo.diagnosticPositionFor(m, tree),
"override.incompatible.ret",
cannotOverride(m, other),
mtres, otres);
m.flags_field |= BAD_OVERRIDE;
return;
}
} else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
"override.unchecked.ret",
uncheckedOverrides(m, other),
mtres, otres);
}
// Error if overriding method throws an exception not reported
// by overridden method.
List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
if (unhandledErased.nonEmpty()) {
log.error(TreeInfo.diagnosticPositionFor(m, tree),
"override.meth.doesnt.throw",
cannotOverride(m, other),
unhandledUnerased.head);
m.flags_field |= BAD_OVERRIDE;
return;
}
else if (unhandledUnerased.nonEmpty()) {
warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
"override.unchecked.thrown",
cannotOverride(m, other),
unhandledUnerased.head);
return;
}
// Optional warning if varargs don't agree
if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
&& lint.isEnabled(LintCategory.OVERRIDES)) {
log.warning(TreeInfo.diagnosticPositionFor(m, tree),
((m.flags() & Flags.VARARGS) != 0)
? "override.varargs.missing"
: "override.varargs.extra",
varargsOverrides(m, other));
}
// Warn if instance method overrides bridge method (compiler spec ??)
if ((other.flags() & BRIDGE) != 0) {
log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge",
uncheckedOverrides(m, other));
}
// Warn if a deprecated method overridden by a non-deprecated one.
if (!isDeprecatedOverrideIgnorable(other, origin)) {
Lint prevLint = setLint(lint.augment(m));
try {
checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other);
} finally {
setLint(prevLint);
}
}
}
// where
private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
// If the method, m, is defined in an interface, then ignore the issue if the method
// is only inherited via a supertype and also implemented in the supertype,
// because in that case, we will rediscover the issue when examining the method
// in the supertype.
// If the method, m, is not defined in an interface, then the only time we need to
// address the issue is when the method is the supertype implemementation: any other
// case, we will have dealt with when examining the supertype classes
ClassSymbol mc = m.enclClass();
Type st = types.supertype(origin.type);
if (!st.hasTag(CLASS))
return true;
MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
List<Type> intfs = types.interfaces(origin.type);
return (intfs.contains(mc.type) ? false : (stimpl != null));
}
else
return (stimpl != m);
}
// used to check if there were any unchecked conversions
Warner overrideWarner = new Warner();
/** Check that a class does not inherit two concrete methods
* with the same signature.
* @param pos Position to be used for error reporting.
* @param site The class type to be checked.
*/
public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
Type sup = types.supertype(site);
if (!sup.hasTag(CLASS)) return;
for (Type t1 = sup;
t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
t1 = types.supertype(t1)) {
for (Scope.Entry e1 = t1.tsym.members().elems;
e1 != null;
e1 = e1.sibling) {
Symbol s1 = e1.sym;
if (s1.kind != MTH ||
(s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
!s1.isInheritedIn(site.tsym, types) ||
((MethodSymbol)s1).implementation(site.tsym,
types,
true) != s1)
continue;
Type st1 = types.memberType(t1, s1);
int s1ArgsLength = st1.getParameterTypes().length();
if (st1 == s1.type) continue;
for (Type t2 = sup;
t2.hasTag(CLASS);
t2 = types.supertype(t2)) {
for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name);
e2.scope != null;
e2 = e2.next()) {
Symbol s2 = e2.sym;
if (s2 == s1 ||
s2.kind != MTH ||
(s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
s2.type.getParameterTypes().length() != s1ArgsLength ||
!s2.isInheritedIn(site.tsym, types) ||
((MethodSymbol)s2).implementation(site.tsym,
types,
true) != s2)
continue;
Type st2 = types.memberType(t2, s2);
if (types.overrideEquivalent(st1, st2))
log.error(pos, "concrete.inheritance.conflict",
s1, t1, s2, t2, sup);
}
}
}
}
}
/** Check that classes (or interfaces) do not each define an abstract
* method with same name and arguments but incompatible return types.
* @param pos Position to be used for error reporting.
* @param t1 The first argument type.
* @param t2 The second argument type.
*/
public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
Type t1,
Type t2) {
return checkCompatibleAbstracts(pos, t1, t2,
types.makeCompoundType(t1, t2));
}
public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
Type t1,
Type t2,
Type site) {
if ((site.tsym.flags() & COMPOUND) != 0) {
// special case for intersections: need to eliminate wildcards in supertypes
t1 = types.capture(t1);
t2 = types.capture(t2);
}
return firstIncompatibility(pos, t1, t2, site) == null;
}
/** Return the first method which is defined with same args
* but different return types in two given interfaces, or null if none
* exists.
* @param t1 The first type.
* @param t2 The second type.
* @param site The most derived type.
* @returns symbol from t2 that conflicts with one in t1.
*/
private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
Map<TypeSymbol,Type> interfaces1 = new HashMap<>();
closure(t1, interfaces1);
Map<TypeSymbol,Type> interfaces2;
if (t1 == t2)
interfaces2 = interfaces1;
else
closure(t2, interfaces1, interfaces2 = new HashMap<>());
for (Type t3 : interfaces1.values()) {
for (Type t4 : interfaces2.values()) {
Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
if (s != null) return s;
}
}
return null;
}
/** Compute all the supertypes of t, indexed by type symbol. */
private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
if (!t.hasTag(CLASS)) return;
if (typeMap.put(t.tsym, t) == null) {
closure(types.supertype(t), typeMap);
for (Type i : types.interfaces(t))
closure(i, typeMap);
}
}
/** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */
private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
if (!t.hasTag(CLASS)) return;
if (typesSkip.get(t.tsym) != null) return;
if (typeMap.put(t.tsym, t) == null) {
closure(types.supertype(t), typesSkip, typeMap);
for (Type i : types.interfaces(t))
closure(i, typesSkip, typeMap);
}
}
/** Return the first method in t2 that conflicts with a method from t1. */
private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) {
Symbol s1 = e1.sym;
Type st1 = null;
if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
(s1.flags() & SYNTHETIC) != 0) continue;
Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) {
Symbol s2 = e2.sym;
if (s1 == s2) continue;
if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
(s2.flags() & SYNTHETIC) != 0) continue;
if (st1 == null) st1 = types.memberType(t1, s1);
Type st2 = types.memberType(t2, s2);
if (types.overrideEquivalent(st1, st2)) {
List<Type> tvars1 = st1.getTypeArguments();
List<Type> tvars2 = st2.getTypeArguments();
Type rt1 = st1.getReturnType();
Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
boolean compat =
types.isSameType(rt1, rt2) ||
!rt1.isPrimitiveOrVoid() &&
!rt2.isPrimitiveOrVoid() &&
(types.covariantReturnType(rt1, rt2, types.noWarnings) ||
types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
checkCommonOverriderIn(s1,s2,site);
if (!compat) {
log.error(pos, "types.incompatible.diff.ret",
t1, t2, s2.name +
"(" + types.memberType(t2, s2).getParameterTypes() + ")");
return s2;
}
} else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
!checkCommonOverriderIn(s1, s2, site)) {
log.error(pos,
"name.clash.same.erasure.no.override",
s1, s1.location(),
s2, s2.location());
return s2;
}
}
}
return null;
}
//WHERE
boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
Map<TypeSymbol,Type> supertypes = new HashMap<>();
Type st1 = types.memberType(site, s1);
Type st2 = types.memberType(site, s2);
closure(site, supertypes);
for (Type t : supertypes.values()) {
for (Scope.Entry e = t.tsym.members().lookup(s1.name); e.scope != null; e = e.next()) {
Symbol s3 = e.sym;
if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
Type st3 = types.memberType(site,s3);
if (types.overrideEquivalent(st3, st1) &&
types.overrideEquivalent(st3, st2) &&
types.returnTypeSubstitutable(st3, st1) &&
types.returnTypeSubstitutable(st3, st2)) {
return true;
}
}
}
return false;
}
/** Check that a given method conforms with any method it overrides.
* @param tree The tree from which positions are extracted
* for errors.
* @param m The overriding method.
*/
void checkOverride(JCMethodDecl tree, MethodSymbol m) {
ClassSymbol origin = (ClassSymbol)m.owner;
if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name))
if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
log.error(tree.pos(), "enum.no.finalize");
return;
}
for (Type t = origin.type; t.hasTag(CLASS);
t = types.supertype(t)) {
if (t != origin.type) {
checkOverride(tree, t, origin, m);
}
for (Type t2 : types.interfaces(t)) {
checkOverride(tree, t2, origin, m);
}
}
if (m.attribute(syms.overrideType.tsym) != null && !isOverrider(m)) {
DiagnosticPosition pos = tree.pos();
for (JCAnnotation a : tree.getModifiers().annotations) {
if (a.annotationType.type.tsym == syms.overrideType.tsym) {
pos = a.pos();
break;
}
}
log.error(pos, "method.does.not.override.superclass");
}
}
void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
TypeSymbol c = site.tsym;
Scope.Entry e = c.members().lookup(m.name);
while (e.scope != null) {
if (m.overrides(e.sym, origin, types, false)) {
if ((e.sym.flags() & ABSTRACT) == 0) {
checkOverride(tree, m, (MethodSymbol)e.sym, origin);
}
}
e = e.next();
}
}
private Filter<Symbol> equalsHasCodeFilter = new Filter<Symbol>() {
public boolean accepts(Symbol s) {
return MethodSymbol.implementation_filter.accepts(s) &&
(s.flags() & BAD_OVERRIDE) == 0;
}
};
public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
ClassSymbol someClass) {
/* At present, annotations cannot possibly have a method that is override
* equivalent with Object.equals(Object) but in any case the condition is
* fine for completeness.
*/
if (someClass == (ClassSymbol)syms.objectType.tsym ||
someClass.isInterface() || someClass.isEnum() ||
(someClass.flags() & ANNOTATION) != 0 ||
(someClass.flags() & ABSTRACT) != 0) return;
//anonymous inner classes implementing interfaces need especial treatment
if (someClass.isAnonymous()) {
List<Type> interfaces = types.interfaces(someClass.type);
if (interfaces != null && !interfaces.isEmpty() &&
interfaces.head.tsym == syms.comparatorType.tsym) return;
}
checkClassOverrideEqualsAndHash(pos, someClass);
}
private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
ClassSymbol someClass) {
if (lint.isEnabled(LintCategory.OVERRIDES)) {
MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
.tsym.members().lookup(names.equals).sym;
MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
.tsym.members().lookup(names.hashCode).sym;
boolean overridesEquals = types.implementation(equalsAtObject,
someClass, false, equalsHasCodeFilter).owner == someClass;
boolean overridesHashCode = types.implementation(hashCodeAtObject,
someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
if (overridesEquals && !overridesHashCode) {
log.warning(LintCategory.OVERRIDES, pos,
"override.equals.but.not.hashcode", someClass);
}
}
}
private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
ClashFilter cf = new ClashFilter(origin.type);
return (cf.accepts(s1) &&
cf.accepts(s2) &&
types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
}
/** Check that all abstract members of given class have definitions.
* @param pos Position to be used for error reporting.
* @param c The class.
*/
void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
try {
MethodSymbol undef = firstUndef(c, c);
if (undef != null) {
if ((c.flags() & ENUM) != 0 &&
types.supertype(c.type).tsym == syms.enumSym &&
(c.flags() & FINAL) == 0) {
// add the ABSTRACT flag to an enum
c.flags_field |= ABSTRACT;
} else {
MethodSymbol undef1 =
new MethodSymbol(undef.flags(), undef.name,
types.memberType(c.type, undef), undef.owner);
log.error(pos, "does.not.override.abstract",
c, undef1, undef1.location());
}
}
} catch (CompletionFailure ex) {
completionError(pos, ex);
}
}
//where
/** Return first abstract member of class `c' that is not defined
* in `impl', null if there is none.
*/
private MethodSymbol firstUndef(ClassSymbol impl, ClassSymbol c) {
MethodSymbol undef = null;
// Do not bother to search in classes that are not abstract,
// since they cannot have abstract members.
if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) {
Scope s = c.members();
for (Scope.Entry e = s.elems;
undef == null && e != null;
e = e.sibling) {
if (e.sym.kind == MTH &&
(e.sym.flags() & (ABSTRACT|IPROXY|DEFAULT)) == ABSTRACT) {
MethodSymbol absmeth = (MethodSymbol)e.sym;
MethodSymbol implmeth = absmeth.implementation(impl, types, true);
if (implmeth == null || implmeth == absmeth) {
//look for default implementations
if (allowDefaultMethods) {
MethodSymbol prov = types.interfaceCandidates(impl.type, absmeth).head;
if (prov != null && prov.overrides(absmeth, impl, types, true)) {
implmeth = prov;
}
}
}
if (implmeth == null || implmeth == absmeth) {
undef = absmeth;
}
}
}
if (undef == null) {
Type st = types.supertype(c.type);
if (st.hasTag(CLASS))
undef = firstUndef(impl, (ClassSymbol)st.tsym);
}
for (List<Type> l = types.interfaces(c.type);
undef == null && l.nonEmpty();
l = l.tail) {
undef = firstUndef(impl, (ClassSymbol)l.head.tsym);
}
}
return undef;
}
void checkNonCyclicDecl(JCClassDecl tree) {
CycleChecker cc = new CycleChecker();
cc.scan(tree);
if (!cc.errorFound && !cc.partialCheck) {
tree.sym.flags_field |= ACYCLIC;
}
}
class CycleChecker extends TreeScanner {
List<Symbol> seenClasses = List.nil();
boolean errorFound = false;
boolean partialCheck = false;
private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
if (sym != null && sym.kind == TYP) {
Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
if (classEnv != null) {
DiagnosticSource prevSource = log.currentSource();
try {
log.useSource(classEnv.toplevel.sourcefile);
scan(classEnv.tree);
}
finally {
log.useSource(prevSource.getFile());
}
} else if (sym.kind == TYP) {
checkClass(pos, sym, List.<JCTree>nil());
}
} else {
//not completed yet
partialCheck = true;
}
}
@Override
public void visitSelect(JCFieldAccess tree) {
super.visitSelect(tree);
checkSymbol(tree.pos(), tree.sym);
}
@Override
public void visitIdent(JCIdent tree) {
checkSymbol(tree.pos(), tree.sym);
}
@Override
public void visitTypeApply(JCTypeApply tree) {
scan(tree.clazz);
}
@Override
public void visitTypeArray(JCArrayTypeTree tree) {
scan(tree.elemtype);
}
@Override
public void visitClassDef(JCClassDecl tree) {
List<JCTree> supertypes = List.nil();
if (tree.getExtendsClause() != null) {
supertypes = supertypes.prepend(tree.getExtendsClause());
}
if (tree.getImplementsClause() != null) {
for (JCTree intf : tree.getImplementsClause()) {
supertypes = supertypes.prepend(intf);
}
}
checkClass(tree.pos(), tree.sym, supertypes);
}
void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
if ((c.flags_field & ACYCLIC) != 0)
return;
if (seenClasses.contains(c)) {
errorFound = true;
noteCyclic(pos, (ClassSymbol)c);
} else if (!c.type.isErroneous()) {
try {
seenClasses = seenClasses.prepend(c);
if (c.type.hasTag(CLASS)) {
if (supertypes.nonEmpty()) {
scan(supertypes);
}
else {
ClassType ct = (ClassType)c.type;
if (ct.supertype_field == null ||
ct.interfaces_field == null) {
//not completed yet
partialCheck = true;
return;
}
checkSymbol(pos, ct.supertype_field.tsym);
for (Type intf : ct.interfaces_field) {
checkSymbol(pos, intf.tsym);
}
}
if (c.owner.kind == TYP) {
checkSymbol(pos, c.owner);
}
}
} finally {
seenClasses = seenClasses.tail;
}
}
}
}
/** Check for cyclic references. Issue an error if the
* symbol of the type referred to has a LOCKED flag set.
*
* @param pos Position to be used for error reporting.
* @param t The type referred to.
*/
void checkNonCyclic(DiagnosticPosition pos, Type t) {
checkNonCyclicInternal(pos, t);
}
void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
checkNonCyclic1(pos, t, List.<TypeVar>nil());
}
private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
final TypeVar tv;
if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
return;
if (seen.contains(t)) {
tv = (TypeVar)t;
tv.bound = types.createErrorType(t);
log.error(pos, "cyclic.inheritance", t);
} else if (t.hasTag(TYPEVAR)) {
tv = (TypeVar)t;
seen = seen.prepend(tv);
for (Type b : types.getBounds(tv))
checkNonCyclic1(pos, b, seen);
}
}
/** Check for cyclic references. Issue an error if the
* symbol of the type referred to has a LOCKED flag set.
*
* @param pos Position to be used for error reporting.
* @param t The type referred to.
* @returns True if the check completed on all attributed classes
*/
private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
boolean complete = true; // was the check complete?
//- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
Symbol c = t.tsym;
if ((c.flags_field & ACYCLIC) != 0) return true;
if ((c.flags_field & LOCKED) != 0) {
noteCyclic(pos, (ClassSymbol)c);
} else if (!c.type.isErroneous()) {
try {
c.flags_field |= LOCKED;
if (c.type.hasTag(CLASS)) {
ClassType clazz = (ClassType)c.type;
if (clazz.interfaces_field != null)
for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
complete &= checkNonCyclicInternal(pos, l.head);
if (clazz.supertype_field != null) {
Type st = clazz.supertype_field;
if (st != null && st.hasTag(CLASS))
complete &= checkNonCyclicInternal(pos, st);
}
if (c.owner.kind == TYP)
complete &= checkNonCyclicInternal(pos, c.owner.type);
}
} finally {
c.flags_field &= ~LOCKED;
}
}
if (complete)
complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null;
if (complete) c.flags_field |= ACYCLIC;
return complete;
}
/** Note that we found an inheritance cycle. */
private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
log.error(pos, "cyclic.inheritance", c);
for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
Type st = types.supertype(c.type);
if (st.hasTag(CLASS))
((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
c.type = types.createErrorType(c, c.type);
c.flags_field |= ACYCLIC;
}
/** Check that all methods which implement some
* method conform to the method they implement.
* @param tree The class definition whose members are checked.
*/
void checkImplementations(JCClassDecl tree) {
checkImplementations(tree, tree.sym, tree.sym);
}
//where
/** Check that all methods which implement some
* method in `ic' conform to the method they implement.
*/
void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
ClassSymbol lc = (ClassSymbol)l.head.tsym;
if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) {
for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) {
if (e.sym.kind == MTH &&
(e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
MethodSymbol absmeth = (MethodSymbol)e.sym;
MethodSymbol implmeth = absmeth.implementation(origin, types, false);
if (implmeth != null && implmeth != absmeth &&
(implmeth.owner.flags() & INTERFACE) ==
(origin.flags() & INTERFACE)) {
// don't check if implmeth is in a class, yet
// origin is an interface. This case arises only
// if implmeth is declared in Object. The reason is
// that interfaces really don't inherit from
// Object it's just that the compiler represents
// things that way.
checkOverride(tree, implmeth, absmeth, origin);
}
}
}
}
}
}
/** Check that all abstract methods implemented by a class are
* mutually compatible.
* @param pos Position to be used for error reporting.
* @param c The class whose interfaces are checked.
*/
void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
List<Type> supertypes = types.interfaces(c);
Type supertype = types.supertype(c);
if (supertype.hasTag(CLASS) &&
(supertype.tsym.flags() & ABSTRACT) != 0)
supertypes = supertypes.prepend(supertype);
for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
if (allowGenerics && !l.head.getTypeArguments().isEmpty() &&
!checkCompatibleAbstracts(pos, l.head, l.head, c))
return;
for (List<Type> m = supertypes; m != l; m = m.tail)
if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
return;
}
checkCompatibleConcretes(pos, c);
}
void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
for (Scope.Entry e = ct.tsym.members().lookup(sym.name); e.scope == ct.tsym.members(); e = e.next()) {
// VM allows methods and variables with differing types
if (sym.kind == e.sym.kind &&
types.isSameType(types.erasure(sym.type), types.erasure(e.sym.type)) &&
sym != e.sym &&
(sym.flags() & Flags.SYNTHETIC) != (e.sym.flags() & Flags.SYNTHETIC) &&
(sym.flags() & IPROXY) == 0 && (e.sym.flags() & IPROXY) == 0 &&
(sym.flags() & BRIDGE) == 0 && (e.sym.flags() & BRIDGE) == 0) {
syntheticError(pos, (e.sym.flags() & SYNTHETIC) == 0 ? e.sym : sym);
return;
}
}
}
}
/** Check that all non-override equivalent methods accessible from 'site'
* are mutually compatible (JLS 8.4.8/9.4.1).
*
* @param pos Position to be used for error reporting.
* @param site The class whose methods are checked.
* @param sym The method symbol to be checked.
*/
void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
ClashFilter cf = new ClashFilter(site);
//for each method m1 that is overridden (directly or indirectly)
//by method 'sym' in 'site'...
List<MethodSymbol> potentiallyAmbiguousList = List.nil();
boolean overridesAny = false;
for (Symbol m1 : types.membersClosure(site, false).getElementsByName(sym.name, cf)) {
if (!sym.overrides(m1, site.tsym, types, false)) {
if (m1 == sym) {
continue;
}
if (!overridesAny) {
potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1);
}
continue;
}
if (m1 != sym) {
overridesAny = true;
potentiallyAmbiguousList = List.nil();
}
//...check each method m2 that is a member of 'site'
for (Symbol m2 : types.membersClosure(site, false).getElementsByName(sym.name, cf)) {
if (m2 == m1) continue;
//if (i) the signature of 'sym' is not a subsignature of m1 (seen as
//a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) &&
types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
sym.flags_field |= CLASH;
String key = m1 == sym ?
"name.clash.same.erasure.no.override" :
"name.clash.same.erasure.no.override.1";
log.error(pos,
key,
sym, sym.location(),
m2, m2.location(),
m1, m1.location());
return;
}
}
}
if (!overridesAny) {
for (MethodSymbol m: potentiallyAmbiguousList) {
checkPotentiallyAmbiguousOverloads(pos, site, sym, m);
}
}
}
/** Check that all static methods accessible from 'site' are
* mutually compatible (JLS 8.4.8).
*
* @param pos Position to be used for error reporting.
* @param site The class whose methods are checked.
* @param sym The method symbol to be checked.
*/
void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
ClashFilter cf = new ClashFilter(site);
//for each method m1 that is a member of 'site'...
for (Symbol s : types.membersClosure(site, true).getElementsByName(sym.name, cf)) {
//if (i) the signature of 'sym' is not a subsignature of m1 (seen as
//a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck)) {
if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
log.error(pos,
"name.clash.same.erasure.no.hide",
sym, sym.location(),
s, s.location());
return;
} else {
checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s);
}
}
}
}
//where
private class ClashFilter implements Filter<Symbol> {
Type site;
ClashFilter(Type site) {
this.site = site;
}
boolean shouldSkip(Symbol s) {
return (s.flags() & CLASH) != 0 &&
s.owner == site.tsym;
}
public boolean accepts(Symbol s) {
return s.kind == MTH &&
(s.flags() & SYNTHETIC) == 0 &&
!shouldSkip(s) &&
s.isInheritedIn(site.tsym, types) &&
!s.isConstructor();
}
}
void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
for (Symbol m : types.membersClosure(site, false).getElements(dcf)) {
Assert.check(m.kind == MTH);
List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
if (prov.size() > 1) {
ListBuffer<Symbol> abstracts = new ListBuffer<>();
ListBuffer<Symbol> defaults = new ListBuffer<>();
for (MethodSymbol provSym : prov) {
if ((provSym.flags() & DEFAULT) != 0) {
defaults = defaults.append(provSym);
} else if ((provSym.flags() & ABSTRACT) != 0) {
abstracts = abstracts.append(provSym);
}
if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
//strong semantics - issue an error if two sibling interfaces
//have two override-equivalent defaults - or if one is abstract
//and the other is default
String errKey;
Symbol s1 = defaults.first();
Symbol s2;
if (defaults.size() > 1) {
errKey = "types.incompatible.unrelated.defaults";
s2 = defaults.toList().tail.head;
} else {
errKey = "types.incompatible.abstract.default";
s2 = abstracts.first();
}
log.error(pos, errKey,
Kinds.kindName(site.tsym), site,
m.name, types.memberType(site, m).getParameterTypes(),
s1.location(), s2.location());
break;
}
}
}
}
}
//where
private class DefaultMethodClashFilter implements Filter<Symbol> {
Type site;
DefaultMethodClashFilter(Type site) {
this.site = site;
}
public boolean accepts(Symbol s) {
return s.kind == MTH &&
(s.flags() & DEFAULT) != 0 &&
s.isInheritedIn(site.tsym, types) &&
!s.isConstructor();
}
}
/**
* Report warnings for potentially ambiguous method declarations. Two declarations
* are potentially ambiguous if they feature two unrelated functional interface
* in same argument position (in which case, a call site passing an implicit
* lambda would be ambiguous).
*/
void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site,
MethodSymbol msym1, MethodSymbol msym2) {
if (msym1 != msym2 &&
allowDefaultMethods &&
lint.isEnabled(LintCategory.OVERLOADS) &&
(msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 &&
(msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) {
Type mt1 = types.memberType(site, msym1);
Type mt2 = types.memberType(site, msym2);
//if both generic methods, adjust type variables
if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
}
//expand varargs methods if needed
int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
//if arities don't match, exit
if (args1.length() != args2.length()) return;
boolean potentiallyAmbiguous = false;
while (args1.nonEmpty() && args2.nonEmpty()) {
Type s = args1.head;
Type t = args2.head;
if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
types.findDescriptorType(s).getParameterTypes().length() > 0 &&
types.findDescriptorType(s).getParameterTypes().length() ==
types.findDescriptorType(t).getParameterTypes().length()) {
potentiallyAmbiguous = true;
} else {
break;
}
}
args1 = args1.tail;
args2 = args2.tail;
}
if (potentiallyAmbiguous) {
//we found two incompatible functional interfaces with same arity
//this means a call site passing an implicit lambda would be ambigiuous
msym1.flags_field |= POTENTIALLY_AMBIGUOUS;
msym2.flags_field |= POTENTIALLY_AMBIGUOUS;
log.warning(LintCategory.OVERLOADS, pos, "potentially.ambiguous.overload",
msym1, msym1.location(),
msym2, msym2.location());
return;
}
}
}
void checkElemAccessFromSerializableLambda(final JCTree tree) {
if (warnOnAccessToSensitiveMembers) {
Symbol sym = TreeInfo.symbol(tree);
if ((sym.kind & (VAR | MTH)) == 0) {
return;
}
if (sym.kind == VAR) {
if ((sym.flags() & PARAMETER) != 0 ||
sym.isLocal() ||
sym.name == names._this ||
sym.name == names._super) {
return;
}
}
if (!types.isSubtype(sym.owner.type, syms.serializableType) &&
isEffectivelyNonPublic(sym)) {
log.warning(tree.pos(),
"access.to.sensitive.member.from.serializable.element", sym);
}
}
}
private boolean isEffectivelyNonPublic(Symbol sym) {
if (sym.packge() == syms.rootPackage) {
return false;
}
while (sym.kind != Kinds.PCK) {
if ((sym.flags() & PUBLIC) == 0) {
return true;
}
sym = sym.owner;
}
return false;
}
/** Report a conflict between a user symbol and a synthetic symbol.
*/
private void syntheticError(DiagnosticPosition pos, Symbol sym) {
if (!sym.type.isErroneous()) {
if (warnOnSyntheticConflicts) {
log.warning(pos, "synthetic.name.conflict", sym, sym.location());
}
else {
log.error(pos, "synthetic.name.conflict", sym, sym.location());
}
}
}
/** Check that class c does not implement directly or indirectly
* the same parameterized interface with two different argument lists.
* @param pos Position to be used for error reporting.
* @param type The type whose interfaces are checked.
*/
void checkClassBounds(DiagnosticPosition pos, Type type) {
checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
}
//where
/** Enter all interfaces of type `type' into the hash table `seensofar'
* with their class symbol as key and their type as value. Make
* sure no class is entered with two different types.
*/
void checkClassBounds(DiagnosticPosition pos,
Map<TypeSymbol,Type> seensofar,
Type type) {
if (type.isErroneous()) return;
for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
Type it = l.head;
Type oldit = seensofar.put(it.tsym, it);
if (oldit != null) {
List<Type> oldparams = oldit.allparams();
List<Type> newparams = it.allparams();
if (!types.containsTypeEquivalent(oldparams, newparams))
log.error(pos, "cant.inherit.diff.arg",
it.tsym, Type.toString(oldparams),
Type.toString(newparams));
}
checkClassBounds(pos, seensofar, it);
}
Type st = types.supertype(type);
if (st != null) checkClassBounds(pos, seensofar, st);
}
/** Enter interface into into set.
* If it existed already, issue a "repeated interface" error.
*/
void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
if (its.contains(it))
log.error(pos, "repeated.interface");
else {
its.add(it);
}
}
/* *************************************************************************
* Check annotations
**************************************************************************/
/**
* Recursively validate annotations values
*/
void validateAnnotationTree(JCTree tree) {
class AnnotationValidator extends TreeScanner {
@Override
public void visitAnnotation(JCAnnotation tree) {
if (!tree.type.isErroneous()) {
super.visitAnnotation(tree);
validateAnnotation(tree);
}
}
}
tree.accept(new AnnotationValidator());
}
/**
* {@literal
* Annotation types are restricted to primitives, String, an
* enum, an annotation, Class, Class<?>, Class<? extends
* Anything>, arrays of the preceding.
* }
*/
void validateAnnotationType(JCTree restype) {
// restype may be null if an error occurred, so don't bother validating it
if (restype != null) {
validateAnnotationType(restype.pos(), restype.type);
}
}
void validateAnnotationType(DiagnosticPosition pos, Type type) {
if (type.isPrimitive()) return;
if (types.isSameType(type, syms.stringType)) return;
if ((type.tsym.flags() & Flags.ENUM) != 0) return;
if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
validateAnnotationType(pos, types.elemtype(type));
return;
}
log.error(pos, "invalid.annotation.member.type");
}
/**
* "It is also a compile-time error if any method declared in an
* annotation type has a signature that is override-equivalent to
* that of any public or protected method declared in class Object
* or in the interface annotation.Annotation."
*
* @jls 9.6 Annotation Types
*/
void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
Scope s = sup.tsym.members();
for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) {
if (e.sym.kind == MTH &&
(e.sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
types.overrideEquivalent(m.type, e.sym.type))
log.error(pos, "intf.annotation.member.clash", e.sym, sup);
}
}
}
/** Check the annotations of a symbol.
*/
public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) {
for (JCAnnotation a : annotations)
validateAnnotation(a, s);
}
/** Check the type annotations.
*/
public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) {
for (JCAnnotation a : annotations)
validateTypeAnnotation(a, isTypeParameter);
}
/** Check an annotation of a symbol.
*/
private void validateAnnotation(JCAnnotation a, Symbol s) {
validateAnnotationTree(a);
if (!annotationApplicable(a, s))
log.error(a.pos(), "annotation.type.not.applicable");
if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
if (s.kind != TYP) {
log.error(a.pos(), "bad.functional.intf.anno");
} else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
log.error(a.pos(), "bad.functional.intf.anno.1", diags.fragment("not.a.functional.intf", s));
}
}
}
public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
Assert.checkNonNull(a.type, "annotation tree hasn't been attributed yet: " + a);
validateAnnotationTree(a);
if (a.hasTag(TYPE_ANNOTATION) &&
!a.annotationType.type.isErroneous() &&
!isTypeAnnotation(a, isTypeParameter)) {
log.error(a.pos(), "annotation.type.not.applicable");
}
}
/**
* Validate the proposed container 'repeatable' on the
* annotation type symbol 's'. Report errors at position
* 'pos'.
*
* @param s The (annotation)type declaration annotated with a @Repeatable
* @param repeatable the @Repeatable on 's'
* @param pos where to report errors
*/
public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
Type t = null;
List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
if (!l.isEmpty()) {
Assert.check(l.head.fst.name == names.value);
t = ((Attribute.Class)l.head.snd).getValue();
}
if (t == null) {
// errors should already have been reported during Annotate
return;
}
validateValue(t.tsym, s, pos);
validateRetention(t.tsym, s, pos);
validateDocumented(t.tsym, s, pos);
validateInherited(t.tsym, s, pos);
validateTarget(t.tsym, s, pos);
validateDefault(t.tsym, pos);
}
private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
Scope.Entry e = container.members().lookup(names.value);
if (e.scope != null && e.sym.kind == MTH) {
MethodSymbol m = (MethodSymbol) e.sym;
Type ret = m.getReturnType();
if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
log.error(pos, "invalid.repeatable.annotation.value.return",
container, ret, types.makeArrayType(contained.type));
}
} else {
log.error(pos, "invalid.repeatable.annotation.no.value", container);
}
}
private void validateRetention(Symbol container, Symbol contained, DiagnosticPosition pos) {
Attribute.RetentionPolicy containerRetention = types.getRetention(container);
Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
boolean error = false;
switch (containedRetention) {
case RUNTIME:
if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
error = true;
}
break;
case CLASS:
if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
error = true;
}
}
if (error ) {
log.error(pos, "invalid.repeatable.annotation.retention",
container, containerRetention,
contained, containedRetention);
}
}
private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
if (contained.attribute(syms.documentedType.tsym) != null) {
if (container.attribute(syms.documentedType.tsym) == null) {
log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained);
}
}
}
private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
if (contained.attribute(syms.inheritedType.tsym) != null) {
if (container.attribute(syms.inheritedType.tsym) == null) {
log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained);
}
}
}
private void validateTarget(Symbol container, Symbol contained, DiagnosticPosition pos) {
// The set of targets the container is applicable to must be a subset
// (with respect to annotation target semantics) of the set of targets
// the contained is applicable to. The target sets may be implicit or
// explicit.
Set<Name> containerTargets;
Attribute.Array containerTarget = getAttributeTargetAttribute(container);
if (containerTarget == null) {
containerTargets = getDefaultTargetSet();
} else {
containerTargets = new HashSet<>();
for (Attribute app : containerTarget.values) {
if (!(app instanceof Attribute.Enum)) {
continue; // recovery
}
Attribute.Enum e = (Attribute.Enum)app;
containerTargets.add(e.value.name);
}
}
Set<Name> containedTargets;
Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
if (containedTarget == null) {
containedTargets = getDefaultTargetSet();
} else {
containedTargets = new HashSet<>();
for (Attribute app : containedTarget.values) {
if (!(app instanceof Attribute.Enum)) {
continue; // recovery
}
Attribute.Enum e = (Attribute.Enum)app;
containedTargets.add(e.value.name);
}
}
if (!isTargetSubsetOf(containerTargets, containedTargets)) {
log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained);
}
}
/* get a set of names for the default target */
private Set<Name> getDefaultTargetSet() {
if (defaultTargets == null) {
Set<Name> targets = new HashSet<>();
targets.add(names.ANNOTATION_TYPE);
targets.add(names.CONSTRUCTOR);
targets.add(names.FIELD);
targets.add(names.LOCAL_VARIABLE);
targets.add(names.METHOD);
targets.add(names.PACKAGE);
targets.add(names.PARAMETER);
targets.add(names.TYPE);
defaultTargets = java.util.Collections.unmodifiableSet(targets);
}
return defaultTargets;
}
private Set<Name> defaultTargets;
/** Checks that s is a subset of t, with respect to ElementType
* semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
* and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
* TYPE_PARAMETER}.
*/
private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
// Check that all elements in s are present in t
for (Name n2 : s) {
boolean currentElementOk = false;
for (Name n1 : t) {
if (n1 == n2) {
currentElementOk = true;
break;
} else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
currentElementOk = true;
break;
} else if (n1 == names.TYPE_USE &&
(n2 == names.TYPE ||
n2 == names.ANNOTATION_TYPE ||
n2 == names.TYPE_PARAMETER)) {
currentElementOk = true;
break;
}
}
if (!currentElementOk)
return false;
}
return true;
}
private void validateDefault(Symbol container, DiagnosticPosition pos) {
// validate that all other elements of containing type has defaults
Scope scope = container.members();
for(Symbol elm : scope.getElements()) {
if (elm.name != names.value &&
elm.kind == Kinds.MTH &&
((MethodSymbol)elm).defaultValue == null) {
log.error(pos,
"invalid.repeatable.annotation.elem.nondefault",
container,
elm);
}
}
}
/** Is s a method symbol that overrides a method in a superclass? */
boolean isOverrider(Symbol s) {
if (s.kind != MTH || s.isStatic())
return false;
MethodSymbol m = (MethodSymbol)s;
TypeSymbol owner = (TypeSymbol)m.owner;
for (Type sup : types.closure(owner.type)) {
if (sup == owner.type)
continue; // skip "this"
Scope scope = sup.tsym.members();
for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) {
if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true))
return true;
}
}
return false;
}
/** Is the annotation applicable to types? */
protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
Attribute.Compound atTarget =
a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym);
if (atTarget == null) {
// An annotation without @Target is not a type annotation.
return false;
}
Attribute atValue = atTarget.member(names.value);
if (!(atValue instanceof Attribute.Array)) {
return false; // error recovery
}
Attribute.Array arr = (Attribute.Array) atValue;
for (Attribute app : arr.values) {
if (!(app instanceof Attribute.Enum)) {
return false; // recovery
}
Attribute.Enum e = (Attribute.Enum) app;
if (e.value.name == names.TYPE_USE)
return true;
else if (isTypeParameter && e.value.name == names.TYPE_PARAMETER)
return true;
}
return false;
}
/** Is the annotation applicable to the symbol? */
boolean annotationApplicable(JCAnnotation a, Symbol s) {
Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
Name[] targets;
if (arr == null) {
targets = defaultTargetMetaInfo(a, s);
} else {
// TODO: can we optimize this?
targets = new Name[arr.values.length];
for (int i=0; i<arr.values.length; ++i) {
Attribute app = arr.values[i];
if (!(app instanceof Attribute.Enum)) {
return true; // recovery
}
Attribute.Enum e = (Attribute.Enum) app;
targets[i] = e.value.name;
}
}
for (Name target : targets) {
if (target == names.TYPE)
{ if (s.kind == TYP) return true; }
else if (target == names.FIELD)
{ if (s.kind == VAR && s.owner.kind != MTH) return true; }
else if (target == names.METHOD)
{ if (s.kind == MTH && !s.isConstructor()) return true; }
else if (target == names.PARAMETER)
{ if (s.kind == VAR &&
s.owner.kind == MTH &&
(s.flags() & PARAMETER) != 0)
return true;
}
else if (target == names.CONSTRUCTOR)
{ if (s.kind == MTH && s.isConstructor()) return true; }
else if (target == names.LOCAL_VARIABLE)
{ if (s.kind == VAR && s.owner.kind == MTH &&
(s.flags() & PARAMETER) == 0)
return true;
}
else if (target == names.ANNOTATION_TYPE)
{ if (s.kind == TYP && (s.flags() & ANNOTATION) != 0)
return true;
}
else if (target == names.PACKAGE)
{ if (s.kind == PCK) return true; }
else if (target == names.TYPE_USE)
{ if (s.kind == TYP ||
s.kind == VAR ||
(s.kind == MTH && !s.isConstructor() &&
!s.type.getReturnType().hasTag(VOID)) ||
(s.kind == MTH && s.isConstructor()))
return true;
}
else if (target == names.TYPE_PARAMETER)
{ if (s.kind == TYP && s.type.hasTag(TYPEVAR))
return true;
}
else
return true; // recovery
}
return false;
}
Attribute.Array getAttributeTargetAttribute(Symbol s) {
Attribute.Compound atTarget =
s.attribute(syms.annotationTargetType.tsym);
if (atTarget == null) return null; // ok, is applicable
Attribute atValue = atTarget.member(names.value);
if (!(atValue instanceof Attribute.Array)) return null; // error recovery
return (Attribute.Array) atValue;
}
private final Name[] dfltTargetMeta;
private Name[] defaultTargetMetaInfo(JCAnnotation a, Symbol s) {
return dfltTargetMeta;
}
/** Check an annotation value.
*
* @param a The annotation tree to check
* @return true if this annotation tree is valid, otherwise false
*/
public boolean validateAnnotationDeferErrors(JCAnnotation a) {
boolean res = false;
final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
try {
res = validateAnnotation(a);
} finally {
log.popDiagnosticHandler(diagHandler);
}
return res;
}
private boolean validateAnnotation(JCAnnotation a) {
boolean isValid = true;
// collect an inventory of the annotation elements
Set<MethodSymbol> members = new LinkedHashSet<>();
for (Scope.Entry e = a.annotationType.type.tsym.members().elems;
e != null;
e = e.sibling)
if (e.sym.kind == MTH && e.sym.name != names.clinit &&
(e.sym.flags() & SYNTHETIC) == 0)
members.add((MethodSymbol) e.sym);
// remove the ones that are assigned values
for (JCTree arg : a.args) {
if (!arg.hasTag(ASSIGN)) continue; // recovery
JCAssign assign = (JCAssign) arg;
Symbol m = TreeInfo.symbol(assign.lhs);
if (m == null || m.type.isErroneous()) continue;
if (!members.remove(m)) {
isValid = false;
log.error(assign.lhs.pos(), "duplicate.annotation.member.value",
m.name, a.type);
}
}
// all the remaining ones better have default values
List<Name> missingDefaults = List.nil();
for (MethodSymbol m : members) {
if (m.defaultValue == null && !m.type.isErroneous()) {
missingDefaults = missingDefaults.append(m.name);
}
}
missingDefaults = missingDefaults.reverse();
if (missingDefaults.nonEmpty()) {
isValid = false;
String key = (missingDefaults.size() > 1)
? "annotation.missing.default.value.1"
: "annotation.missing.default.value";
log.error(a.pos(), key, a.type, missingDefaults);
}
// special case: java.lang.annotation.Target must not have
// repeated values in its value member
if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
a.args.tail == null)
return isValid;
if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
JCAssign assign = (JCAssign) a.args.head;
Symbol m = TreeInfo.symbol(assign.lhs);
if (m.name != names.value) return false;
JCTree rhs = assign.rhs;
if (!rhs.hasTag(NEWARRAY)) return false;
JCNewArray na = (JCNewArray) rhs;
Set<Symbol> targets = new HashSet<>();
for (JCTree elem : na.elems) {
if (!targets.add(TreeInfo.symbol(elem))) {
isValid = false;
log.error(elem.pos(), "repeated.annotation.target");
}
}
return isValid;
}
void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
if (allowAnnotations &&
lint.isEnabled(LintCategory.DEP_ANN) &&
(s.flags() & DEPRECATED) != 0 &&
!syms.deprecatedType.isErroneous() &&
s.attribute(syms.deprecatedType.tsym) == null) {
log.warning(LintCategory.DEP_ANN,
pos, "missing.deprecated.annotation");
}
}
void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
if ((s.flags() & DEPRECATED) != 0 &&
(other.flags() & DEPRECATED) == 0 &&
s.outermostClass() != other.outermostClass()) {
deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
@Override
public void report() {
warnDeprecated(pos, s);
}
});
}
}
void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
if ((s.flags() & PROPRIETARY) != 0) {
deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
public void report() {
if (enableSunApiLintControl)
warnSunApi(pos, "sun.proprietary", s);
else
log.mandatoryWarning(pos, "sun.proprietary", s);
}
});
}
}
void checkProfile(final DiagnosticPosition pos, final Symbol s) {
if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
log.error(pos, "not.in.profile", s, profile);
}
}
/* *************************************************************************
* Check for recursive annotation elements.
**************************************************************************/
/** Check for cycles in the graph of annotation elements.
*/
void checkNonCyclicElements(JCClassDecl tree) {
if ((tree.sym.flags_field & ANNOTATION) == 0) return;
Assert.check((tree.sym.flags_field & LOCKED) == 0);
try {
tree.sym.flags_field |= LOCKED;
for (JCTree def : tree.defs) {
if (!def.hasTag(METHODDEF)) continue;
JCMethodDecl meth = (JCMethodDecl)def;
checkAnnotationResType(meth.pos(), meth.restype.type);
}
} finally {
tree.sym.flags_field &= ~LOCKED;
tree.sym.flags_field |= ACYCLIC_ANN;
}
}
void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
if ((tsym.flags_field & ACYCLIC_ANN) != 0)
return;
if ((tsym.flags_field & LOCKED) != 0) {
log.error(pos, "cyclic.annotation.element");
return;
}
try {
tsym.flags_field |= LOCKED;
for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) {
Symbol s = e.sym;
if (s.kind != Kinds.MTH)
continue;
checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
}
} finally {
tsym.flags_field &= ~LOCKED;
tsym.flags_field |= ACYCLIC_ANN;
}
}
void checkAnnotationResType(DiagnosticPosition pos, Type type) {
switch (type.getTag()) {
case CLASS:
if ((type.tsym.flags() & ANNOTATION) != 0)
checkNonCyclicElementsInternal(pos, type.tsym);
break;
case ARRAY:
checkAnnotationResType(pos, types.elemtype(type));
break;
default:
break; // int etc
}
}
/* *************************************************************************
* Check for cycles in the constructor call graph.
**************************************************************************/
/** Check for cycles in the graph of constructors calling other
* constructors.
*/
void checkCyclicConstructors(JCClassDecl tree) {
Map<Symbol,Symbol> callMap = new HashMap<>();
// enter each constructor this-call into the map
for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
if (app == null) continue;
JCMethodDecl meth = (JCMethodDecl) l.head;
if (TreeInfo.name(app.meth) == names._this) {
callMap.put(meth.sym, TreeInfo.symbol(app.meth));
} else {
meth.sym.flags_field |= ACYCLIC;
}
}
// Check for cycles in the map
Symbol[] ctors = new Symbol[0];
ctors = callMap.keySet().toArray(ctors);
for (Symbol caller : ctors) {
checkCyclicConstructor(tree, caller, callMap);
}
}
/** Look in the map to see if the given constructor is part of a
* call cycle.
*/
private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
Map<Symbol,Symbol> callMap) {
if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
if ((ctor.flags_field & LOCKED) != 0) {
log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
"recursive.ctor.invocation");
} else {
ctor.flags_field |= LOCKED;
checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
ctor.flags_field &= ~LOCKED;
}
ctor.flags_field |= ACYCLIC;
}
}
/* *************************************************************************
* Miscellaneous
**************************************************************************/
/**
* Return the opcode of the operator but emit an error if it is an
* error.
* @param pos position for error reporting.
* @param operator an operator
* @param tag a tree tag
* @param left type of left hand side
* @param right type of right hand side
*/
int checkOperator(DiagnosticPosition pos,
OperatorSymbol operator,
JCTree.Tag tag,
Type left,
Type right) {
if (operator.opcode == ByteCodes.error) {
log.error(pos,
"operator.cant.be.applied.1",
treeinfo.operatorName(tag),
left, right);
}
return operator.opcode;
}
/**
* Check for division by integer constant zero
* @param pos Position for error reporting.
* @param operator The operator for the expression
* @param operand The right hand operand for the expression
*/
void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) {
if (operand.constValue() != null
&& lint.isEnabled(LintCategory.DIVZERO)
&& operand.getTag().isSubRangeOf(LONG)
&& ((Number) (operand.constValue())).longValue() == 0) {
int opc = ((OperatorSymbol)operator).opcode;
if (opc == ByteCodes.idiv || opc == ByteCodes.imod
|| opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
log.warning(LintCategory.DIVZERO, pos, "div.zero");
}
}
}
/**
* Check for empty statements after if
*/
void checkEmptyIf(JCIf tree) {
if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
lint.isEnabled(LintCategory.EMPTY))
log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if");
}
/** Check that symbol is unique in given scope.
* @param pos Position for error reporting.
* @param sym The symbol.
* @param s The scope.
*/
boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
if (sym.type.isErroneous())
return true;
if (sym.owner.name == names.any) return false;
for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) {
if (sym != e.sym &&
(e.sym.flags() & CLASH) == 0 &&
sym.kind == e.sym.kind &&
sym.name != names.error &&
(sym.kind != MTH ||
types.hasSameArgs(sym.type, e.sym.type) ||
types.hasSameArgs(types.erasure(sym.type), types.erasure(e.sym.type)))) {
if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS)) {
varargsDuplicateError(pos, sym, e.sym);
return true;
} else if (sym.kind == MTH && !types.hasSameArgs(sym.type, e.sym.type, false)) {
duplicateErasureError(pos, sym, e.sym);
sym.flags_field |= CLASH;
return true;
} else {
duplicateError(pos, e.sym);
return false;
}
}
}
return true;
}
/** Report duplicate declaration error.
*/
void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
log.error(pos, "name.clash.same.erasure", sym1, sym2);
}
}
/** Check that single-type import is not already imported or top-level defined,
* but make an exception for two single-type imports which denote the same type.
* @param pos Position for error reporting.
* @param sym The symbol.
* @param s The scope
*/
boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) {
return checkUniqueImport(pos, sym, s, false);
}
/** Check that static single-type import is not already imported or top-level defined,
* but make an exception for two single-type imports which denote the same type.
* @param pos Position for error reporting.
* @param sym The symbol.
* @param s The scope
*/
boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) {
return checkUniqueImport(pos, sym, s, true);
}
/** Check that single-type import is not already imported or top-level defined,
* but make an exception for two single-type imports which denote the same type.
* @param pos Position for error reporting.
* @param sym The symbol.
* @param s The scope.
* @param staticImport Whether or not this was a static import
*/
private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) {
for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) {
// is encountered class entered via a class declaration?
boolean isClassDecl = e.scope == s;
if ((isClassDecl || sym != e.sym) &&
sym.kind == e.sym.kind &&
sym.name != names.error &&
(!staticImport || !e.isStaticallyImported())) {
if (!e.sym.type.isErroneous()) {
if (!isClassDecl) {
if (staticImport)
log.error(pos, "already.defined.static.single.import", e.sym);
else
log.error(pos, "already.defined.single.import", e.sym);
}
else if (sym != e.sym)
log.error(pos, "already.defined.this.unit", e.sym);
}
return false;
}
}
return true;
}
/** Check that a qualified name is in canonical form (for import decls).
*/
public void checkCanonical(JCTree tree) {
if (!isCanonical(tree))
log.error(tree.pos(), "import.requires.canonical",
TreeInfo.symbol(tree));
}
// where
private boolean isCanonical(JCTree tree) {
while (tree.hasTag(SELECT)) {
JCFieldAccess s = (JCFieldAccess) tree;
if (s.sym.owner != TreeInfo.symbol(s.selected))
return false;
tree = s.selected;
}
return true;
}
/** Check that an auxiliary class is not accessed from any other file than its own.
*/
void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
(c.flags() & AUXILIARY) != 0 &&
rs.isAccessible(env, c) &&
!fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
{
log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file",
c, c.sourcefile);
}
}
private class ConversionWarner extends Warner {
final String uncheckedKey;
final Type found;
final Type expected;
public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
super(pos);
this.uncheckedKey = uncheckedKey;
this.found = found;
this.expected = expected;
}
@Override
public void warn(LintCategory lint) {
boolean warned = this.warned;
super.warn(lint);
if (warned) return; // suppress redundant diagnostics
switch (lint) {
case UNCHECKED:
Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected);
break;
case VARARGS:
if (method != null &&
method.attribute(syms.trustMeType.tsym) != null &&
isTrustMeAllowedOnMethod(method) &&
!types.isReifiable(method.type.getParameterTypes().last())) {
Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last());
}
break;
default:
throw new AssertionError("Unexpected lint: " + lint);
}
}
}
public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
}
public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
return new ConversionWarner(pos, "unchecked.assign", found, expected);
}
public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
if (functionalType != null) {
try {
types.findDescriptorSymbol((TypeSymbol)cs);
} catch (Types.FunctionDescriptorLookupError ex) {
DiagnosticPosition pos = tree.pos();
for (JCAnnotation a : tree.getModifiers().annotations) {
if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
pos = a.pos();
break;
}
}
log.error(pos, "bad.functional.intf.anno.1", ex.getDiagnostic());
}
}
}
}