Google Git
Sign in
android / platform / libcore / bd9526ecbe5 / . / langtools / src / share / classes / com / sun / tools / javac / comp / Resolve.java
blob: 301a3aeb44da5958f07e9043e1d4691f15e72558 [file] [log] [blame]
/*
* Copyright (c) 1999, 2011, 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 com.sun.tools.javac.util.*;
import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
import com.sun.tools.javac.code.*;
import com.sun.tools.javac.jvm.*;
import com.sun.tools.javac.tree.*;
import com.sun.tools.javac.api.Formattable.LocalizedString;
import static com.sun.tools.javac.comp.Resolve.MethodResolutionPhase.*;
import com.sun.tools.javac.code.Type.*;
import com.sun.tools.javac.code.Symbol.*;
import com.sun.tools.javac.tree.JCTree.*;
import static com.sun.tools.javac.code.Flags.*;
import static com.sun.tools.javac.code.Kinds.*;
import static com.sun.tools.javac.code.TypeTags.*;
import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
import com.sun.tools.javac.util.JCDiagnostic.DiagnosticType;
import javax.lang.model.element.ElementVisitor;
import java.util.Map;
import java.util.Set;
import java.util.HashMap;
import java.util.HashSet;
/** Helper class for name resolution, used mostly by 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 Resolve {
protected static final Context.Key<Resolve> resolveKey =
new Context.Key<Resolve>();
Names names;
Log log;
Symtab syms;
Check chk;
Infer infer;
ClassReader reader;
TreeInfo treeinfo;
Types types;
JCDiagnostic.Factory diags;
public final boolean boxingEnabled; // = source.allowBoxing();
public final boolean varargsEnabled; // = source.allowVarargs();
public final boolean allowMethodHandles;
private final boolean debugResolve;
Scope polymorphicSignatureScope;
public static Resolve instance(Context context) {
Resolve instance = context.get(resolveKey);
if (instance == null)
instance = new Resolve(context);
return instance;
}
protected Resolve(Context context) {
context.put(resolveKey, this);
syms = Symtab.instance(context);
varNotFound = new
SymbolNotFoundError(ABSENT_VAR);
wrongMethod = new
InapplicableSymbolError(syms.errSymbol);
wrongMethods = new
InapplicableSymbolsError(syms.errSymbol);
methodNotFound = new
SymbolNotFoundError(ABSENT_MTH);
typeNotFound = new
SymbolNotFoundError(ABSENT_TYP);
names = Names.instance(context);
log = Log.instance(context);
chk = Check.instance(context);
infer = Infer.instance(context);
reader = ClassReader.instance(context);
treeinfo = TreeInfo.instance(context);
types = Types.instance(context);
diags = JCDiagnostic.Factory.instance(context);
Source source = Source.instance(context);
boxingEnabled = source.allowBoxing();
varargsEnabled = source.allowVarargs();
Options options = Options.instance(context);
debugResolve = options.isSet("debugresolve");
Target target = Target.instance(context);
allowMethodHandles = target.hasMethodHandles();
polymorphicSignatureScope = new Scope(syms.noSymbol);
inapplicableMethodException = new InapplicableMethodException(diags);
}
/** error symbols, which are returned when resolution fails
*/
final SymbolNotFoundError varNotFound;
final InapplicableSymbolError wrongMethod;
final InapplicableSymbolsError wrongMethods;
final SymbolNotFoundError methodNotFound;
final SymbolNotFoundError typeNotFound;
/* ************************************************************************
* Identifier resolution
*************************************************************************/
/** An environment is "static" if its static level is greater than
* the one of its outer environment
*/
static boolean isStatic(Env<AttrContext> env) {
return env.info.staticLevel > env.outer.info.staticLevel;
}
/** An environment is an "initializer" if it is a constructor or
* an instance initializer.
*/
static boolean isInitializer(Env<AttrContext> env) {
Symbol owner = env.info.scope.owner;
return owner.isConstructor() ||
owner.owner.kind == TYP &&
(owner.kind == VAR ||
owner.kind == MTH && (owner.flags() & BLOCK) != 0) &&
(owner.flags() & STATIC) == 0;
}
/** Is class accessible in given evironment?
* @param env The current environment.
* @param c The class whose accessibility is checked.
*/
public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) {
return isAccessible(env, c, false);
}
public boolean isAccessible(Env<AttrContext> env, TypeSymbol c, boolean checkInner) {
boolean isAccessible = false;
switch ((short)(c.flags() & AccessFlags)) {
case PRIVATE:
isAccessible =
env.enclClass.sym.outermostClass() ==
c.owner.outermostClass();
break;
case 0:
isAccessible =
env.toplevel.packge == c.owner // fast special case
||
env.toplevel.packge == c.packge()
||
// Hack: this case is added since synthesized default constructors
// of anonymous classes should be allowed to access
// classes which would be inaccessible otherwise.
env.enclMethod != null &&
(env.enclMethod.mods.flags & ANONCONSTR) != 0;
break;
default: // error recovery
case PUBLIC:
isAccessible = true;
break;
case PROTECTED:
isAccessible =
env.toplevel.packge == c.owner // fast special case
||
env.toplevel.packge == c.packge()
||
isInnerSubClass(env.enclClass.sym, c.owner);
break;
}
return (checkInner == false || c.type.getEnclosingType() == Type.noType) ?
isAccessible :
isAccessible && isAccessible(env, c.type.getEnclosingType(), checkInner);
}
//where
/** Is given class a subclass of given base class, or an inner class
* of a subclass?
* Return null if no such class exists.
* @param c The class which is the subclass or is contained in it.
* @param base The base class
*/
private boolean isInnerSubClass(ClassSymbol c, Symbol base) {
while (c != null && !c.isSubClass(base, types)) {
c = c.owner.enclClass();
}
return c != null;
}
boolean isAccessible(Env<AttrContext> env, Type t) {
return isAccessible(env, t, false);
}
boolean isAccessible(Env<AttrContext> env, Type t, boolean checkInner) {
return (t.tag == ARRAY)
? isAccessible(env, types.elemtype(t))
: isAccessible(env, t.tsym, checkInner);
}
/** Is symbol accessible as a member of given type in given evironment?
* @param env The current environment.
* @param site The type of which the tested symbol is regarded
* as a member.
* @param sym The symbol.
*/
public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) {
return isAccessible(env, site, sym, false);
}
public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym, boolean checkInner) {
if (sym.name == names.init && sym.owner != site.tsym) return false;
switch ((short)(sym.flags() & AccessFlags)) {
case PRIVATE:
return
(env.enclClass.sym == sym.owner // fast special case
||
env.enclClass.sym.outermostClass() ==
sym.owner.outermostClass())
&&
sym.isInheritedIn(site.tsym, types);
case 0:
return
(env.toplevel.packge == sym.owner.owner // fast special case
||
env.toplevel.packge == sym.packge())
&&
isAccessible(env, site, checkInner)
&&
sym.isInheritedIn(site.tsym, types)
&&
notOverriddenIn(site, sym);
case PROTECTED:
return
(env.toplevel.packge == sym.owner.owner // fast special case
||
env.toplevel.packge == sym.packge()
||
isProtectedAccessible(sym, env.enclClass.sym, site)
||
// OK to select instance method or field from 'super' or type name
// (but type names should be disallowed elsewhere!)
env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
&&
isAccessible(env, site, checkInner)
&&
notOverriddenIn(site, sym);
default: // this case includes erroneous combinations as well
return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym);
}
}
//where
/* `sym' is accessible only if not overridden by
* another symbol which is a member of `site'
* (because, if it is overridden, `sym' is not strictly
* speaking a member of `site'). A polymorphic signature method
* cannot be overridden (e.g. MH.invokeExact(Object[])).
*/
private boolean notOverriddenIn(Type site, Symbol sym) {
if (sym.kind != MTH || sym.isConstructor() || sym.isStatic())
return true;
else {
Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true);
return (s2 == null || s2 == sym || sym.owner == s2.owner ||
s2.isPolymorphicSignatureGeneric() ||
!types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym)));
}
}
//where
/** Is given protected symbol accessible if it is selected from given site
* and the selection takes place in given class?
* @param sym The symbol with protected access
* @param c The class where the access takes place
* @site The type of the qualifier
*/
private
boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
while (c != null &&
!(c.isSubClass(sym.owner, types) &&
(c.flags() & INTERFACE) == 0 &&
// In JLS 2e 6.6.2.1, the subclass restriction applies
// only to instance fields and methods -- types are excluded
// regardless of whether they are declared 'static' or not.
((sym.flags() & STATIC) != 0 || sym.kind == TYP || site.tsym.isSubClass(c, types))))
c = c.owner.enclClass();
return c != null;
}
/** Try to instantiate the type of a method so that it fits
* given type arguments and argument types. If succesful, return
* the method's instantiated type, else return null.
* The instantiation will take into account an additional leading
* formal parameter if the method is an instance method seen as a member
* of un underdetermined site In this case, we treat site as an additional
* parameter and the parameters of the class containing the method as
* additional type variables that get instantiated.
*
* @param env The current environment
* @param site The type of which the method is a member.
* @param m The method symbol.
* @param argtypes The invocation's given value arguments.
* @param typeargtypes The invocation's given type arguments.
* @param allowBoxing Allow boxing conversions of arguments.
* @param useVarargs Box trailing arguments into an array for varargs.
*/
Type rawInstantiate(Env<AttrContext> env,
Type site,
Symbol m,
List<Type> argtypes,
List<Type> typeargtypes,
boolean allowBoxing,
boolean useVarargs,
Warner warn)
throws Infer.InferenceException {
boolean polymorphicSignature = m.isPolymorphicSignatureGeneric() && allowMethodHandles;
if (useVarargs && (m.flags() & VARARGS) == 0)
throw inapplicableMethodException.setMessage();
Type mt = types.memberType(site, m);
// tvars is the list of formal type variables for which type arguments
// need to inferred.
List<Type> tvars = null;
if (env.info.tvars != null) {
tvars = types.newInstances(env.info.tvars);
mt = types.subst(mt, env.info.tvars, tvars);
}
if (typeargtypes == null) typeargtypes = List.nil();
if (mt.tag != FORALL && typeargtypes.nonEmpty()) {
// This is not a polymorphic method, but typeargs are supplied
// which is fine, see JLS3 15.12.2.1
} else if (mt.tag == FORALL && typeargtypes.nonEmpty()) {
ForAll pmt = (ForAll) mt;
if (typeargtypes.length() != pmt.tvars.length())
throw inapplicableMethodException.setMessage("arg.length.mismatch"); // not enough args
// Check type arguments are within bounds
List<Type> formals = pmt.tvars;
List<Type> actuals = typeargtypes;
while (formals.nonEmpty() && actuals.nonEmpty()) {
List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
pmt.tvars, typeargtypes);
for (; bounds.nonEmpty(); bounds = bounds.tail)
if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn))
throw inapplicableMethodException.setMessage("explicit.param.do.not.conform.to.bounds",actuals.head, bounds);
formals = formals.tail;
actuals = actuals.tail;
}
mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
} else if (mt.tag == FORALL) {
ForAll pmt = (ForAll) mt;
List<Type> tvars1 = types.newInstances(pmt.tvars);
tvars = tvars.appendList(tvars1);
mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
}
// find out whether we need to go the slow route via infer
boolean instNeeded = tvars.tail != null || /*inlined: tvars.nonEmpty()*/
polymorphicSignature;
for (List<Type> l = argtypes;
l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
l = l.tail) {
if (l.head.tag == FORALL) instNeeded = true;
}
if (instNeeded)
return polymorphicSignature ?
infer.instantiatePolymorphicSignatureInstance(env, site, m.name, (MethodSymbol)m, argtypes) :
infer.instantiateMethod(env,
tvars,
(MethodType)mt,
m,
argtypes,
allowBoxing,
useVarargs,
warn);
checkRawArgumentsAcceptable(env, argtypes, mt.getParameterTypes(),
allowBoxing, useVarargs, warn);
return mt;
}
/** Same but returns null instead throwing a NoInstanceException
*/
Type instantiate(Env<AttrContext> env,
Type site,
Symbol m,
List<Type> argtypes,
List<Type> typeargtypes,
boolean allowBoxing,
boolean useVarargs,
Warner warn) {
try {
return rawInstantiate(env, site, m, argtypes, typeargtypes,
allowBoxing, useVarargs, warn);
} catch (InapplicableMethodException ex) {
return null;
}
}
/** Check if a parameter list accepts a list of args.
*/
boolean argumentsAcceptable(Env<AttrContext> env,
List<Type> argtypes,
List<Type> formals,
boolean allowBoxing,
boolean useVarargs,
Warner warn) {
try {
checkRawArgumentsAcceptable(env, argtypes, formals, allowBoxing, useVarargs, warn);
return true;
} catch (InapplicableMethodException ex) {
return false;
}
}
void checkRawArgumentsAcceptable(Env<AttrContext> env,
List<Type> argtypes,
List<Type> formals,
boolean allowBoxing,
boolean useVarargs,
Warner warn) {
Type varargsFormal = useVarargs ? formals.last() : null;
if (varargsFormal == null &&
argtypes.size() != formals.size()) {
throw inapplicableMethodException.setMessage("arg.length.mismatch"); // not enough args
}
while (argtypes.nonEmpty() && formals.head != varargsFormal) {
boolean works = allowBoxing
? types.isConvertible(argtypes.head, formals.head, warn)
: types.isSubtypeUnchecked(argtypes.head, formals.head, warn);
if (!works)
throw inapplicableMethodException.setMessage("no.conforming.assignment.exists",
argtypes.head,
formals.head);
argtypes = argtypes.tail;
formals = formals.tail;
}
if (formals.head != varargsFormal)
throw inapplicableMethodException.setMessage("arg.length.mismatch"); // not enough args
if (useVarargs) {
//note: if applicability check is triggered by most specific test,
//the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5)
Type elt = types.elemtypeOrType(varargsFormal);
while (argtypes.nonEmpty()) {
if (!types.isConvertible(argtypes.head, elt, warn))
throw inapplicableMethodException.setMessage("varargs.argument.mismatch",
argtypes.head,
elt);
argtypes = argtypes.tail;
}
//check varargs element type accessibility
if (!isAccessible(env, elt)) {
Symbol location = env.enclClass.sym;
throw inapplicableMethodException.setMessage("inaccessible.varargs.type",
elt,
Kinds.kindName(location),
location);
}
}
return;
}
// where
public static class InapplicableMethodException extends RuntimeException {
private static final long serialVersionUID = 0;
JCDiagnostic diagnostic;
JCDiagnostic.Factory diags;
InapplicableMethodException(JCDiagnostic.Factory diags) {
this.diagnostic = null;
this.diags = diags;
}
InapplicableMethodException setMessage() {
this.diagnostic = null;
return this;
}
InapplicableMethodException setMessage(String key) {
this.diagnostic = key != null ? diags.fragment(key) : null;
return this;
}
InapplicableMethodException setMessage(String key, Object... args) {
this.diagnostic = key != null ? diags.fragment(key, args) : null;
return this;
}
InapplicableMethodException setMessage(JCDiagnostic diag) {
this.diagnostic = diag;
return this;
}
public JCDiagnostic getDiagnostic() {
return diagnostic;
}
}
private final InapplicableMethodException inapplicableMethodException;
/* ***************************************************************************
* Symbol lookup
* the following naming conventions for arguments are used
*
* env is the environment where the symbol was mentioned
* site is the type of which the symbol is a member
* name is the symbol's name
* if no arguments are given
* argtypes are the value arguments, if we search for a method
*
* If no symbol was found, a ResolveError detailing the problem is returned.
****************************************************************************/
/** Find field. Synthetic fields are always skipped.
* @param env The current environment.
* @param site The original type from where the selection takes place.
* @param name The name of the field.
* @param c The class to search for the field. This is always
* a superclass or implemented interface of site's class.
*/
Symbol findField(Env<AttrContext> env,
Type site,
Name name,
TypeSymbol c) {
while (c.type.tag == TYPEVAR)
c = c.type.getUpperBound().tsym;
Symbol bestSoFar = varNotFound;
Symbol sym;
Scope.Entry e = c.members().lookup(name);
while (e.scope != null) {
if (e.sym.kind == VAR && (e.sym.flags_field & SYNTHETIC) == 0) {
return isAccessible(env, site, e.sym)
? e.sym : new AccessError(env, site, e.sym);
}
e = e.next();
}
Type st = types.supertype(c.type);
if (st != null && (st.tag == CLASS || st.tag == TYPEVAR)) {
sym = findField(env, site, name, st.tsym);
if (sym.kind < bestSoFar.kind) bestSoFar = sym;
}
for (List<Type> l = types.interfaces(c.type);
bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
l = l.tail) {
sym = findField(env, site, name, l.head.tsym);
if (bestSoFar.kind < AMBIGUOUS && sym.kind < AMBIGUOUS &&
sym.owner != bestSoFar.owner)
bestSoFar = new AmbiguityError(bestSoFar, sym);
else if (sym.kind < bestSoFar.kind)
bestSoFar = sym;
}
return bestSoFar;
}
/** Resolve a field identifier, throw a fatal error if not found.
* @param pos The position to use for error reporting.
* @param env The environment current at the method invocation.
* @param site The type of the qualifying expression, in which
* identifier is searched.
* @param name The identifier's name.
*/
public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
Type site, Name name) {
Symbol sym = findField(env, site, name, site.tsym);
if (sym.kind == VAR) return (VarSymbol)sym;
else throw new FatalError(
diags.fragment("fatal.err.cant.locate.field",
name));
}
/** Find unqualified variable or field with given name.
* Synthetic fields always skipped.
* @param env The current environment.
* @param name The name of the variable or field.
*/
Symbol findVar(Env<AttrContext> env, Name name) {
Symbol bestSoFar = varNotFound;
Symbol sym;
Env<AttrContext> env1 = env;
boolean staticOnly = false;
while (env1.outer != null) {
if (isStatic(env1)) staticOnly = true;
Scope.Entry e = env1.info.scope.lookup(name);
while (e.scope != null &&
(e.sym.kind != VAR ||
(e.sym.flags_field & SYNTHETIC) != 0))
e = e.next();
sym = (e.scope != null)
? e.sym
: findField(
env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
if (sym.exists()) {
if (staticOnly &&
sym.kind == VAR &&
sym.owner.kind == TYP &&
(sym.flags() & STATIC) == 0)
return new StaticError(sym);
else
return sym;
} else if (sym.kind < bestSoFar.kind) {
bestSoFar = sym;
}
if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
env1 = env1.outer;
}
sym = findField(env, syms.predefClass.type, name, syms.predefClass);
if (sym.exists())
return sym;
if (bestSoFar.exists())
return bestSoFar;
Scope.Entry e = env.toplevel.namedImportScope.lookup(name);
for (; e.scope != null; e = e.next()) {
sym = e.sym;
Type origin = e.getOrigin().owner.type;
if (sym.kind == VAR) {
if (e.sym.owner.type != origin)
sym = sym.clone(e.getOrigin().owner);
return isAccessible(env, origin, sym)
? sym : new AccessError(env, origin, sym);
}
}
Symbol origin = null;
e = env.toplevel.starImportScope.lookup(name);
for (; e.scope != null; e = e.next()) {
sym = e.sym;
if (sym.kind != VAR)
continue;
// invariant: sym.kind == VAR
if (bestSoFar.kind < AMBIGUOUS && sym.owner != bestSoFar.owner)
return new AmbiguityError(bestSoFar, sym);
else if (bestSoFar.kind >= VAR) {
origin = e.getOrigin().owner;
bestSoFar = isAccessible(env, origin.type, sym)
? sym : new AccessError(env, origin.type, sym);
}
}
if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
return bestSoFar.clone(origin);
else
return bestSoFar;
}
Warner noteWarner = new Warner();
/** Select the best method for a call site among two choices.
* @param env The current environment.
* @param site The original type from where the
* selection takes place.
* @param argtypes The invocation's value arguments,
* @param typeargtypes The invocation's type arguments,
* @param sym Proposed new best match.
* @param bestSoFar Previously found best match.
* @param allowBoxing Allow boxing conversions of arguments.
* @param useVarargs Box trailing arguments into an array for varargs.
*/
@SuppressWarnings("fallthrough")
Symbol selectBest(Env<AttrContext> env,
Type site,
List<Type> argtypes,
List<Type> typeargtypes,
Symbol sym,
Symbol bestSoFar,
boolean allowBoxing,
boolean useVarargs,
boolean operator) {
if (sym.kind == ERR) return bestSoFar;
if (!sym.isInheritedIn(site.tsym, types)) return bestSoFar;
Assert.check(sym.kind < AMBIGUOUS);
try {
rawInstantiate(env, site, sym, argtypes, typeargtypes,
allowBoxing, useVarargs, Warner.noWarnings);
} catch (InapplicableMethodException ex) {
switch (bestSoFar.kind) {
case ABSENT_MTH:
return wrongMethod.setWrongSym(sym, ex.getDiagnostic());
case WRONG_MTH:
wrongMethods.addCandidate(currentStep, wrongMethod.sym, wrongMethod.explanation);
case WRONG_MTHS:
return wrongMethods.addCandidate(currentStep, sym, ex.getDiagnostic());
default:
return bestSoFar;
}
}
if (!isAccessible(env, site, sym)) {
return (bestSoFar.kind == ABSENT_MTH)
? new AccessError(env, site, sym)
: bestSoFar;
}
return (bestSoFar.kind > AMBIGUOUS)
? sym
: mostSpecific(sym, bestSoFar, env, site,
allowBoxing && operator, useVarargs);
}
/* Return the most specific of the two methods for a call,
* given that both are accessible and applicable.
* @param m1 A new candidate for most specific.
* @param m2 The previous most specific candidate.
* @param env The current environment.
* @param site The original type from where the selection
* takes place.
* @param allowBoxing Allow boxing conversions of arguments.
* @param useVarargs Box trailing arguments into an array for varargs.
*/
Symbol mostSpecific(Symbol m1,
Symbol m2,
Env<AttrContext> env,
final Type site,
boolean allowBoxing,
boolean useVarargs) {
switch (m2.kind) {
case MTH:
if (m1 == m2) return m1;
boolean m1SignatureMoreSpecific = signatureMoreSpecific(env, site, m1, m2, allowBoxing, useVarargs);
boolean m2SignatureMoreSpecific = signatureMoreSpecific(env, site, m2, m1, allowBoxing, useVarargs);
if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
Type mt1 = types.memberType(site, m1);
Type mt2 = types.memberType(site, m2);
if (!types.overrideEquivalent(mt1, mt2))
return ambiguityError(m1, m2);
// same signature; select (a) the non-bridge method, or
// (b) the one that overrides the other, or (c) the concrete
// one, or (d) merge both abstract signatures
if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE))
return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
// if one overrides or hides the other, use it
TypeSymbol m1Owner = (TypeSymbol)m1.owner;
TypeSymbol m2Owner = (TypeSymbol)m2.owner;
if (types.asSuper(m1Owner.type, m2Owner) != null &&
((m1.owner.flags_field & INTERFACE) == 0 ||
(m2.owner.flags_field & INTERFACE) != 0) &&
m1.overrides(m2, m1Owner, types, false))
return m1;
if (types.asSuper(m2Owner.type, m1Owner) != null &&
((m2.owner.flags_field & INTERFACE) == 0 ||
(m1.owner.flags_field & INTERFACE) != 0) &&
m2.overrides(m1, m2Owner, types, false))
return m2;
boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
if (m1Abstract && !m2Abstract) return m2;
if (m2Abstract && !m1Abstract) return m1;
// both abstract or both concrete
if (!m1Abstract && !m2Abstract)
return ambiguityError(m1, m2);
// check that both signatures have the same erasure
if (!types.isSameTypes(m1.erasure(types).getParameterTypes(),
m2.erasure(types).getParameterTypes()))
return ambiguityError(m1, m2);
// both abstract, neither overridden; merge throws clause and result type
Symbol mostSpecific;
Type result2 = mt2.getReturnType();
if (mt2.tag == FORALL)
result2 = types.subst(result2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
if (types.isSubtype(mt1.getReturnType(), result2))
mostSpecific = m1;
else if (types.isSubtype(result2, mt1.getReturnType()))
mostSpecific = m2;
else {
// Theoretically, this can't happen, but it is possible
// due to error recovery or mixing incompatible class files
return ambiguityError(m1, m2);
}
List<Type> allThrown = chk.intersect(mt1.getThrownTypes(), mt2.getThrownTypes());
Type newSig = types.createMethodTypeWithThrown(mostSpecific.type, allThrown);
MethodSymbol result = new MethodSymbol(
mostSpecific.flags(),
mostSpecific.name,
newSig,
mostSpecific.owner) {
@Override
public MethodSymbol implementation(TypeSymbol origin, Types types, boolean checkResult) {
if (origin == site.tsym)
return this;
else
return super.implementation(origin, types, checkResult);
}
};
return result;
}
if (m1SignatureMoreSpecific) return m1;
if (m2SignatureMoreSpecific) return m2;
return ambiguityError(m1, m2);
case AMBIGUOUS:
AmbiguityError e = (AmbiguityError)m2;
Symbol err1 = mostSpecific(m1, e.sym, env, site, allowBoxing, useVarargs);
Symbol err2 = mostSpecific(m1, e.sym2, env, site, allowBoxing, useVarargs);
if (err1 == err2) return err1;
if (err1 == e.sym && err2 == e.sym2) return m2;
if (err1 instanceof AmbiguityError &&
err2 instanceof AmbiguityError &&
((AmbiguityError)err1).sym == ((AmbiguityError)err2).sym)
return ambiguityError(m1, m2);
else
return ambiguityError(err1, err2);
default:
throw new AssertionError();
}
}
//where
private boolean signatureMoreSpecific(Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean allowBoxing, boolean useVarargs) {
noteWarner.clear();
Type mtype1 = types.memberType(site, adjustVarargs(m1, m2, useVarargs));
return (instantiate(env, site, adjustVarargs(m2, m1, useVarargs), types.lowerBoundArgtypes(mtype1), null,
allowBoxing, false, noteWarner) != null ||
useVarargs && instantiate(env, site, adjustVarargs(m2, m1, useVarargs), types.lowerBoundArgtypes(mtype1), null,
allowBoxing, true, noteWarner) != null) &&
!noteWarner.hasLint(Lint.LintCategory.UNCHECKED);
}
//where
private Symbol adjustVarargs(Symbol to, Symbol from, boolean useVarargs) {
List<Type> fromArgs = from.type.getParameterTypes();
List<Type> toArgs = to.type.getParameterTypes();
if (useVarargs &&
(from.flags() & VARARGS) != 0 &&
(to.flags() & VARARGS) != 0) {
Type varargsTypeFrom = fromArgs.last();
Type varargsTypeTo = toArgs.last();
ListBuffer<Type> args = ListBuffer.lb();
if (toArgs.length() < fromArgs.length()) {
//if we are checking a varargs method 'from' against another varargs
//method 'to' (where arity of 'to' < arity of 'from') then expand signature
//of 'to' to 'fit' arity of 'from' (this means adding fake formals to 'to'
//until 'to' signature has the same arity as 'from')
while (fromArgs.head != varargsTypeFrom) {
args.append(toArgs.head == varargsTypeTo ? types.elemtype(varargsTypeTo) : toArgs.head);
fromArgs = fromArgs.tail;
toArgs = toArgs.head == varargsTypeTo ?
toArgs :
toArgs.tail;
}
} else {
//formal argument list is same as original list where last
//argument (array type) is removed
args.appendList(toArgs.reverse().tail.reverse());
}
//append varargs element type as last synthetic formal
args.append(types.elemtype(varargsTypeTo));
Type mtype = types.createMethodTypeWithParameters(to.type, args.toList());
return new MethodSymbol(to.flags_field, to.name, mtype, to.owner);
} else {
return to;
}
}
//where
Symbol ambiguityError(Symbol m1, Symbol m2) {
if (((m1.flags() | m2.flags()) & CLASH) != 0) {
return (m1.flags() & CLASH) == 0 ? m1 : m2;
} else {
return new AmbiguityError(m1, m2);
}
}
/** Find best qualified method matching given name, type and value
* arguments.
* @param env The current environment.
* @param site The original type from where the selection
* takes place.
* @param name The method's name.
* @param argtypes The method's value arguments.
* @param typeargtypes The method's type arguments
* @param allowBoxing Allow boxing conversions of arguments.
* @param useVarargs Box trailing arguments into an array for varargs.
*/
Symbol findMethod(Env<AttrContext> env,
Type site,
Name name,
List<Type> argtypes,
List<Type> typeargtypes,
boolean allowBoxing,
boolean useVarargs,
boolean operator) {
Symbol bestSoFar = methodNotFound;
return findMethod(env,
site,
name,
argtypes,
typeargtypes,
site.tsym.type,
true,
bestSoFar,
allowBoxing,
useVarargs,
operator,
new HashSet<TypeSymbol>());
}
// where
private Symbol findMethod(Env<AttrContext> env,
Type site,
Name name,
List<Type> argtypes,
List<Type> typeargtypes,
Type intype,
boolean abstractok,
Symbol bestSoFar,
boolean allowBoxing,
boolean useVarargs,
boolean operator,
Set<TypeSymbol> seen) {
for (Type ct = intype; ct.tag == CLASS || ct.tag == TYPEVAR; ct = types.supertype(ct)) {
while (ct.tag == TYPEVAR)
ct = ct.getUpperBound();
ClassSymbol c = (ClassSymbol)ct.tsym;
if (!seen.add(c)) return bestSoFar;
if ((c.flags() & (ABSTRACT | INTERFACE | ENUM)) == 0)
abstractok = false;
for (Scope.Entry e = c.members().lookup(name);
e.scope != null;
e = e.next()) {
//- System.out.println(" e " + e.sym);
if (e.sym.kind == MTH &&
(e.sym.flags_field & SYNTHETIC) == 0) {
bestSoFar = selectBest(env, site, argtypes, typeargtypes,
e.sym, bestSoFar,
allowBoxing,
useVarargs,
operator);
}
}
if (name == names.init)
break;
//- System.out.println(" - " + bestSoFar);
if (abstractok) {
Symbol concrete = methodNotFound;
if ((bestSoFar.flags() & ABSTRACT) == 0)
concrete = bestSoFar;
for (List<Type> l = types.interfaces(c.type);
l.nonEmpty();
l = l.tail) {
bestSoFar = findMethod(env, site, name, argtypes,
typeargtypes,
l.head, abstractok, bestSoFar,
allowBoxing, useVarargs, operator, seen);
}
if (concrete != bestSoFar &&
concrete.kind < ERR && bestSoFar.kind < ERR &&
types.isSubSignature(concrete.type, bestSoFar.type))
bestSoFar = concrete;
}
}
return bestSoFar;
}
/** Find unqualified method matching given name, type and value arguments.
* @param env The current environment.
* @param name The method's name.
* @param argtypes The method's value arguments.
* @param typeargtypes The method's type arguments.
* @param allowBoxing Allow boxing conversions of arguments.
* @param useVarargs Box trailing arguments into an array for varargs.
*/
Symbol findFun(Env<AttrContext> env, Name name,
List<Type> argtypes, List<Type> typeargtypes,
boolean allowBoxing, boolean useVarargs) {
Symbol bestSoFar = methodNotFound;
Symbol sym;
Env<AttrContext> env1 = env;
boolean staticOnly = false;
while (env1.outer != null) {
if (isStatic(env1)) staticOnly = true;
sym = findMethod(
env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
allowBoxing, useVarargs, false);
if (sym.exists()) {
if (staticOnly &&
sym.kind == MTH &&
sym.owner.kind == TYP &&
(sym.flags() & STATIC) == 0) return new StaticError(sym);
else return sym;
} else if (sym.kind < bestSoFar.kind) {
bestSoFar = sym;
}
if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
env1 = env1.outer;
}
sym = findMethod(env, syms.predefClass.type, name, argtypes,
typeargtypes, allowBoxing, useVarargs, false);
if (sym.exists())
return sym;
Scope.Entry e = env.toplevel.namedImportScope.lookup(name);
for (; e.scope != null; e = e.next()) {
sym = e.sym;
Type origin = e.getOrigin().owner.type;
if (sym.kind == MTH) {
if (e.sym.owner.type != origin)
sym = sym.clone(e.getOrigin().owner);
if (!isAccessible(env, origin, sym))
sym = new AccessError(env, origin, sym);
bestSoFar = selectBest(env, origin,
argtypes, typeargtypes,
sym, bestSoFar,
allowBoxing, useVarargs, false);
}
}
if (bestSoFar.exists())
return bestSoFar;
e = env.toplevel.starImportScope.lookup(name);
for (; e.scope != null; e = e.next()) {
sym = e.sym;
Type origin = e.getOrigin().owner.type;
if (sym.kind == MTH) {
if (e.sym.owner.type != origin)
sym = sym.clone(e.getOrigin().owner);
if (!isAccessible(env, origin, sym))
sym = new AccessError(env, origin, sym);
bestSoFar = selectBest(env, origin,
argtypes, typeargtypes,
sym, bestSoFar,
allowBoxing, useVarargs, false);
}
}
return bestSoFar;
}
/** Load toplevel or member class with given fully qualified name and
* verify that it is accessible.
* @param env The current environment.
* @param name The fully qualified name of the class to be loaded.
*/
Symbol loadClass(Env<AttrContext> env, Name name) {
try {
ClassSymbol c = reader.loadClass(name);
return isAccessible(env, c) ? c : new AccessError(c);
} catch (ClassReader.BadClassFile err) {
throw err;
} catch (CompletionFailure ex) {
return typeNotFound;
}
}
/** Find qualified member type.
* @param env The current environment.
* @param site The original type from where the selection takes
* place.
* @param name The type's name.
* @param c The class to search for the member type. This is
* always a superclass or implemented interface of
* site's class.
*/
Symbol findMemberType(Env<AttrContext> env,
Type site,
Name name,
TypeSymbol c) {
Symbol bestSoFar = typeNotFound;
Symbol sym;
Scope.Entry e = c.members().lookup(name);
while (e.scope != null) {
if (e.sym.kind == TYP) {
return isAccessible(env, site, e.sym)
? e.sym
: new AccessError(env, site, e.sym);
}
e = e.next();
}
Type st = types.supertype(c.type);
if (st != null && st.tag == CLASS) {
sym = findMemberType(env, site, name, st.tsym);
if (sym.kind < bestSoFar.kind) bestSoFar = sym;
}
for (List<Type> l = types.interfaces(c.type);
bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
l = l.tail) {
sym = findMemberType(env, site, name, l.head.tsym);
if (bestSoFar.kind < AMBIGUOUS && sym.kind < AMBIGUOUS &&
sym.owner != bestSoFar.owner)
bestSoFar = new AmbiguityError(bestSoFar, sym);
else if (sym.kind < bestSoFar.kind)
bestSoFar = sym;
}
return bestSoFar;
}
/** Find a global type in given scope and load corresponding class.
* @param env The current environment.
* @param scope The scope in which to look for the type.
* @param name The type's name.
*/
Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name) {
Symbol bestSoFar = typeNotFound;
for (Scope.Entry e = scope.lookup(name); e.scope != null; e = e.next()) {
Symbol sym = loadClass(env, e.sym.flatName());
if (bestSoFar.kind == TYP && sym.kind == TYP &&
bestSoFar != sym)
return new AmbiguityError(bestSoFar, sym);
else if (sym.kind < bestSoFar.kind)
bestSoFar = sym;
}
return bestSoFar;
}
/** Find an unqualified type symbol.
* @param env The current environment.
* @param name The type's name.
*/
Symbol findType(Env<AttrContext> env, Name name) {
Symbol bestSoFar = typeNotFound;
Symbol sym;
boolean staticOnly = false;
for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
if (isStatic(env1)) staticOnly = true;
for (Scope.Entry e = env1.info.scope.lookup(name);
e.scope != null;
e = e.next()) {
if (e.sym.kind == TYP) {
if (staticOnly &&
e.sym.type.tag == TYPEVAR &&
e.sym.owner.kind == TYP) return new StaticError(e.sym);
return e.sym;
}
}
sym = findMemberType(env1, env1.enclClass.sym.type, name,
env1.enclClass.sym);
if (staticOnly && sym.kind == TYP &&
sym.type.tag == CLASS &&
sym.type.getEnclosingType().tag == CLASS &&
env1.enclClass.sym.type.isParameterized() &&
sym.type.getEnclosingType().isParameterized())
return new StaticError(sym);
else if (sym.exists()) return sym;
else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
if ((encl.sym.flags() & STATIC) != 0)
staticOnly = true;
}
if (env.tree.getTag() != JCTree.IMPORT) {
sym = findGlobalType(env, env.toplevel.namedImportScope, name);
if (sym.exists()) return sym;
else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
sym = findGlobalType(env, env.toplevel.packge.members(), name);
if (sym.exists()) return sym;
else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
sym = findGlobalType(env, env.toplevel.starImportScope, name);
if (sym.exists()) return sym;
else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
}
return bestSoFar;
}
/** Find an unqualified identifier which matches a specified kind set.
* @param env The current environment.
* @param name The indentifier's name.
* @param kind Indicates the possible symbol kinds
* (a subset of VAL, TYP, PCK).
*/
Symbol findIdent(Env<AttrContext> env, Name name, int kind) {
Symbol bestSoFar = typeNotFound;
Symbol sym;
if ((kind & VAR) != 0) {
sym = findVar(env, name);
if (sym.exists()) return sym;
else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
}
if ((kind & TYP) != 0) {
sym = findType(env, name);
if (sym.exists()) return sym;
else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
}
if ((kind & PCK) != 0) return reader.enterPackage(name);
else return bestSoFar;
}
/** Find an identifier in a package which matches a specified kind set.
* @param env The current environment.
* @param name The identifier's name.
* @param kind Indicates the possible symbol kinds
* (a nonempty subset of TYP, PCK).
*/
Symbol findIdentInPackage(Env<AttrContext> env, TypeSymbol pck,
Name name, int kind) {
Name fullname = TypeSymbol.formFullName(name, pck);
Symbol bestSoFar = typeNotFound;
PackageSymbol pack = null;
if ((kind & PCK) != 0) {
pack = reader.enterPackage(fullname);
if (pack.exists()) return pack;
}
if ((kind & TYP) != 0) {
Symbol sym = loadClass(env, fullname);
if (sym.exists()) {
// don't allow programs to use flatnames
if (name == sym.name) return sym;
}
else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
}
return (pack != null) ? pack : bestSoFar;
}
/** Find an identifier among the members of a given type `site'.
* @param env The current environment.
* @param site The type containing the symbol to be found.
* @param name The identifier's name.
* @param kind Indicates the possible symbol kinds
* (a subset of VAL, TYP).
*/
Symbol findIdentInType(Env<AttrContext> env, Type site,
Name name, int kind) {
Symbol bestSoFar = typeNotFound;
Symbol sym;
if ((kind & VAR) != 0) {
sym = findField(env, site, name, site.tsym);
if (sym.exists()) return sym;
else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
}
if ((kind & TYP) != 0) {
sym = findMemberType(env, site, name, site.tsym);
if (sym.exists()) return sym;
else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
}
return bestSoFar;
}
/* ***************************************************************************
* Access checking
* The following methods convert ResolveErrors to ErrorSymbols, issuing
* an error message in the process
****************************************************************************/
/** If `sym' is a bad symbol: report error and return errSymbol
* else pass through unchanged,
* additional arguments duplicate what has been used in trying to find the
* symbol (--> flyweight pattern). This improves performance since we
* expect misses to happen frequently.
*
* @param sym The symbol that was found, or a ResolveError.
* @param pos The position to use for error reporting.
* @param site The original type from where the selection took place.
* @param name The symbol's name.
* @param argtypes The invocation's value arguments,
* if we looked for a method.
* @param typeargtypes The invocation's type arguments,
* if we looked for a method.
*/
Symbol access(Symbol sym,
DiagnosticPosition pos,
Symbol location,
Type site,
Name name,
boolean qualified,
List<Type> argtypes,
List<Type> typeargtypes) {
if (sym.kind >= AMBIGUOUS) {
ResolveError errSym = (ResolveError)sym;
if (!site.isErroneous() &&
!Type.isErroneous(argtypes) &&
(typeargtypes==null || !Type.isErroneous(typeargtypes)))
logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
}
return sym;
}
/** Same as original access(), but without location.
*/
Symbol access(Symbol sym,
DiagnosticPosition pos,
Type site,
Name name,
boolean qualified,
List<Type> argtypes,
List<Type> typeargtypes) {
return access(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
}
/** Same as original access(), but without type arguments and arguments.
*/
Symbol access(Symbol sym,
DiagnosticPosition pos,
Symbol location,
Type site,
Name name,
boolean qualified) {
if (sym.kind >= AMBIGUOUS)
return access(sym, pos, location, site, name, qualified, List.<Type>nil(), null);
else
return sym;
}
/** Same as original access(), but without location, type arguments and arguments.
*/
Symbol access(Symbol sym,
DiagnosticPosition pos,
Type site,
Name name,
boolean qualified) {
return access(sym, pos, site.tsym, site, name, qualified);
}
/** Check that sym is not an abstract method.
*/
void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
if ((sym.flags() & ABSTRACT) != 0)
log.error(pos, "abstract.cant.be.accessed.directly",
kindName(sym), sym, sym.location());
}
/* ***************************************************************************
* Debugging
****************************************************************************/
/** print all scopes starting with scope s and proceeding outwards.
* used for debugging.
*/
public void printscopes(Scope s) {
while (s != null) {
if (s.owner != null)
System.err.print(s.owner + ": ");
for (Scope.Entry e = s.elems; e != null; e = e.sibling) {
if ((e.sym.flags() & ABSTRACT) != 0)
System.err.print("abstract ");
System.err.print(e.sym + " ");
}
System.err.println();
s = s.next;
}
}
void printscopes(Env<AttrContext> env) {
while (env.outer != null) {
System.err.println("------------------------------");
printscopes(env.info.scope);
env = env.outer;
}
}
public void printscopes(Type t) {
while (t.tag == CLASS) {
printscopes(t.tsym.members());
t = types.supertype(t);
}
}
/* ***************************************************************************
* Name resolution
* Naming conventions are as for symbol lookup
* Unlike the find... methods these methods will report access errors
****************************************************************************/
/** Resolve an unqualified (non-method) identifier.
* @param pos The position to use for error reporting.
* @param env The environment current at the identifier use.
* @param name The identifier's name.
* @param kind The set of admissible symbol kinds for the identifier.
*/
Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
Name name, int kind) {
return access(
findIdent(env, name, kind),
pos, env.enclClass.sym.type, name, false);
}
/** Resolve an unqualified method identifier.
* @param pos The position to use for error reporting.
* @param env The environment current at the method invocation.
* @param name The identifier's name.
* @param argtypes The types of the invocation's value arguments.
* @param typeargtypes The types of the invocation's type arguments.
*/
Symbol resolveMethod(DiagnosticPosition pos,
Env<AttrContext> env,
Name name,
List<Type> argtypes,
List<Type> typeargtypes) {
Symbol sym = startResolution();
List<MethodResolutionPhase> steps = methodResolutionSteps;
while (steps.nonEmpty() &&
steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
sym.kind >= ERRONEOUS) {
currentStep = steps.head;
sym = findFun(env, name, argtypes, typeargtypes,
steps.head.isBoxingRequired,
env.info.varArgs = steps.head.isVarargsRequired);
methodResolutionCache.put(steps.head, sym);
steps = steps.tail;
}
if (sym.kind >= AMBIGUOUS) {//if nothing is found return the 'first' error
MethodResolutionPhase errPhase =
firstErroneousResolutionPhase();
sym = access(methodResolutionCache.get(errPhase),
pos, env.enclClass.sym.type, name, false, argtypes, typeargtypes);
env.info.varArgs = errPhase.isVarargsRequired;
}
return sym;
}
private Symbol startResolution() {
wrongMethod.clear();
wrongMethods.clear();
return methodNotFound;
}
/** Resolve a qualified method identifier
* @param pos The position to use for error reporting.
* @param env The environment current at the method invocation.
* @param site The type of the qualifying expression, in which
* identifier is searched.
* @param name The identifier's name.
* @param argtypes The types of the invocation's value arguments.
* @param typeargtypes The types of the invocation's type arguments.
*/
Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
Type site, Name name, List<Type> argtypes,
List<Type> typeargtypes) {
return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
}
Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
Symbol location, Type site, Name name, List<Type> argtypes,
List<Type> typeargtypes) {
Symbol sym = startResolution();
List<MethodResolutionPhase> steps = methodResolutionSteps;
while (steps.nonEmpty() &&
steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
sym.kind >= ERRONEOUS) {
currentStep = steps.head;
sym = findMethod(env, site, name, argtypes, typeargtypes,
steps.head.isBoxingRequired(),
env.info.varArgs = steps.head.isVarargsRequired(), false);
methodResolutionCache.put(steps.head, sym);
steps = steps.tail;
}
if (sym.kind >= AMBIGUOUS) {
if (site.tsym.isPolymorphicSignatureGeneric()) {
//polymorphic receiver - synthesize new method symbol
env.info.varArgs = false;
sym = findPolymorphicSignatureInstance(env,
site, name, null, argtypes);
}
else {
//if nothing is found return the 'first' error
MethodResolutionPhase errPhase =
firstErroneousResolutionPhase();
sym = access(methodResolutionCache.get(errPhase),
pos, location, site, name, true, argtypes, typeargtypes);
env.info.varArgs = errPhase.isVarargsRequired;
}
} else if (allowMethodHandles && sym.isPolymorphicSignatureGeneric()) {
//non-instantiated polymorphic signature - synthesize new method symbol
env.info.varArgs = false;
sym = findPolymorphicSignatureInstance(env,
site, name, (MethodSymbol)sym, argtypes);
}
return sym;
}
/** Find or create an implicit method of exactly the given type (after erasure).
* Searches in a side table, not the main scope of the site.
* This emulates the lookup process required by JSR 292 in JVM.
* @param env Attribution environment
* @param site The original type from where the selection takes place.
* @param name The method's name.
* @param spMethod A template for the implicit method, or null.
* @param argtypes The required argument types.
* @param typeargtypes The required type arguments.
*/
Symbol findPolymorphicSignatureInstance(Env<AttrContext> env, Type site,
Name name,
MethodSymbol spMethod, // sig. poly. method or null if none
List<Type> argtypes) {
Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
site, name, spMethod, argtypes);
long flags = ABSTRACT | HYPOTHETICAL | POLYMORPHIC_SIGNATURE |
(spMethod != null ?
spMethod.flags() & Flags.AccessFlags :
Flags.PUBLIC | Flags.STATIC);
Symbol m = null;
for (Scope.Entry e = polymorphicSignatureScope.lookup(name);
e.scope != null;
e = e.next()) {
Symbol sym = e.sym;
if (types.isSameType(mtype, sym.type) &&
(sym.flags() & Flags.STATIC) == (flags & Flags.STATIC) &&
types.isSameType(sym.owner.type, site)) {
m = sym;
break;
}
}
if (m == null) {
// create the desired method
m = new MethodSymbol(flags, name, mtype, site.tsym);
polymorphicSignatureScope.enter(m);
}
return m;
}
/** Resolve a qualified method identifier, throw a fatal error if not
* found.
* @param pos The position to use for error reporting.
* @param env The environment current at the method invocation.
* @param site The type of the qualifying expression, in which
* identifier is searched.
* @param name The identifier's name.
* @param argtypes The types of the invocation's value arguments.
* @param typeargtypes The types of the invocation's type arguments.
*/
public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
Type site, Name name,
List<Type> argtypes,
List<Type> typeargtypes) {
Symbol sym = resolveQualifiedMethod(
pos, env, site.tsym, site, name, argtypes, typeargtypes);
if (sym.kind == MTH) return (MethodSymbol)sym;
else throw new FatalError(
diags.fragment("fatal.err.cant.locate.meth",
name));
}
/** Resolve constructor.
* @param pos The position to use for error reporting.
* @param env The environment current at the constructor invocation.
* @param site The type of class for which a constructor is searched.
* @param argtypes The types of the constructor invocation's value
* arguments.
* @param typeargtypes The types of the constructor invocation's type
* arguments.
*/
Symbol resolveConstructor(DiagnosticPosition pos,
Env<AttrContext> env,
Type site,
List<Type> argtypes,
List<Type> typeargtypes) {
Symbol sym = startResolution();
List<MethodResolutionPhase> steps = methodResolutionSteps;
while (steps.nonEmpty() &&
steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
sym.kind >= ERRONEOUS) {
currentStep = steps.head;
sym = resolveConstructor(pos, env, site, argtypes, typeargtypes,
steps.head.isBoxingRequired(),
env.info.varArgs = steps.head.isVarargsRequired());
methodResolutionCache.put(steps.head, sym);
steps = steps.tail;
}
if (sym.kind >= AMBIGUOUS) {//if nothing is found return the 'first' error
MethodResolutionPhase errPhase = firstErroneousResolutionPhase();
sym = access(methodResolutionCache.get(errPhase),
pos, site, names.init, true, argtypes, typeargtypes);
env.info.varArgs = errPhase.isVarargsRequired();
}
return sym;
}
/** Resolve constructor using diamond inference.
* @param pos The position to use for error reporting.
* @param env The environment current at the constructor invocation.
* @param site The type of class for which a constructor is searched.
* The scope of this class has been touched in attribution.
* @param argtypes The types of the constructor invocation's value
* arguments.
* @param typeargtypes The types of the constructor invocation's type
* arguments.
*/
Symbol resolveDiamond(DiagnosticPosition pos,
Env<AttrContext> env,
Type site,
List<Type> argtypes,
List<Type> typeargtypes) {
Symbol sym = startResolution();
List<MethodResolutionPhase> steps = methodResolutionSteps;
while (steps.nonEmpty() &&
steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
sym.kind >= ERRONEOUS) {
currentStep = steps.head;
sym = resolveConstructor(pos, env, site, argtypes, typeargtypes,
steps.head.isBoxingRequired(),
env.info.varArgs = steps.head.isVarargsRequired());
methodResolutionCache.put(steps.head, sym);
steps = steps.tail;
}
if (sym.kind >= AMBIGUOUS) {
final JCDiagnostic details = sym.kind == WRONG_MTH ?
((InapplicableSymbolError)sym).explanation :
null;
Symbol errSym = new ResolveError(WRONG_MTH, "diamond error") {
@Override
JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
String key = details == null ?
"cant.apply.diamond" :
"cant.apply.diamond.1";
return diags.create(dkind, log.currentSource(), pos, key,
diags.fragment("diamond", site.tsym), details);
}
};
MethodResolutionPhase errPhase = firstErroneousResolutionPhase();
sym = access(errSym, pos, site, names.init, true, argtypes, typeargtypes);
env.info.varArgs = errPhase.isVarargsRequired();
}
return sym;
}
/** Resolve constructor.
* @param pos The position to use for error reporting.
* @param env The environment current at the constructor invocation.
* @param site The type of class for which a constructor is searched.
* @param argtypes The types of the constructor invocation's value
* arguments.
* @param typeargtypes The types of the constructor invocation's type
* arguments.
* @param allowBoxing Allow boxing and varargs conversions.
* @param useVarargs Box trailing arguments into an array for varargs.
*/
Symbol resolveConstructor(DiagnosticPosition pos, Env<AttrContext> env,
Type site, List<Type> argtypes,
List<Type> typeargtypes,
boolean allowBoxing,
boolean useVarargs) {
Symbol sym = findMethod(env, site,
names.init, argtypes,
typeargtypes, allowBoxing,
useVarargs, false);
chk.checkDeprecated(pos, env.info.scope.owner, sym);
return sym;
}
/** Resolve a constructor, throw a fatal error if not found.
* @param pos The position to use for error reporting.
* @param env The environment current at the method invocation.
* @param site The type to be constructed.
* @param argtypes The types of the invocation's value arguments.
* @param typeargtypes The types of the invocation's type arguments.
*/
public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
Type site,
List<Type> argtypes,
List<Type> typeargtypes) {
Symbol sym = resolveConstructor(
pos, env, site, argtypes, typeargtypes);
if (sym.kind == MTH) return (MethodSymbol)sym;
else throw new FatalError(
diags.fragment("fatal.err.cant.locate.ctor", site));
}
/** Resolve operator.
* @param pos The position to use for error reporting.
* @param optag The tag of the operation tree.
* @param env The environment current at the operation.
* @param argtypes The types of the operands.
*/
Symbol resolveOperator(DiagnosticPosition pos, int optag,
Env<AttrContext> env, List<Type> argtypes) {
Name name = treeinfo.operatorName(optag);
Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
null, false, false, true);
if (boxingEnabled && sym.kind >= WRONG_MTHS)
sym = findMethod(env, syms.predefClass.type, name, argtypes,
null, true, false, true);
return access(sym, pos, env.enclClass.sym.type, name,
false, argtypes, null);
}
/** Resolve operator.
* @param pos The position to use for error reporting.
* @param optag The tag of the operation tree.
* @param env The environment current at the operation.
* @param arg The type of the operand.
*/
Symbol resolveUnaryOperator(DiagnosticPosition pos, int optag, Env<AttrContext> env, Type arg) {
return resolveOperator(pos, optag, env, List.of(arg));
}
/** Resolve binary operator.
* @param pos The position to use for error reporting.
* @param optag The tag of the operation tree.
* @param env The environment current at the operation.
* @param left The types of the left operand.
* @param right The types of the right operand.
*/
Symbol resolveBinaryOperator(DiagnosticPosition pos,
int optag,
Env<AttrContext> env,
Type left,
Type right) {
return resolveOperator(pos, optag, env, List.of(left, right));
}
/**
* Resolve `c.name' where name == this or name == super.
* @param pos The position to use for error reporting.
* @param env The environment current at the expression.
* @param c The qualifier.
* @param name The identifier's name.
*/
Symbol resolveSelf(DiagnosticPosition pos,
Env<AttrContext> env,
TypeSymbol c,
Name name) {
Env<AttrContext> env1 = env;
boolean staticOnly = false;
while (env1.outer != null) {
if (isStatic(env1)) staticOnly = true;
if (env1.enclClass.sym == c) {
Symbol sym = env1.info.scope.lookup(name).sym;
if (sym != null) {
if (staticOnly) sym = new StaticError(sym);
return access(sym, pos, env.enclClass.sym.type,
name, true);
}
}
if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
env1 = env1.outer;
}
log.error(pos, "not.encl.class", c);
return syms.errSymbol;
}
/**
* Resolve `c.this' for an enclosing class c that contains the
* named member.
* @param pos The position to use for error reporting.
* @param env The environment current at the expression.
* @param member The member that must be contained in the result.
*/
Symbol resolveSelfContaining(DiagnosticPosition pos,
Env<AttrContext> env,
Symbol member,
boolean isSuperCall) {
Name name = names._this;
Env<AttrContext> env1 = isSuperCall ? env.outer : env;
boolean staticOnly = false;
if (env1 != null) {
while (env1 != null && env1.outer != null) {
if (isStatic(env1)) staticOnly = true;
if (env1.enclClass.sym.isSubClass(member.owner, types)) {
Symbol sym = env1.info.scope.lookup(name).sym;
if (sym != null) {
if (staticOnly) sym = new StaticError(sym);
return access(sym, pos, env.enclClass.sym.type,
name, true);
}
}
if ((env1.enclClass.sym.flags() & STATIC) != 0)
staticOnly = true;
env1 = env1.outer;
}
}
log.error(pos, "encl.class.required", member);
return syms.errSymbol;
}
/**
* Resolve an appropriate implicit this instance for t's container.
* JLS2 8.8.5.1 and 15.9.2
*/
Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
return resolveImplicitThis(pos, env, t, false);
}
Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) {
Type thisType = (((t.tsym.owner.kind & (MTH|VAR)) != 0)
? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
: resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type;
if (env.info.isSelfCall && thisType.tsym == env.enclClass.sym)
log.error(pos, "cant.ref.before.ctor.called", "this");
return thisType;
}
/* ***************************************************************************
* ResolveError classes, indicating error situations when accessing symbols
****************************************************************************/
public void logAccessError(Env<AttrContext> env, JCTree tree, Type type) {
AccessError error = new AccessError(env, type.getEnclosingType(), type.tsym);
logResolveError(error, tree.pos(), type.getEnclosingType().tsym, type.getEnclosingType(), null, null, null);
}
//where
private void logResolveError(ResolveError error,
DiagnosticPosition pos,
Symbol location,
Type site,
Name name,
List<Type> argtypes,
List<Type> typeargtypes) {
JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
pos, location, site, name, argtypes, typeargtypes);
if (d != null) {
d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
log.report(d);
}
}
private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
public Object methodArguments(List<Type> argtypes) {
return argtypes.isEmpty() ? noArgs : argtypes;
}
/**
* Root class for resolution errors. Subclass of ResolveError
* represent a different kinds of resolution error - as such they must
* specify how they map into concrete compiler diagnostics.
*/
private abstract class ResolveError extends Symbol {
/** The name of the kind of error, for debugging only. */
final String debugName;
ResolveError(int kind, String debugName) {
super(kind, 0, null, null, null);
this.debugName = debugName;
}
@Override
public <R, P> R accept(ElementVisitor<R, P> v, P p) {
throw new AssertionError();
}
@Override
public String toString() {
return debugName;
}
@Override
public boolean exists() {
return false;
}
/**
* Create an external representation for this erroneous symbol to be
* used during attribution - by default this returns the symbol of a
* brand new error type which stores the original type found
* during resolution.
*
* @param name the name used during resolution
* @param location the location from which the symbol is accessed
*/
protected Symbol access(Name name, TypeSymbol location) {
return types.createErrorType(name, location, syms.errSymbol.type).tsym;
}
/**
* Create a diagnostic representing this resolution error.
*
* @param dkind The kind of the diagnostic to be created (e.g error).
* @param pos The position to be used for error reporting.
* @param site The original type from where the selection took place.
* @param name The name of the symbol to be resolved.
* @param argtypes The invocation's value arguments,
* if we looked for a method.
* @param typeargtypes The invocation's type arguments,
* if we looked for a method.
*/
abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
DiagnosticPosition pos,
Symbol location,
Type site,
Name name,
List<Type> argtypes,
List<Type> typeargtypes);
/**
* A name designates an operator if it consists
* of a non-empty sequence of operator symbols +-~!/*%&|^<>=
*/
boolean isOperator(Name name) {
int i = 0;
while (i < name.getByteLength() &&
"+-~!*/%&|^<>=".indexOf(name.getByteAt(i)) >= 0) i++;
return i > 0 && i == name.getByteLength();
}
}
/**
* This class is the root class of all resolution errors caused by
* an invalid symbol being found during resolution.
*/
abstract class InvalidSymbolError extends ResolveError {
/** The invalid symbol found during resolution */
Symbol sym;
InvalidSymbolError(int kind, Symbol sym, String debugName) {
super(kind, debugName);
this.sym = sym;
}
@Override
public boolean exists() {
return true;
}
@Override
public String toString() {
return super.toString() + " wrongSym=" + sym;
}
@Override
public Symbol access(Name name, TypeSymbol location) {
if (sym.kind >= AMBIGUOUS)
return ((ResolveError)sym).access(name, location);
else if ((sym.kind & ERRONEOUS) == 0 && (sym.kind & TYP) != 0)
return types.createErrorType(name, location, sym.type).tsym;
else
return sym;
}
}
/**
* InvalidSymbolError error class indicating that a symbol matching a
* given name does not exists in a given site.
*/
class SymbolNotFoundError extends ResolveError {
SymbolNotFoundError(int kind) {
super(kind, "symbol not found error");
}
@Override
JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
DiagnosticPosition pos,
Symbol location,
Type site,
Name name,
List<Type> argtypes,
List<Type> typeargtypes) {
argtypes = argtypes == null ? List.<Type>nil() : argtypes;
typeargtypes = typeargtypes == null ? List.<Type>nil() : typeargtypes;
if (name == names.error)
return null;
if (isOperator(name)) {
boolean isUnaryOp = argtypes.size() == 1;
String key = argtypes.size() == 1 ?
"operator.cant.be.applied" :
"operator.cant.be.applied.1";
Type first = argtypes.head;
Type second = !isUnaryOp ? argtypes.tail.head : null;
return diags.create(dkind, log.currentSource(), pos,
key, name, first, second);
}
boolean hasLocation = false;
if (location == null) {
location = site.tsym;
}
if (!location.name.isEmpty()) {
if (location.kind == PCK && !site.tsym.exists()) {
return diags.create(dkind, log.currentSource(), pos,
"doesnt.exist", location);
}
hasLocation = !location.name.equals(names._this) &&
!location.name.equals(names._super);
}
boolean isConstructor = kind == ABSENT_MTH &&
name == names.table.names.init;
KindName kindname = isConstructor ? KindName.CONSTRUCTOR : absentKind(kind);
Name idname = isConstructor ? site.tsym.name : name;
String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
if (hasLocation) {
return diags.create(dkind, log.currentSource(), pos,
errKey, kindname, idname, //symbol kindname, name
typeargtypes, argtypes, //type parameters and arguments (if any)
getLocationDiag(location, site)); //location kindname, type
}
else {
return diags.create(dkind, log.currentSource(), pos,
errKey, kindname, idname, //symbol kindname, name
typeargtypes, argtypes); //type parameters and arguments (if any)
}
}
//where
private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
String key = "cant.resolve";
String suffix = hasLocation ? ".location" : "";
switch (kindname) {
case METHOD:
case CONSTRUCTOR: {
suffix += ".args";
suffix += hasTypeArgs ? ".params" : "";
}
}
return key + suffix;
}
private JCDiagnostic getLocationDiag(Symbol location, Type site) {
if (location.kind == VAR) {
return diags.fragment("location.1",
kindName(location),
location,
location.type);
} else {
return diags.fragment("location",
typeKindName(site),
site,
null);
}
}
}
/**
* InvalidSymbolError error class indicating that a given symbol
* (either a method, a constructor or an operand) is not applicable
* given an actual arguments/type argument list.
*/
class InapplicableSymbolError extends InvalidSymbolError {
/** An auxiliary explanation set in case of instantiation errors. */
JCDiagnostic explanation;
InapplicableSymbolError(Symbol sym) {
super(WRONG_MTH, sym, "inapplicable symbol error");
}
/** Update sym and explanation and return this.
*/
InapplicableSymbolError setWrongSym(Symbol sym, JCDiagnostic explanation) {
this.sym = sym;
if (this.sym == sym && explanation != null)
this.explanation = explanation; //update the details
return this;
}
/** Update sym and return this.
*/
InapplicableSymbolError setWrongSym(Symbol sym) {
this.sym = sym;
return this;
}
@Override
public String toString() {
return super.toString() + " explanation=" + explanation;
}
@Override
JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
DiagnosticPosition pos,
Symbol location,
Type site,
Name name,
List<Type> argtypes,
List<Type> typeargtypes) {
if (name == names.error)
return null;
if (isOperator(name)) {
boolean isUnaryOp = argtypes.size() == 1;
String key = argtypes.size() == 1 ?
"operator.cant.be.applied" :
"operator.cant.be.applied.1";
Type first = argtypes.head;
Type second = !isUnaryOp ? argtypes.tail.head : null;
return diags.create(dkind, log.currentSource(), pos,
key, name, first, second);
}
else {
Symbol ws = sym.asMemberOf(site, types);
return diags.create(dkind, log.currentSource(), pos,
"cant.apply.symbol" + (explanation != null ? ".1" : ""),
kindName(ws),
ws.name == names.init ? ws.owner.name : ws.name,
methodArguments(ws.type.getParameterTypes()),
methodArguments(argtypes),
kindName(ws.owner),
ws.owner.type,
explanation);
}
}
void clear() {
explanation = null;
}
@Override
public Symbol access(Name name, TypeSymbol location) {
return types.createErrorType(name, location, syms.errSymbol.type).tsym;
}
}
/**
* ResolveError error class indicating that a set of symbols
* (either methods, constructors or operands) is not applicable
* given an actual arguments/type argument list.
*/
class InapplicableSymbolsError extends ResolveError {
private List<Candidate> candidates = List.nil();
InapplicableSymbolsError(Symbol sym) {
super(WRONG_MTHS, "inapplicable symbols");
}
@Override
JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
DiagnosticPosition pos,
Symbol location,
Type site,
Name name,
List<Type> argtypes,
List<Type> typeargtypes) {
if (candidates.nonEmpty()) {
JCDiagnostic err = diags.create(dkind,
log.currentSource(),
pos,
"cant.apply.symbols",
name == names.init ? KindName.CONSTRUCTOR : absentKind(kind),
getName(),
argtypes);
return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(site));
} else {
return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
location, site, name, argtypes, typeargtypes);
}
}
//where
List<JCDiagnostic> candidateDetails(Type site) {
List<JCDiagnostic> details = List.nil();
for (Candidate c : candidates)
details = details.prepend(c.getDiagnostic(site));
return details.reverse();
}
Symbol addCandidate(MethodResolutionPhase currentStep, Symbol sym, JCDiagnostic details) {
Candidate c = new Candidate(currentStep, sym, details);
if (c.isValid() && !candidates.contains(c))
candidates = candidates.append(c);
return this;
}
void clear() {
candidates = List.nil();
}
private Name getName() {
Symbol sym = candidates.head.sym;
return sym.name == names.init ?
sym.owner.name :
sym.name;
}
private class Candidate {
final MethodResolutionPhase step;
final Symbol sym;
final JCDiagnostic details;
private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details) {
this.step = step;
this.sym = sym;
this.details = details;
}
JCDiagnostic getDiagnostic(Type site) {
return diags.fragment("inapplicable.method",
Kinds.kindName(sym),
sym.location(site, types),
sym.asMemberOf(site, types),
details);
}
@Override
public boolean equals(Object o) {
if (o instanceof Candidate) {
Symbol s1 = this.sym;
Symbol s2 = ((Candidate)o).sym;
if ((s1 != s2 &&
(s1.overrides(s2, s1.owner.type.tsym, types, false) ||
(s2.overrides(s1, s2.owner.type.tsym, types, false)))) ||
((s1.isConstructor() || s2.isConstructor()) && s1.owner != s2.owner))
return true;
}
return false;
}
boolean isValid() {
return (((sym.flags() & VARARGS) != 0 && step == VARARITY) ||
(sym.flags() & VARARGS) == 0 && step == (boxingEnabled ? BOX : BASIC));
}
}
}
/**
* An InvalidSymbolError error class indicating that a symbol is not
* accessible from a given site
*/
class AccessError extends InvalidSymbolError {
private Env<AttrContext> env;
private Type site;
AccessError(Symbol sym) {
this(null, null, sym);
}
AccessError(Env<AttrContext> env, Type site, Symbol sym) {
super(HIDDEN, sym, "access error");
this.env = env;
this.site = site;
if (debugResolve)
log.error("proc.messager", sym + " @ " + site + " is inaccessible.");
}
@Override
public boolean exists() {
return false;
}
@Override
JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
DiagnosticPosition pos,
Symbol location,
Type site,
Name name,
List<Type> argtypes,
List<Type> typeargtypes) {
if (sym.owner.type.tag == ERROR)
return null;
if (sym.name == names.init && sym.owner != site.tsym) {
return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
pos, location, site, name, argtypes, typeargtypes);
}
else if ((sym.flags() & PUBLIC) != 0
|| (env != null && this.site != null
&& !isAccessible(env, this.site))) {
return diags.create(dkind, log.currentSource(),
pos, "not.def.access.class.intf.cant.access",
sym, sym.location());
}
else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
return diags.create(dkind, log.currentSource(),
pos, "report.access", sym,
asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
sym.location());
}
else {
return diags.create(dkind, log.currentSource(),
pos, "not.def.public.cant.access", sym, sym.location());
}
}
}
/**
* InvalidSymbolError error class indicating that an instance member
* has erroneously been accessed from a static context.
*/
class StaticError extends InvalidSymbolError {
StaticError(Symbol sym) {
super(STATICERR, sym, "static error");
}
@Override
JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
DiagnosticPosition pos,
Symbol location,
Type site,
Name name,
List<Type> argtypes,
List<Type> typeargtypes) {
Symbol errSym = ((sym.kind == TYP && sym.type.tag == CLASS)
? types.erasure(sym.type).tsym
: sym);
return diags.create(dkind, log.currentSource(), pos,
"non-static.cant.be.ref", kindName(sym), errSym);
}
}
/**
* InvalidSymbolError error class indicating that a pair of symbols
* (either methods, constructors or operands) are ambiguous
* given an actual arguments/type argument list.
*/
class AmbiguityError extends InvalidSymbolError {
/** The other maximally specific symbol */
Symbol sym2;
AmbiguityError(Symbol sym1, Symbol sym2) {
super(AMBIGUOUS, sym1, "ambiguity error");
this.sym2 = sym2;
}
@Override
JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
DiagnosticPosition pos,
Symbol location,
Type site,
Name name,
List<Type> argtypes,
List<Type> typeargtypes) {
AmbiguityError pair = this;
while (true) {
if (pair.sym.kind == AMBIGUOUS)
pair = (AmbiguityError)pair.sym;
else if (pair.sym2.kind == AMBIGUOUS)
pair = (AmbiguityError)pair.sym2;
else break;
}
Name sname = pair.sym.name;
if (sname == names.init) sname = pair.sym.owner.name;
return diags.create(dkind, log.currentSource(),
pos, "ref.ambiguous", sname,
kindName(pair.sym),
pair.sym,
pair.sym.location(site, types),
kindName(pair.sym2),
pair.sym2,
pair.sym2.location(site, types));
}
}
enum MethodResolutionPhase {
BASIC(false, false),
BOX(true, false),
VARARITY(true, true);
boolean isBoxingRequired;
boolean isVarargsRequired;
MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
this.isBoxingRequired = isBoxingRequired;
this.isVarargsRequired = isVarargsRequired;
}
public boolean isBoxingRequired() {
return isBoxingRequired;
}
public boolean isVarargsRequired() {
return isVarargsRequired;
}
public boolean isApplicable(boolean boxingEnabled, boolean varargsEnabled) {
return (varargsEnabled || !isVarargsRequired) &&
(boxingEnabled || !isBoxingRequired);
}
}
private Map<MethodResolutionPhase, Symbol> methodResolutionCache =
new HashMap<MethodResolutionPhase, Symbol>(MethodResolutionPhase.values().length);
final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
private MethodResolutionPhase currentStep = null;
private MethodResolutionPhase firstErroneousResolutionPhase() {
MethodResolutionPhase bestSoFar = BASIC;
Symbol sym = methodNotFound;
List<MethodResolutionPhase> steps = methodResolutionSteps;
while (steps.nonEmpty() &&
steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
sym.kind >= WRONG_MTHS) {
sym = methodResolutionCache.get(steps.head);
bestSoFar = steps.head;
steps = steps.tail;
}
return bestSoFar;
}
}