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/*
* Copyright (c) 2014, 2015, 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 jdk.jshell;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Locale;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import javax.lang.model.element.Modifier;
import com.sun.source.tree.ArrayTypeTree;
import com.sun.source.tree.AssignmentTree;
import com.sun.source.tree.ClassTree;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.IdentifierTree;
import com.sun.source.tree.MethodTree;
import com.sun.source.tree.ModifiersTree;
import com.sun.source.tree.Tree;
import com.sun.source.tree.VariableTree;
import com.sun.tools.javac.tree.JCTree;
import com.sun.tools.javac.tree.Pretty;
import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;
import java.util.LinkedHashSet;
import java.util.Set;
import jdk.jshell.ClassTracker.ClassInfo;
import jdk.jshell.Key.ErroneousKey;
import jdk.jshell.Key.MethodKey;
import jdk.jshell.Key.TypeDeclKey;
import jdk.jshell.Snippet.SubKind;
import jdk.jshell.TaskFactory.AnalyzeTask;
import jdk.jshell.TaskFactory.BaseTask;
import jdk.jshell.TaskFactory.CompileTask;
import jdk.jshell.TaskFactory.ParseTask;
import jdk.jshell.TreeDissector.ExpressionInfo;
import jdk.jshell.Wrap.Range;
import jdk.jshell.Snippet.Status;
import static java.util.stream.Collectors.toList;
import static java.util.stream.Collectors.toSet;
import static jdk.internal.jshell.debug.InternalDebugControl.DBG_GEN;
import static jdk.jshell.Util.*;
import static jdk.internal.jshell.remote.RemoteCodes.DOIT_METHOD_NAME;
import static jdk.internal.jshell.remote.RemoteCodes.prefixPattern;
import static jdk.jshell.Snippet.SubKind.SINGLE_TYPE_IMPORT_SUBKIND;
import static jdk.jshell.Snippet.SubKind.SINGLE_STATIC_IMPORT_SUBKIND;
import static jdk.jshell.Snippet.SubKind.TYPE_IMPORT_ON_DEMAND_SUBKIND;
import static jdk.jshell.Snippet.SubKind.STATIC_IMPORT_ON_DEMAND_SUBKIND;
/**
* The Evaluation Engine. Source internal analysis, wrapping control,
* compilation, declaration. redefinition, replacement, and execution.
*
* @author Robert Field
*/
class Eval {
private static final Pattern IMPORT_PATTERN = Pattern.compile("import\\p{javaWhitespace}+(?<static>static\\p{javaWhitespace}+)?(?<fullname>[\\p{L}\\p{N}_\\$\\.]+\\.(?<name>[\\p{L}\\p{N}_\\$]+|\\*))");
private int varNumber = 0;
private final JShell state;
Eval(JShell state) {
this.state = state;
}
List<SnippetEvent> eval(String userSource) throws IllegalStateException {
String compileSource = Util.trimEnd(new MaskCommentsAndModifiers(userSource, false).cleared());
if (compileSource.length() == 0) {
return Collections.emptyList();
}
// String folding messes up position information.
ParseTask pt = state.taskFactory.new ParseTask(compileSource);
if (pt.getDiagnostics().hasOtherThanNotStatementErrors()) {
return compileFailResult(pt, userSource);
}
List<? extends Tree> units = pt.units();
if (units.isEmpty()) {
return compileFailResult(pt, userSource);
}
// Erase illegal modifiers
compileSource = new MaskCommentsAndModifiers(compileSource, true).cleared();
Tree unitTree = units.get(0);
state.debug(DBG_GEN, "Kind: %s -- %s\n", unitTree.getKind(), unitTree);
switch (unitTree.getKind()) {
case IMPORT:
return processImport(userSource, compileSource);
case VARIABLE:
return processVariables(userSource, units, compileSource, pt);
case EXPRESSION_STATEMENT:
return processExpression(userSource, compileSource);
case CLASS:
return processClass(userSource, unitTree, compileSource, SubKind.CLASS_SUBKIND, pt);
case ENUM:
return processClass(userSource, unitTree, compileSource, SubKind.ENUM_SUBKIND, pt);
case ANNOTATION_TYPE:
return processClass(userSource, unitTree, compileSource, SubKind.ANNOTATION_TYPE_SUBKIND, pt);
case INTERFACE:
return processClass(userSource, unitTree, compileSource, SubKind.INTERFACE_SUBKIND, pt);
case METHOD:
return processMethod(userSource, unitTree, compileSource, pt);
default:
return processStatement(userSource, compileSource);
}
}
private List<SnippetEvent> processImport(String userSource, String compileSource) {
Wrap guts = Wrap.importWrap(compileSource);
Matcher mat = IMPORT_PATTERN.matcher(compileSource);
String fullname;
String name;
boolean isStatic;
if (mat.find()) {
isStatic = mat.group("static") != null;
name = mat.group("name");
fullname = mat.group("fullname");
} else {
// bad import -- fake it
isStatic = compileSource.contains("static");
name = fullname = compileSource;
}
String fullkey = (isStatic ? "static-" : "") + fullname;
boolean isStar = name.equals("*");
String keyName = isStar
? fullname
: name;
SubKind snippetKind = isStar
? (isStatic ? STATIC_IMPORT_ON_DEMAND_SUBKIND : TYPE_IMPORT_ON_DEMAND_SUBKIND)
: (isStatic ? SINGLE_STATIC_IMPORT_SUBKIND : SINGLE_TYPE_IMPORT_SUBKIND);
Snippet snip = new ImportSnippet(state.keyMap.keyForImport(keyName, snippetKind),
userSource, guts, fullname, name, snippetKind, fullkey, isStatic, isStar);
return declare(snip);
}
private static class EvalPretty extends Pretty {
private final Writer out;
public EvalPretty(Writer writer, boolean bln) {
super(writer, bln);
this.out = writer;
}
/**
* Print string, DO NOT replacing all non-ascii character with unicode
* escapes.
*/
@Override
public void print(Object o) throws IOException {
out.write(o.toString());
}
static String prettyExpr(JCTree tree, boolean bln) {
StringWriter out = new StringWriter();
try {
new EvalPretty(out, bln).printExpr(tree);
} catch (IOException e) {
throw new AssertionError(e);
}
return out.toString();
}
}
private List<SnippetEvent> processVariables(String userSource, List<? extends Tree> units, String compileSource, ParseTask pt) {
List<SnippetEvent> allEvents = new ArrayList<>();
TreeDissector dis = TreeDissector.createByFirstClass(pt);
for (Tree unitTree : units) {
VariableTree vt = (VariableTree) unitTree;
String name = vt.getName().toString();
String typeName = EvalPretty.prettyExpr((JCTree) vt.getType(), false);
Tree baseType = vt.getType();
TreeDependencyScanner tds = new TreeDependencyScanner();
tds.scan(baseType); // Not dependent on initializer
StringBuilder sbBrackets = new StringBuilder();
while (baseType instanceof ArrayTypeTree) {
//TODO handle annotations too
baseType = ((ArrayTypeTree) baseType).getType();
sbBrackets.append("[]");
}
Range rtype = dis.treeToRange(baseType);
Range runit = dis.treeToRange(vt);
runit = new Range(runit.begin, runit.end - 1);
ExpressionTree it = vt.getInitializer();
Range rinit = null;
int nameMax = runit.end - 1;
SubKind subkind;
if (it != null) {
subkind = SubKind.VAR_DECLARATION_WITH_INITIALIZER_SUBKIND;
rinit = dis.treeToRange(it);
nameMax = rinit.begin - 1;
} else {
subkind = SubKind.VAR_DECLARATION_SUBKIND;
}
int nameStart = compileSource.lastIndexOf(name, nameMax);
if (nameStart < 0) {
throw new AssertionError("Name '" + name + "' not found");
}
int nameEnd = nameStart + name.length();
Range rname = new Range(nameStart, nameEnd);
Wrap guts = Wrap.varWrap(compileSource, rtype, sbBrackets.toString(), rname, rinit);
Snippet snip = new VarSnippet(state.keyMap.keyForVariable(name), userSource, guts,
name, subkind, typeName,
tds.declareReferences());
DiagList modDiag = modifierDiagnostics(vt.getModifiers(), dis, true);
List<SnippetEvent> res1 = declare(snip, modDiag);
allEvents.addAll(res1);
}
return allEvents;
}
private List<SnippetEvent> processExpression(String userSource, String compileSource) {
String name = null;
ExpressionInfo ei = typeOfExpression(compileSource);
ExpressionTree assignVar;
Wrap guts;
Snippet snip;
if (ei != null && ei.isNonVoid) {
String typeName = ei.typeName;
SubKind subkind;
if (ei.tree instanceof IdentifierTree) {
IdentifierTree id = (IdentifierTree) ei.tree;
name = id.getName().toString();
subkind = SubKind.VAR_VALUE_SUBKIND;
} else if (ei.tree instanceof AssignmentTree
&& (assignVar = ((AssignmentTree) ei.tree).getVariable()) instanceof IdentifierTree) {
name = assignVar.toString();
subkind = SubKind.ASSIGNMENT_SUBKIND;
} else {
subkind = SubKind.OTHER_EXPRESSION_SUBKIND;
}
if (shouldGenTempVar(subkind)) {
if (state.tempVariableNameGenerator != null) {
name = state.tempVariableNameGenerator.get();
}
while (name == null || state.keyMap.doesVariableNameExist(name)) {
name = "$" + ++varNumber;
}
guts = Wrap.tempVarWrap(compileSource, typeName, name);
Collection<String> declareReferences = null; //TODO
snip = new VarSnippet(state.keyMap.keyForVariable(name), userSource, guts,
name, SubKind.TEMP_VAR_EXPRESSION_SUBKIND, typeName, declareReferences);
} else {
guts = Wrap.methodReturnWrap(compileSource);
snip = new ExpressionSnippet(state.keyMap.keyForExpression(name, typeName), userSource, guts,
name, subkind);
}
} else {
guts = Wrap.methodWrap(compileSource);
if (ei == null) {
// We got no type info, check for not a statement by trying
AnalyzeTask at = trialCompile(guts);
if (at.getDiagnostics().hasNotStatement()) {
guts = Wrap.methodReturnWrap(compileSource);
at = trialCompile(guts);
}
if (at.hasErrors()) {
return compileFailResult(at, userSource);
}
}
snip = new StatementSnippet(state.keyMap.keyForStatement(), userSource, guts);
}
return declare(snip);
}
private List<SnippetEvent> processClass(String userSource, Tree unitTree, String compileSource, SubKind snippetKind, ParseTask pt) {
TreeDependencyScanner tds = new TreeDependencyScanner();
tds.scan(unitTree);
TreeDissector dis = TreeDissector.createByFirstClass(pt);
ClassTree klassTree = (ClassTree) unitTree;
String name = klassTree.getSimpleName().toString();
Wrap guts = Wrap.classMemberWrap(compileSource);
TypeDeclKey key = state.keyMap.keyForClass(name);
Wrap corralled = new Corraller(key.index(), compileSource, dis).corralType(klassTree, 1);
Snippet snip = new TypeDeclSnippet(state.keyMap.keyForClass(name), userSource, guts,
name, snippetKind,
corralled, tds.declareReferences(), tds.bodyReferences());
DiagList modDiag = modifierDiagnostics(klassTree.getModifiers(), dis, false);
return declare(snip, modDiag);
}
private List<SnippetEvent> processStatement(String userSource, String compileSource) {
Wrap guts = Wrap.methodWrap(compileSource);
// Check for unreachable by trying
AnalyzeTask at = trialCompile(guts);
if (at.hasErrors()) {
if (at.getDiagnostics().hasUnreachableError()) {
guts = Wrap.methodUnreachableSemiWrap(compileSource);
at = trialCompile(guts);
if (at.hasErrors()) {
if (at.getDiagnostics().hasUnreachableError()) {
// Without ending semicolon
guts = Wrap.methodUnreachableWrap(compileSource);
at = trialCompile(guts);
}
if (at.hasErrors()) {
return compileFailResult(at, userSource);
}
}
} else {
return compileFailResult(at, userSource);
}
}
Snippet snip = new StatementSnippet(state.keyMap.keyForStatement(), userSource, guts);
return declare(snip);
}
private OuterWrap wrapInClass(String className, Set<Key> except, String userSource, Wrap guts, Collection<Snippet> plus) {
String imports = state.maps.packageAndImportsExcept(except, plus);
return OuterWrap.wrapInClass(state.maps.packageName(), className, imports, userSource, guts);
}
OuterWrap wrapInClass(Snippet snip, Set<Key> except, Wrap guts, Collection<Snippet> plus) {
return wrapInClass(snip.className(), except, snip.source(), guts, plus);
}
private AnalyzeTask trialCompile(Wrap guts) {
OuterWrap outer = wrapInClass(REPL_DOESNOTMATTER_CLASS_NAME,
Collections.emptySet(), "", guts, null);
return state.taskFactory.new AnalyzeTask(outer);
}
private List<SnippetEvent> processMethod(String userSource, Tree unitTree, String compileSource, ParseTask pt) {
TreeDependencyScanner tds = new TreeDependencyScanner();
tds.scan(unitTree);
MethodTree mt = (MethodTree) unitTree;
TreeDissector dis = TreeDissector.createByFirstClass(pt);
DiagList modDiag = modifierDiagnostics(mt.getModifiers(), dis, true);
if (modDiag.hasErrors()) {
return compileFailResult(modDiag, userSource);
}
String unitName = mt.getName().toString();
Wrap guts = Wrap.classMemberWrap(compileSource);
Range typeRange = dis.treeToRange(mt.getReturnType());
String name = mt.getName().toString();
String parameterTypes
= mt.getParameters()
.stream()
.map(param -> dis.treeToRange(param.getType()).part(compileSource))
.collect(Collectors.joining(","));
String signature = "(" + parameterTypes + ")" + typeRange.part(compileSource);
MethodKey key = state.keyMap.keyForMethod(name, parameterTypes);
// rewrap with correct Key index
Wrap corralled = new Corraller(key.index(), compileSource, dis).corralMethod(mt);
Snippet snip = new MethodSnippet(key, userSource, guts,
unitName, signature,
corralled, tds.declareReferences(), tds.bodyReferences());
return declare(snip, modDiag);
}
/**
* The snippet has failed, return with the rejected event
*
* @param xt the task from which to extract the failure diagnostics
* @param userSource the incoming bad user source
* @return a rejected snippet event
*/
private List<SnippetEvent> compileFailResult(BaseTask xt, String userSource) {
return compileFailResult(xt.getDiagnostics(), userSource);
}
/**
* The snippet has failed, return with the rejected event
*
* @param diags the failure diagnostics
* @param userSource the incoming bad user source
* @return a rejected snippet event
*/
private List<SnippetEvent> compileFailResult(DiagList diags, String userSource) {
ErroneousKey key = state.keyMap.keyForErroneous();
Snippet snip = new ErroneousSnippet(key, userSource, null, SubKind.UNKNOWN_SUBKIND);
snip.setFailed(diags);
state.maps.installSnippet(snip);
return Collections.singletonList(new SnippetEvent(
snip, Status.NONEXISTENT, Status.REJECTED,
false, null, null, null)
);
}
private ExpressionInfo typeOfExpression(String expression) {
Wrap guts = Wrap.methodReturnWrap(expression);
TaskFactory.AnalyzeTask at = trialCompile(guts);
if (!at.hasErrors() && at.firstCuTree() != null) {
return TreeDissector.createByFirstClass(at)
.typeOfReturnStatement(at, state);
}
return null;
}
/**
* Should a temp var wrap the expression. TODO make this user configurable.
*
* @param snippetKind
* @return
*/
private boolean shouldGenTempVar(SubKind snippetKind) {
return snippetKind == SubKind.OTHER_EXPRESSION_SUBKIND;
}
List<SnippetEvent> drop(Snippet si) {
Unit c = new Unit(state, si);
Set<Unit> ins = c.dependents().collect(toSet());
Set<Unit> outs = compileAndLoad(ins);
return events(c, outs, null, null);
}
private List<SnippetEvent> declare(Snippet si) {
return declare(si, new DiagList());
}
private List<SnippetEvent> declare(Snippet si, DiagList generatedDiagnostics) {
Unit c = new Unit(state, si, null, generatedDiagnostics);
// Ignores duplicates
//TODO: remove, modify, or move to edit
if (c.isRedundant()) {
return Collections.emptyList();
}
Set<Unit> ins = new LinkedHashSet<>();
ins.add(c);
Set<Unit> outs = compileAndLoad(ins);
if (!si.status().isDefined
&& si.diagnostics().isEmpty()
&& si.unresolved().isEmpty()) {
// did not succeed, but no record of it, extract from others
si.setDiagnostics(outs.stream()
.flatMap(u -> u.snippet().diagnostics().stream())
.collect(Collectors.toCollection(DiagList::new)));
}
// If appropriate, execute the snippet
String value = null;
Exception exception = null;
if (si.isExecutable() && si.status().isDefined) {
try {
value = state.executionControl().commandInvoke(state.maps.classFullName(si));
value = si.subKind().hasValue()
? expunge(value)
: "";
} catch (EvalException ex) {
exception = translateExecutionException(ex);
} catch (UnresolvedReferenceException ex) {
exception = ex;
}
}
return events(c, outs, value, exception);
}
private List<SnippetEvent> events(Unit c, Collection<Unit> outs, String value, Exception exception) {
List<SnippetEvent> events = new ArrayList<>();
events.add(c.event(value, exception));
events.addAll(outs.stream()
.filter(u -> u != c)
.map(u -> u.event(null, null))
.collect(Collectors.toList()));
events.addAll(outs.stream()
.flatMap(u -> u.secondaryEvents().stream())
.collect(Collectors.toList()));
//System.err.printf("Events: %s\n", events);
return events;
}
private Set<Unit> compileAndLoad(Set<Unit> ins) {
if (ins.isEmpty()) {
return ins;
}
Set<Unit> replaced = new LinkedHashSet<>();
while (true) {
state.debug(DBG_GEN, "compileAndLoad %s\n", ins);
ins.stream().forEach(u -> u.initialize(ins));
AnalyzeTask at = state.taskFactory.new AnalyzeTask(ins);
ins.stream().forEach(u -> u.setDiagnostics(at));
// corral any Snippets that need it
AnalyzeTask cat;
if (ins.stream().anyMatch(u -> u.corralIfNeeded(ins))) {
// if any were corralled, re-analyze everything
cat = state.taskFactory.new AnalyzeTask(ins);
ins.stream().forEach(u -> u.setCorralledDiagnostics(cat));
} else {
cat = at;
}
ins.stream().forEach(u -> u.setStatus(cat));
// compile and load the legit snippets
boolean success;
while (true) {
List<Unit> legit = ins.stream()
.filter(u -> u.isDefined())
.collect(toList());
state.debug(DBG_GEN, "compileAndLoad ins = %s -- legit = %s\n",
ins, legit);
if (legit.isEmpty()) {
// no class files can be generated
success = true;
} else {
// re-wrap with legit imports
legit.stream().forEach(u -> u.setWrap(ins, legit));
// generate class files for those capable
CompileTask ct = state.taskFactory.new CompileTask(legit);
if (!ct.compile()) {
// oy! compile failed because of recursive new unresolved
if (legit.stream()
.filter(u -> u.smashingErrorDiagnostics(ct))
.count() > 0) {
// try again, with the erroreous removed
continue;
} else {
state.debug(DBG_GEN, "Should never happen error-less failure - %s\n",
legit);
}
}
// load all new classes
load(legit.stream()
.flatMap(u -> u.classesToLoad(ct.classInfoList(u)))
.collect(toList()));
// attempt to redefine the remaining classes
List<Unit> toReplace = legit.stream()
.filter(u -> !u.doRedefines())
.collect(toList());
// prevent alternating redefine/replace cyclic dependency
// loop by replacing all that have been replaced
if (!toReplace.isEmpty()) {
replaced.addAll(toReplace);
replaced.stream().forEach(u -> u.markForReplacement());
}
success = toReplace.isEmpty();
}
break;
}
// add any new dependencies to the working set
List<Unit> newDependencies = ins.stream()
.flatMap(u -> u.effectedDependents())
.collect(toList());
state.debug(DBG_GEN, "compileAndLoad %s -- deps: %s success: %s\n",
ins, newDependencies, success);
if (!ins.addAll(newDependencies) && success) {
// all classes that could not be directly loaded (because they
// are new) have been redefined, and no new dependnencies were
// identified
ins.stream().forEach(u -> u.finish());
return ins;
}
}
}
private void load(List<ClassInfo> cil) {
if (!cil.isEmpty()) {
state.executionControl().commandLoad(cil);
}
}
private EvalException translateExecutionException(EvalException ex) {
StackTraceElement[] raw = ex.getStackTrace();
int last = raw.length;
do {
if (last == 0) {
last = raw.length - 1;
break;
}
} while (!isWrap(raw[--last]));
StackTraceElement[] elems = new StackTraceElement[last + 1];
for (int i = 0; i <= last; ++i) {
StackTraceElement r = raw[i];
String rawKlass = r.getClassName();
Matcher matcher = prefixPattern.matcher(rawKlass);
String num;
if (matcher.find() && (num = matcher.group("num")) != null) {
int end = matcher.end();
if (rawKlass.charAt(end - 1) == '$') {
--end;
}
int id = Integer.parseInt(num);
Snippet si = state.maps.getSnippet(id);
String klass = expunge(rawKlass);
String method = r.getMethodName().equals(DOIT_METHOD_NAME) ? "" : r.getMethodName();
String file = "#" + id;
int line = si.outerWrap().wrapLineToSnippetLine(r.getLineNumber() - 1) + 1;
elems[i] = new StackTraceElement(klass, method, file, line);
} else if (r.getFileName().equals("<none>")) {
elems[i] = new StackTraceElement(r.getClassName(), r.getMethodName(), null, r.getLineNumber());
} else {
elems[i] = r;
}
}
String msg = ex.getMessage();
if (msg.equals("<none>")) {
msg = null;
}
return new EvalException(msg, ex.getExceptionClassName(), elems);
}
private boolean isWrap(StackTraceElement ste) {
return prefixPattern.matcher(ste.getClassName()).find();
}
private DiagList modifierDiagnostics(ModifiersTree modtree,
final TreeDissector dis, boolean isAbstractProhibited) {
class ModifierDiagnostic extends Diag {
final boolean fatal;
final String message;
ModifierDiagnostic(List<Modifier> list, boolean fatal) {
this.fatal = fatal;
StringBuilder sb = new StringBuilder();
sb.append((list.size() > 1) ? "Modifiers " : "Modifier ");
for (Modifier mod : list) {
sb.append("'");
sb.append(mod.toString());
sb.append("' ");
}
sb.append("not permitted in top-level declarations");
if (!fatal) {
sb.append(", ignored");
}
this.message = sb.toString();
}
@Override
public boolean isError() {
return fatal;
}
@Override
public long getPosition() {
return dis.getStartPosition(modtree);
}
@Override
public long getStartPosition() {
return dis.getStartPosition(modtree);
}
@Override
public long getEndPosition() {
return dis.getEndPosition(modtree);
}
@Override
public String getCode() {
return fatal
? "jdk.eval.error.illegal.modifiers"
: "jdk.eval.warn.illegal.modifiers";
}
@Override
public String getMessage(Locale locale) {
return message;
}
@Override
Unit unitOrNull() {
return null;
}
}
List<Modifier> list = new ArrayList<>();
boolean fatal = false;
for (Modifier mod : modtree.getFlags()) {
switch (mod) {
case SYNCHRONIZED:
case NATIVE:
list.add(mod);
fatal = true;
break;
case ABSTRACT:
if (isAbstractProhibited) {
list.add(mod);
fatal = true;
}
break;
case PUBLIC:
case PROTECTED:
case PRIVATE:
case STATIC:
case FINAL:
list.add(mod);
break;
}
}
return list.isEmpty()
? new DiagList()
: new DiagList(new ModifierDiagnostic(list, fatal));
}
}