com.google.errorprone.bugpatterns.IdentityHashMapUsage Maven / Gradle / Ivy
/*
* Copyright 2020 The Error Prone Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.errorprone.bugpatterns;
import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
import static com.google.errorprone.matchers.method.MethodMatchers.constructor;
import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker.AssignmentTreeMatcher;
import com.google.errorprone.bugpatterns.BugChecker.MethodInvocationTreeMatcher;
import com.google.errorprone.bugpatterns.BugChecker.NewClassTreeMatcher;
import com.google.errorprone.bugpatterns.BugChecker.VariableTreeMatcher;
import com.google.errorprone.fixes.SuggestedFix;
import com.google.errorprone.fixes.SuggestedFixes;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matcher;
import com.google.errorprone.suppliers.Supplier;
import com.google.errorprone.util.ASTHelpers;
import com.sun.source.tree.AssignmentTree;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.MethodInvocationTree;
import com.sun.source.tree.NewClassTree;
import com.sun.source.tree.VariableTree;
import com.sun.tools.javac.code.Type;
/** A {@link BugChecker}; see the associated {@link BugPattern} annotation for details. */
@BugPattern(
summary = "IdentityHashMap usage shouldn't be intermingled with Map",
severity = WARNING)
public class IdentityHashMapUsage extends BugChecker
implements MethodInvocationTreeMatcher,
AssignmentTreeMatcher,
VariableTreeMatcher,
NewClassTreeMatcher {
private static final String IDENTITY_HASH_MAP = "java.util.IdentityHashMap";
private static final Matcher IHM_ONE_ARG_METHODS =
instanceMethod().onExactClass(IDENTITY_HASH_MAP).namedAnyOf("equals", "putAll");
private static final Matcher IHM_CTOR_MAP_ARG =
constructor().forClass(IDENTITY_HASH_MAP).withParameters("java.util.Map");
@Override
public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
if (IHM_ONE_ARG_METHODS.matches(tree, state)
&& !ASTHelpers.isSameType(
ASTHelpers.getType(tree.getArguments().get(0)),
JAVA_UTIL_IDENTITYHASHMAP.get(state),
state)) {
return describeMatch(tree);
}
return Description.NO_MATCH;
}
@Override
public Description matchAssignment(AssignmentTree tree, VisitorState state) {
Type ihmType = JAVA_UTIL_IDENTITYHASHMAP.get(state);
if (!ASTHelpers.isSameType(ASTHelpers.getType(tree.getExpression()), ihmType, state)) {
return Description.NO_MATCH;
}
if (!ASTHelpers.isSameType(ASTHelpers.getType(tree.getVariable()), ihmType, state)) {
return describeMatch(tree);
}
return Description.NO_MATCH;
}
@Override
public Description matchVariable(VariableTree tree, VisitorState state) {
if (tree.getInitializer() == null) {
// method params don't have initializers.
return Description.NO_MATCH;
}
Type ihmType = JAVA_UTIL_IDENTITYHASHMAP.get(state);
if (ASTHelpers.isSameType(ASTHelpers.getType(tree.getType()), ihmType, state)) {
return Description.NO_MATCH;
}
Type type = ASTHelpers.getType(tree.getInitializer());
if (ASTHelpers.isSameType(type, ihmType, state)) {
SuggestedFix.Builder fix = SuggestedFix.builder();
fix.replace(tree.getType(), SuggestedFixes.qualifyType(state, fix, type));
return describeMatch(tree, fix.build());
}
return Description.NO_MATCH;
}
@Override
public Description matchNewClass(NewClassTree tree, VisitorState state) {
if (IHM_CTOR_MAP_ARG.matches(tree, state)
&& !ASTHelpers.isSameType(
ASTHelpers.getType(tree.getArguments().get(0)),
JAVA_UTIL_IDENTITYHASHMAP.get(state),
state)) {
return describeMatch(tree);
}
return Description.NO_MATCH;
}
private static final Supplier JAVA_UTIL_IDENTITYHASHMAP =
VisitorState.memoize(state -> state.getTypeFromString(IDENTITY_HASH_MAP));
}