com.google.errorprone.bugpatterns.ReachabilityFenceUsage Maven / Gradle / Ivy
/*
* Copyright 2017 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.Description.NO_MATCH;
import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker.MethodInvocationTreeMatcher;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matcher;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.MethodInvocationTree;
import com.sun.source.tree.Tree;
import com.sun.source.tree.TryTree;
/** A {@link BugChecker}; see the associated {@link BugPattern} annotation for details. */
@BugPattern(
name = "ReachabilityFenceUsage",
summary = "reachabilityFence should always be called inside a finally block",
severity = WARNING)
public class ReachabilityFenceUsage extends BugChecker implements MethodInvocationTreeMatcher {
private static final Matcher FENCE_MATCHER =
staticMethod().onClass("java.lang.ref.Reference").named("reachabilityFence");
@Override
public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
if (!FENCE_MATCHER.matches(tree, state)) {
return NO_MATCH;
}
Tree previous = null;
OUTER:
for (Tree enclosing : state.getPath().getParentPath()) {
switch (enclosing.getKind()) {
case TRY:
if (((TryTree) enclosing).getFinallyBlock().equals(previous)) {
return NO_MATCH;
}
break;
case CLASS:
case METHOD:
case LAMBDA_EXPRESSION:
break OUTER;
default: // fall out
}
previous = enclosing;
}
return describeMatch(tree);
}
}