/*
* Copyright 2012 Google Inc. All Rights Reserved.
*
* 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.Category.JDK;
import static com.google.errorprone.BugPattern.MaturityLevel.EXPERIMENTAL;
import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
import static com.google.errorprone.bugpatterns.BugChecker.MethodInvocationTreeMatcher;
import static com.google.errorprone.matchers.Matchers.instanceMethod;
import static com.google.errorprone.matchers.Matchers.methodSelect;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.fixes.SuggestedFix;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matchers;
import com.google.errorprone.util.ASTHelpers;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.MemberSelectTree;
import com.sun.source.tree.MethodInvocationTree;
import com.sun.tools.javac.code.Symbol.TypeSymbol;
import java.lang.annotation.Retention;
/**
* @author scottjohnson@google.com (Scott Johnson)
*/
@BugPattern(name = "NonRuntimeAnnotation",
summary = "Calling getAnnotation on an annotation that is not retained at runtime.",
explanation = "Calling getAnnotation on an annotation that does not have its Retention set to "
+ "RetentionPolicy.RUNTIME will always return null.",
category = JDK, severity = ERROR, maturity = EXPERIMENTAL)
public class NonRuntimeAnnotation extends BugChecker implements MethodInvocationTreeMatcher {
@Override
public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
if (!methodSelect(
instanceMethod(Matchers.<ExpressionTree>isSubtypeOf("java.lang.Class"), "getAnnotation"))
.matches(tree, state)) {
return Description.NO_MATCH;
}
MemberSelectTree memTree = (MemberSelectTree) tree.getArguments().get(0);
TypeSymbol annotation = ASTHelpers.getSymbol(memTree.getExpression()).type.tsym;
Retention retention = ASTHelpers.getAnnotation(annotation, Retention.class);
if (retention != null && retention.value().equals(RUNTIME)) {
return Description.NO_MATCH;
}
return describeMatch(tree, SuggestedFix.replace(tree, "null"));
}
}