/*
* Copyright 2013 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.inject;
import static com.google.errorprone.BugPattern.Category.INJECT;
import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
import static com.google.errorprone.matchers.ChildMultiMatcher.MatchType.AT_LEAST_ONE;
import static com.google.errorprone.matchers.InjectMatchers.IS_DAGGER_COMPONENT;
import static com.google.errorprone.matchers.InjectMatchers.IS_SCOPING_ANNOTATION;
import static com.google.errorprone.matchers.Matchers.annotations;
import com.google.common.base.Joiner;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker;
import com.google.errorprone.bugpatterns.BugChecker.ClassTreeMatcher;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.MultiMatcher;
import com.google.errorprone.matchers.MultiMatcher.MultiMatchResult;
import com.sun.source.tree.AnnotationTree;
import com.sun.source.tree.ClassTree;
import com.sun.source.tree.Tree;
import java.util.List;
/**
* This checker matches if a class has more than one annotation that is a scope annotation(that is,
* the annotation is either annotated with Guice's {@code @ScopeAnnotation} or Javax's
* {@code @Scope}).
*
* @author sgoldfeder@google.com (Steven Goldfeder)
*/
@BugPattern(
name = "InjectMoreThanOneScopeAnnotationOnClass",
altNames = "MoreThanOneScopeAnnotationOnClass",
summary = "A class can be annotated with at most one scope annotation.",
explanation =
"Annotating a class with more than one scope annotation is "
+ "invalid according to the JSR-330 specification. ",
category = INJECT,
severity = ERROR
)
public class MoreThanOneScopeAnnotationOnClass extends BugChecker implements ClassTreeMatcher {
private static final MultiMatcher<Tree, AnnotationTree> SCOPE_ANNOTATION_MATCHER =
annotations(AT_LEAST_ONE, IS_SCOPING_ANNOTATION);
@Override
public final Description matchClass(ClassTree classTree, VisitorState state) {
MultiMatchResult<AnnotationTree> scopeAnnotationResult =
SCOPE_ANNOTATION_MATCHER.multiMatchResult(classTree, state);
if (scopeAnnotationResult.matches() && !IS_DAGGER_COMPONENT.matches(classTree, state)) {
List<AnnotationTree> scopeAnnotations = scopeAnnotationResult.matchingNodes();
if (scopeAnnotations.size() > 1) {
return buildDescription(classTree)
.setMessage(
"This class is annotated with more than one scope annotation: "
+ annotationDebugString(scopeAnnotations)
+ ". However, classes can only have one scope annotation applied to them. "
+ "Please remove all but one of them.")
.build();
}
}
return Description.NO_MATCH;
}
private String annotationDebugString(List<AnnotationTree> scopeAnnotations) {
return Joiner.on(", ").join(scopeAnnotations);
}
}