com.google.errorprone.bugpatterns.javadoc.ReturnFromVoid Maven / Gradle / Ivy
/*
* Copyright 2018 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.javadoc;
import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
import static com.google.errorprone.bugpatterns.javadoc.Utils.diagnosticPosition;
import static com.google.errorprone.util.ASTHelpers.getType;
import static com.google.errorprone.util.ASTHelpers.isSameType;
import com.google.errorprone.BugPattern;
import com.google.errorprone.BugPattern.StandardTags;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker;
import com.google.errorprone.bugpatterns.BugChecker.MethodTreeMatcher;
import com.google.errorprone.matchers.Description;
import com.sun.source.doctree.ReturnTree;
import com.sun.source.tree.MethodTree;
import com.sun.source.util.DocTreePath;
import com.sun.source.util.DocTreePathScanner;
/**
* Finds common Javadoc errors, and tries to suggest useful fixes.
*
* @author [email protected] (Graeme Morgan)
*/
@BugPattern(
summary = "Void methods should not have a @return tag.",
severity = WARNING,
tags = StandardTags.STYLE,
documentSuppression = false)
public final class ReturnFromVoid extends BugChecker implements MethodTreeMatcher {
@Override
public Description matchMethod(MethodTree methodTree, VisitorState state) {
DocTreePath path = Utils.getDocTreePath(state);
if (path != null) {
new VoidReturnTypeChecker(state, methodTree).scan(path, null);
}
return Description.NO_MATCH;
}
private final class VoidReturnTypeChecker extends DocTreePathScanner {
private final VisitorState state;
private final MethodTree methodTree;
private VoidReturnTypeChecker(VisitorState state, MethodTree methodTree) {
this.state = state;
this.methodTree = methodTree;
}
@Override
public Void visitReturn(ReturnTree returnTree, Void unused) {
if (isSameType(getType(methodTree.getReturnType()), state.getSymtab().voidType, state)) {
state.reportMatch(
describeMatch(
diagnosticPosition(getCurrentPath(), state), Utils.replace(returnTree, "", state)));
}
return super.visitReturn(returnTree, null);
}
}
}