com.google.errorprone.bugpatterns.OverrideThrowableToString 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.common.collect.ImmutableList.toImmutableList;
import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
import com.google.common.collect.ImmutableList;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker.ClassTreeMatcher;
import com.google.errorprone.fixes.SuggestedFixes;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matchers;
import com.google.errorprone.util.ASTHelpers;
import com.sun.source.tree.ClassTree;
import com.sun.source.tree.MethodTree;
/**
* Warns against overriding toString() in a Throwable class and suggests getMessage()
*
* @author [email protected] (Maria Sam)
*/
@BugPattern(
name = "OverrideThrowableToString",
summary =
"To return a custom message with a Throwable class, one should "
+ "override getMessage() instead of toString().",
severity = WARNING)
public final class OverrideThrowableToString extends BugChecker implements ClassTreeMatcher {
@Override
public Description matchClass(ClassTree classTree, VisitorState state) {
if (!ASTHelpers.isSubtype(
ASTHelpers.getType(classTree), state.getSymtab().throwableType, state)) {
return Description.NO_MATCH;
}
ImmutableList methods =
classTree.getMembers().stream()
.filter(m -> m instanceof MethodTree)
.map(m -> (MethodTree) m)
.collect(toImmutableList());
if (methods.stream().anyMatch(m -> m.getName().contentEquals("getMessage"))) {
return Description.NO_MATCH;
}
return methods.stream()
.filter(m -> Matchers.toStringMethodDeclaration().matches(m, state))
.findFirst()
.map(m -> describeMatch(m, SuggestedFixes.renameMethod(m, "getMessage", state)))
.orElse(Description.NO_MATCH);
}
}