com.google.errorprone.bugpatterns.MathAbsoluteRandom 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;
import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
import static com.google.errorprone.matchers.Matchers.allOf;
import static com.google.errorprone.matchers.Matchers.argument;
import static com.google.errorprone.matchers.Matchers.instanceMethod;
import static com.google.errorprone.matchers.Matchers.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.MethodInvocationTree;
/**
* @author [email protected] (Kayla Walker)
*/
@BugPattern(
summary =
"Math.abs does not always give a positive result. Please consider other "
+ "methods for positive random numbers.",
severity = WARNING)
public class MathAbsoluteRandom extends BugChecker implements MethodInvocationTreeMatcher {
private static final Matcher RANDOM_ABS_VAL =
allOf(
staticMethod().onClass("java.lang.Math").named("abs"),
argument(
0,
instanceMethod()
.onDescendantOf("java.util.Random")
.namedAnyOf("nextInt", "nextLong")
.withNoParameters()));
@Override
public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
if (RANDOM_ABS_VAL.matches(tree, state)) {
return describeMatch(tree);
}
return Description.NO_MATCH;
}
}