com.alibaba.p3c.pmd.lang.java.rule.other.AvoidMissUseOfMathRandomRule Maven / Gradle / Ivy
/*
* Copyright 1999-2017 Alibaba Group.
*
* 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.alibaba.p3c.pmd.lang.java.rule.other;
import com.alibaba.p3c.pmd.lang.AbstractXpathRule;
import com.alibaba.p3c.pmd.lang.java.util.ViolationUtils;
import net.sourceforge.pmd.lang.ast.Node;
/**
* [Mandatory] The return type of Math.random() is double, value range is 0<=x<1 (0 is possible).
* If a random integer is required, do not multiply x by 10 then round the result.
* The correct way is to use nextInt or nextLong method which belong to Random Object.
*
* @author keriezhang
* @date 2017/04/14
*/
public class AvoidMissUseOfMathRandomRule extends AbstractXpathRule {
private static final String XPATH =
"//PrimaryExpression[./PrimaryPrefix/Name[@Image='Math.random'] and "
+ "../../MultiplicativeExpression/PrimaryExpression/PrimaryPrefix/Literal[matches(@Image, '^\\d+$')] and "
+ "../../../../../../CastExpression/Type/PrimitiveType[matches(@Image, '^(int|long)$')]"
+ "]";
public AvoidMissUseOfMathRandomRule() {
setXPath(XPATH);
}
@Override
public void addViolation(Object data, Node node, String arg) {
ViolationUtils.addViolationWithPrecisePosition(this, node, data);
}
}