com.xenoamess.p3c.pmd.lang.java.rule.flowcontrol.SwitchExpressionRule 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.xenoamess.p3c.pmd.lang.java.rule.flowcontrol;
import com.xenoamess.p3c.pmd.lang.java.rule.AbstractAliRule;
import net.sourceforge.pmd.lang.java.ast.ASTSwitchExpression;
/**
* [Mandatory] In a switch expression, each case should be finished by break/return.
* If not, a note should be included to describe at which case it will stop. Within every switch block,
* a default statement must be present, even if it is empty.
*
* @author XenoAmess
* @date 2020/4/22
*/
public class SwitchExpressionRule extends AbstractAliRule {
private static final String MESSAGE_KEY_PREFIX = "java.flowcontrol.SwitchExpressionRule.violation";
@Override
public Object visit(ASTSwitchExpression node, Object data) {
checkDefault(node, data);
return super.visit(node, data);
}
/**
* Check if switch statement contains default branch
*
* @param node node
* @param data ruleContext
*/
private void checkDefault(ASTSwitchExpression node, Object data) {
final String switchLabelCheckXpath = "SwitchLabel[@Default = 'true']";
final String switchLabeledExpressionCheckXpath = "SwitchLabeledExpression[SwitchLabel[@Default = 'true']]";
final String switchLabeledBlockCheckXpath = "SwitchLabeledBlock[SwitchLabel[@Default = 'true']]";
if (
!node.hasDescendantMatchingXPath(switchLabelCheckXpath)
&& !node.hasDescendantMatchingXPath(switchLabeledExpressionCheckXpath)
&& !node.hasDescendantMatchingXPath(switchLabeledBlockCheckXpath)
) {
addViolationWithMessage(data, node, MESSAGE_KEY_PREFIX + ".nodefault");
}
}
}