content: /*
   * 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.flowcontrol;
  
  import com.alibaba.p3c.pmd.lang.java.rule.AbstractAliRule;
  
  import net.sourceforge.pmd.lang.java.ast.ASTBlock;
  import net.sourceforge.pmd.lang.java.ast.ASTForStatement;
  import net.sourceforge.pmd.lang.java.ast.ASTIfStatement;
  import net.sourceforge.pmd.lang.java.ast.ASTStatement;
  import net.sourceforge.pmd.lang.java.ast.ASTWhileStatement;
  
  /**
   * [Mandatory] Braces are used with if, else, for, do and while statements, even if the body contains only a single
   * statement. Avoid using the following example:
   * <pre>
   * if (condition) statements;
   * </pre>
   *
   * @author zenghou.fw
   * @date 2016/11/22
   */
  public class NeedBraceRule extends AbstractAliRule {
      private static final String STATEMENT_BLOCK = "Statement/Block";
  
      private static final String MESSAGE_KEY = "java.flowcontrol.NeedBraceRule.violation.msg";
  
      @Override
      public Object visit(ASTIfStatement node, Object data) {
          // SwitchStatement without {} fail by compilaton, no need to check here
          if (!node.hasDescendantMatchingXPath(STATEMENT_BLOCK)) {
              addViolationWithMessage(data, node, MESSAGE_KEY,
                  new Object[] {node.jjtGetFirstToken().toString()});
          }
          if (node.hasElse()) {
              // IfStatement with else have 2 expression blocks, should never throws NPE
              ASTStatement elseStms = node.findChildrenOfType(ASTStatement.class).get(1);
  
              if (!elseStms.hasDescendantOfAnyType(ASTBlock.class, ASTIfStatement.class)) {
                  addViolationWithMessage(data, elseStms, MESSAGE_KEY, new Object[] {"else"});
              }
          }
          return super.visit(node, data);
      }
  
      @Override
      public Object visit(ASTForStatement node, Object data) {
          if (!node.hasDescendantMatchingXPath(STATEMENT_BLOCK)) {
              addViolationWithMessage(data, node, MESSAGE_KEY, new Object[] {"for"});
          }
          return super.visit(node, data);
      }
  
      @Override
      public Object visit(ASTWhileStatement node, Object data) {
          if (!node.hasDescendantMatchingXPath(STATEMENT_BLOCK)) {
              addViolationWithMessage(data, node, MESSAGE_KEY, new Object[] {"while"});
          }
          return super.visit(node, data);
      }
  
  }
  