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.comment;
  
  import java.util.List;
  import java.util.Map.Entry;
  import java.util.SortedMap;
  import java.util.TreeMap;
  
  import com.alibaba.p3c.pmd.I18nResources;
  import com.alibaba.p3c.pmd.lang.java.rule.util.NodeSortUtils;
  
  import net.sourceforge.pmd.lang.ast.Node;
  import net.sourceforge.pmd.lang.java.ast.ASTCompilationUnit;
  import net.sourceforge.pmd.lang.java.ast.ASTEnumConstant;
  import net.sourceforge.pmd.lang.java.ast.ASTExpression;
  import net.sourceforge.pmd.lang.java.ast.ASTFieldDeclaration;
  import net.sourceforge.pmd.lang.java.ast.AbstractJavaNode;
  import net.sourceforge.pmd.lang.java.ast.Comment;
  
  /**
   * [Mandatory] Single line comments in a method should be put above the code to be commented, by using // and
   * multiple lines by using \/* *\/. Alignment for comments should be noticed carefully.
   *
   * @author keriezhang
   * @date 2016/12/14
   */
  public class AvoidCommentBehindStatementRule extends AbstractAliCommentRule {
  
      @Override
      public Object visit(ASTCompilationUnit cUnit, Object data) {
          SortedMap<Integer, Node> itemsByLineNumber = orderedCommentsAndExpressions(cUnit);
          AbstractJavaNode lastNode = null;
  
          for (Entry<Integer, Node> entry : itemsByLineNumber.entrySet()) {
              Node value = entry.getValue();
              if (value instanceof AbstractJavaNode) {
                  lastNode = (AbstractJavaNode)value;
              } else if (value instanceof Comment) {
                  Comment comment = (Comment)value;
                  if (lastNode != null && (comment.getBeginLine() == lastNode.getBeginLine())
                      && (comment.getEndColumn() > lastNode.getBeginColumn())) {
                      addViolationWithMessage(data, lastNode,
                          I18nResources.getMessage("java.comment.AvoidCommentBehindStatementRule.violation.msg"),
                          comment.getBeginLine(), comment.getEndLine());
                  }
              }
          }
  
          return super.visit(cUnit, data);
      }
  
      /**
       * Check comments behind nodes.
       *
       * @param cUnit compilation unit
       * @return sorted comments and expressions
       */
      protected SortedMap<Integer, Node> orderedCommentsAndExpressions(ASTCompilationUnit cUnit) {
  
          SortedMap<Integer, Node> itemsByLineNumber = new TreeMap<>();
  
          // expression nodes
          List<ASTExpression> expressionNodes = cUnit.findDescendantsOfType(ASTExpression.class);
          NodeSortUtils.addNodesToSortedMap(itemsByLineNumber, expressionNodes);
  
          // filed declaration nodes
          List<ASTFieldDeclaration> fieldNodes =
              cUnit.findDescendantsOfType(ASTFieldDeclaration.class);
          NodeSortUtils.addNodesToSortedMap(itemsByLineNumber, fieldNodes);
  
          // enum constant nodes
          List<ASTEnumConstant> enumConstantNodes =
              cUnit.findDescendantsOfType(ASTEnumConstant.class);
          NodeSortUtils.addNodesToSortedMap(itemsByLineNumber, enumConstantNodes);
  
          NodeSortUtils.addNodesToSortedMap(itemsByLineNumber, cUnit.getComments());
  
          return itemsByLineNumber;
      }
  
  }
  