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.other;
  
  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.AbstractAliRule;
  import com.alibaba.p3c.pmd.lang.java.rule.util.NodeSortUtils;
  import com.alibaba.p3c.pmd.lang.java.util.ViolationUtils;
  
  import net.sourceforge.pmd.lang.ast.Node;
  import net.sourceforge.pmd.lang.java.ast.ASTAnnotation;
  import net.sourceforge.pmd.lang.java.ast.ASTClassOrInterfaceBodyDeclaration;
  import net.sourceforge.pmd.lang.java.ast.ASTCompilationUnit;
  import net.sourceforge.pmd.lang.java.ast.ASTExpression;
  import net.sourceforge.pmd.lang.java.ast.ASTMethodDeclaration;
  import net.sourceforge.pmd.lang.java.ast.AbstractJavaNode;
  import net.sourceforge.pmd.lang.java.ast.Comment;
  import net.sourceforge.pmd.lang.java.ast.FormalComment;
  import net.sourceforge.pmd.lang.java.ast.MultiLineComment;
  import net.sourceforge.pmd.lang.java.ast.SingleLineComment;
  import net.sourceforge.pmd.lang.java.ast.Token;
  
  /**
   * [Recommended] The total number of lines for a method should not be more than 80.
   * Note: The total number of lines, including the method signature, closing brace, codes, blank lines,
   * line breaks and any invisible lines, should not be more than 80 (comments are not included).
   *
   * @author keriezhang
   * @date 2018/1/9
   */
  public class MethodTooLongRule extends AbstractAliRule {
  
      private static final int MAX_LINE_COUNT = 80;
      private static final String ANNOTATION_PREFIX = "@";
  
      /**
       * sortedMap will be reinitialized for each source file.
       */
      private SortedMap<Integer, Node> sortedNodeAndComment;
  
      @Override
      public Object visit(ASTCompilationUnit cUnit, Object data) {
          sortedNodeAndComment = orderedCommentsAndExpressions(cUnit);
          return super.visit(cUnit, data);
      }
  
      @Override
      public Object visit(ASTMethodDeclaration node, Object data) {
          // Include method modifiers.
          ASTClassOrInterfaceBodyDeclaration classOrInterfaceBodyDecl =
              (ASTClassOrInterfaceBodyDeclaration)node.jjtGetParent();
  
          int startLine = classOrInterfaceBodyDecl.getBeginLine();
          int endLine = classOrInterfaceBodyDecl.getEndLine();
  
          Node firstChild = classOrInterfaceBodyDecl.jjtGetChild(0);
          // Method has annotation
          if (firstChild instanceof ASTAnnotation) {
              Token firstToken = (Token)classOrInterfaceBodyDecl.jjtGetFirstToken();
              // If annotation is before modifier, exclude the annotation.
              if (ANNOTATION_PREFIX.equals(firstToken.image)) {
                  ASTAnnotation annotation = (ASTAnnotation)firstChild;
                  Token lastToken = (Token)annotation.jjtGetLastToken();
  
                  // First token after annotation. The same line or next line after annotation.
                  Token next = lastToken.next;
                  startLine = next.beginLine;
              }
          }
  
          // Get comment line count.
          int commentLineCount = getCommentLineCount(node);
  
          if (endLine - startLine - commentLineCount + 1 > MAX_LINE_COUNT) {
              ViolationUtils.addViolationWithPrecisePosition(this, node, data,
                  I18nResources.getMessage("java.other.MethodTooLongRule.violation.msg", node.getName()));
          }
          return data;
      }
  
      /**
       * Order comments and expressions.
       *
       * @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);
  
          NodeSortUtils.addNodesToSortedMap(itemsByLineNumber, cUnit.getComments());
  
          return itemsByLineNumber;
      }
  
      /**
       * Get number of comment lines
       *
       * @param methodDecl
       * @return
       */
      private int getCommentLineCount(ASTMethodDeclaration methodDecl) {
          int lineCount = 0;
          AbstractJavaNode lastNode = null;
  
          for (Entry<Integer, Node> entry : sortedNodeAndComment.entrySet()) {
              Node value = entry.getValue();
              if (value.getBeginLine() <= methodDecl.getBeginLine()) {
                  continue;
              }
              if (value.getBeginLine() > methodDecl.getEndLine()) {
                  break;
              }
  
              // value should be either expression or comment.
              if (value instanceof AbstractJavaNode) {
                  lastNode = (AbstractJavaNode)value;
              } else if (value instanceof FormalComment || value instanceof MultiLineComment) {
                  Comment comment = (Comment)value;
                  lineCount += comment.getEndLine() - comment.getBeginLine() + 1;
              } else if (value instanceof SingleLineComment) {
                  SingleLineComment singleLineComment = (SingleLineComment)value;
                  // Comment may in the same line with node.
                  if (lastNode == null || singleLineComment.getBeginLine() != lastNode.getBeginLine()) {
                      lineCount += 1;
                  }
              }
          }
          return lineCount;
      }
  }
  