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.constant;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import com.alibaba.p3c.pmd.lang.java.rule.AbstractAliRule;
  import com.alibaba.p3c.pmd.lang.java.util.namelist.NameListConfig;
  
  import net.sourceforge.pmd.lang.ast.Node;
  import net.sourceforge.pmd.lang.java.ast.ASTCompilationUnit;
  import net.sourceforge.pmd.lang.java.ast.ASTForStatement;
  import net.sourceforge.pmd.lang.java.ast.ASTIfStatement;
  import net.sourceforge.pmd.lang.java.ast.ASTLiteral;
  import net.sourceforge.pmd.lang.java.ast.ASTWhileStatement;
  import net.sourceforge.pmd.util.StringUtil;
  
  import org.apache.commons.lang3.StringUtils;
  import org.jaxen.JaxenException;
  
  /**
   * [Mandatory] Magic values, except for predefined, are forbidden in coding.
   *
   * @author shengfang.gsf
   * @date 2016/12/13
   */
  public class UndefineMagicConstantRule extends AbstractAliRule {
  
      /**
       * white list for undefined variable, may be added
       */
      private final static List<String> LITERAL_WHITE_LIST = NameListConfig.NAME_LIST_SERVICE.getNameList(
          UndefineMagicConstantRule.class.getSimpleName(), "LITERAL_WHITE_LIST");
  
      private final static String XPATH = "//Literal/../../../../..[not(VariableInitializer)]";
  
      /**
       * An undefined that belongs to non-looped if statements
       *
       * @param node compilation unit
       * @param data rule context
       */
      @Override
      public Object visit(ASTCompilationUnit node, Object data) {
          // removed repeat magic value , to prevent the parent class to find sub-variable nodes when there is a repeat
          List<ASTLiteral> currentLiterals = new ArrayList<ASTLiteral>();
          try {
              // Find the parent node of the undefined variable
              List<Node> parentNodes = node.findChildNodesWithXPath(XPATH);
  
              for (Node parentItem : parentNodes) {
                  List<ASTLiteral> literals = parentItem.findDescendantsOfType(ASTLiteral.class);
                  for (ASTLiteral literal : literals) {
                      if (inBlackList(literal) && !currentLiterals.contains(literal)) {
                          currentLiterals.add(literal);
                          String imageReplace = StringUtils.replace(literal.getImage(), "{", "'{");
                          addViolationWithMessage(data, literal,
                              "java.constant.UndefineMagicConstantRule.violation.msg", new Object[] {imageReplace});
                      }
                  }
              }
          } catch (JaxenException e) {
              e.printStackTrace();
          }
          return super.visit(node, data);
      }
  
      /**
       * Undefined variables are in the blacklist
       *
       * @param literal
       * @return
       */
      private boolean inBlackList(ASTLiteral literal) {
          String name = literal.getImage();
          int lineNum = literal.getBeginLine();
          // name is null,bool literal，belongs to white list
          if (name == null) {
              return false;
          }
          // filter white list
          for (String whiteItem : LITERAL_WHITE_LIST) {
              if (whiteItem.equals(name)) {
                  return false;
              }
          }
          ASTIfStatement ifStatement = literal.getFirstParentOfType(ASTIfStatement.class);
          if (ifStatement != null && lineNum == ifStatement.getBeginLine()) {
              ASTForStatement forStatement = ifStatement.getFirstParentOfType(ASTForStatement.class);
              ASTWhileStatement whileStatement = ifStatement.getFirstParentOfType(ASTWhileStatement.class);
              return forStatement == null && whileStatement == null;
          }
  
          // judge magic value belongs to  for statement 
          ASTForStatement blackForStatement = literal.getFirstParentOfType(ASTForStatement.class);
          if (blackForStatement != null && lineNum == blackForStatement.getBeginLine()) {
              return true;
          }
  
          // judge magic value belongs to while statement
          ASTWhileStatement blackWhileStatement = literal.getFirstParentOfType(ASTWhileStatement.class);
          return blackWhileStatement != null && lineNum == blackWhileStatement.getBeginLine();
      }
  }
  