一键解析XML文件(利用Digester实现可配置)

 

      大部分程序员，平时工作中除了与Bug相伴之外，想必也会很多种多样的文件打交道吧。当然,XML 就是其中之一，获取交互数据,创建规则等等，都离不开他。XML是个非常强大的描述语言，相比而言,txt之流则功力较弱了些。

     XML那么重要，单解析XML的工作却繁杂无聊。原因如下：解析XML工具繁杂,每个人掌握的东西不一样;学习新工具又浪费时间;解析规则只是个体力活。

    程序员的辛苦，也就体现于此了。一般程序员总是抱怨忙啊忙，累啊累。我们作为程序员来说，更应该想一想想法设法吧东西提炼一下，减少重复的工作。 说这些题外话，是有原因的。我现在的大部分同事，加班加点在哪加班，貌似很辛苦，看一下他们的工作，让人很无奈。代码是一大段一大段的写，确实一晚上写个百十行，是非常“有成就感”的。

如生成XML 文件，用拼串的方式实现。一个小小的xml，往往都50多行。让人很无语。

   解析XML, 往往都需要有一套解析规则。而我们可以动态创建解析规则。让后根据规则将xml文件数据放到Map中。思路简单至极。其他扩展，暂时不考虑。

主要步骤 分为2部分

第一部分  使用Digester实现可配置的规则树结构

 

1)   规则节点对象

public     class Node{
   private String nodeName;
   private List children = new ArrayList();
   /**
    * 属性列表,以逗号分隔
    */
   private String attrs="";
    
   public String getAttrs() {
     return attrs;
  }
   public void setAttrs(String values) {
     this.attrs= values;
  }
   public String getNodeName() {
     return nodeName;
  }
   public void setNodeName(String nodeName) {
     this.nodeName = nodeName;
  }
   public List getChildren() {
     return children;
  }
   public void addChildren(Node node) {
     this.children.add(node);
  }
  @Override
   public String toString() {
    
     return this.nodeName+ ":"+ "have"+ this.getChildren().size()+ "子节点";
  }
}

 

(2) 定义xml 解析规则文件，当然也可以写编码实现。

 

<? xml version ="1.0" ?>
<!DOCTYPE digester-rules PUBLIC "-//Jakarta Apache //DTD digester-rules XML V1.0//EN" "http://jakarta.apache.org/commons/digester/dtds/digester-rules.dtd">
< digester-rules >
         < pattern value ="root" >
               < object-create-rule classname ="com.aisino.common.parse.Node" />
               < set-properties-rule />
               < set-next-rule methodname ="add" />
                
               < pattern value ="level1" >
                 < object-create-rule classname ="com.aisino.common.parse.Node" />
                 < set-properties-rule />
               < set-next-rule methodname ="addChildren" />
               < pattern value ="level2" >
                 < object-create-rule classname ="com.aisino.common.parse.Node" />
                 < set-properties-rule />
                <!--     
                <call-method-rule methodname="setNodeName" paramcount="1" paramtypes="java.lang.String"/>
                <call-param-rule paramnumber="0"/>
                 -->
                 < pattern value ="level3" >
                     < object-create-rule classname ="com.aisino.common.parse.Node" />
                     < set-properties-rule />
                         < set-next-rule methodname ="addChildren" />
                         < pattern value ="level4" >
                       < object-create-rule classname ="com.aisino.common.parse.Node" />
                       < set-properties-rule />
                         < set-next-rule methodname ="addChildren" />
                         < pattern value ="level5" >
                         < object-create-rule classname ="com.aisino.common.parse.Node" />
                         < set-properties-rule />
                             < set-next-rule methodname ="addChildren" />
                         </ pattern >
                         </ pattern >
                 </ pattern >
                    
                 < set-next-rule methodname ="addChildren" />
               </ pattern >
             </ pattern >
         </ pattern >
</ digester-rules >

 

3)  规则解析类RuleLoader

public class RuleLoader {
   private static final Log logger = LogFactory.getLog(RuleLoader. class);
   private URL digesterRulesURL;
   private URL fileURL;
   public RuleLoader(String rulePath,String filePath){
      digesterRulesURL= getURL(rulePath);
      fileURL = getURL(filePath);
//    digesterRulesURL= getClass().getClassLoader().getResource(rulePath);
  }
   public RuleLoader(URL digesterRulesURL,URL fileURL){
     this.digesterRulesURL = digesterRulesURL;
     this.fileURL = fileURL;
  }

   public static RuleLoader    getXmlRuleLoader(String filePath){
    URL url = getURL( "classpath:com/aisino/common/parse/xml-rules.xml");
     return new RuleLoader(url,getURL(filePath));
  }

   /**
    *    
    * 自定义指定规则<br/>
    * 需要对Digester 解析规则熟悉
    * @return
    */
   public List parseRules(){
     ClassLoader classLoader = getClass().getClassLoader();
     Object root = new ArrayList();
     try {
      DigesterLoader.load(digesterRulesURL, classLoader, fileURL,root);
    } catch (IOException e) {
      logger.error( "IOException");
    } catch (SAXException e) {
      logger.error( "SAX error");
    } catch (DigesterLoadingException e) {
      logger.error( "an error occurs while parsing XML into Digester rules");
    }
     return (List)root;
  }

   /**
    *    
    * 解析XML数据，并将数据保存至Map
    * 最多支持5级
    * XML节点:主要表示root、level1,level2,level3,level4,level5<br/>
    *  for example:<br/>
  *  <root nodeName="dataExchangePackage"><br/>
  *     <level1 nodeName="envelopeInfo"><br/>
  *        <level2 nodeName="sourceID" /><br/>
  *        <level2 nodeName="destinationID" /><br/>
  *        <level2 nodeName="destinationAppID" /><br/>
  *        <level2 nodeName="businessType" /><br/>
  *        <level2 nodeName="globalBusinessID" /><br/>
  *     </level1>
  *     <level1>
  *     ...
  *     </level1>
     </root>
  <br/>
    约定 ${}为节点对应nodeName值
    ${root} = dataExchangePackage
    ${level1}==envelopeInfo
    ${level2}==sourceID...
    * @param input
    * @return Map
    * 从map 获取值
    * 如果key    是叶子节点：则返回string,反之,为Map
    * 如果想取sourceID的值，则key=/dataExchangePackage/envelopeInfo/sourceID
    */
   public static Map    reParseRules(String filePath,InputStream input){
     List rules = RuleLoader.getXmlRuleLoader(filePath).parseRules();
     if(rules != null && rules.size()>0){
        Digester digester = new Digester();
      Node root=(Node)rules.get(0); //根节点
      MapSetNextRule rule = new MapSetNextRule( "put");
      addRule2Dister(digester, root,"", rule, true);
         try {
        Map valueMap = new HashMap();
        Map parseMap = (Map)digester.parse(input);
        valueMap.putAll(parseMap);
        afterRootMap(parseMap,valueMap,"");
         return valueMap;
      } catch (IOException e) {
        e.printStackTrace();
      } catch (SAXException e) {
        e.printStackTrace();
      } finally{
        digester= null;
      }
     }
     return null;
  }
    
   private static void afterRootMap(Map valueMap,Map destMap,String pattern){
        String fullPattern="";
        
        Iterator keys = valueMap.keySet().iterator();
       while(keys.hasNext()){
        Object key = keys.next();
        Object v = valueMap.get(key);
        fullPattern= pattern+ "/"+key;
         if(v instanceof Map){
          afterRootMap((Map)v,destMap,fullPattern);
        } else{
          logger.debug(fullPattern+ ">>>>对应元素>"+v+ "    放入返回栈中");
          destMap.put(fullPattern, v);
        }
      }    
  }
    
   private static URL getURL(String resourceLocation){
     try {
       if (resourceLocation.startsWith(ResourceHelper.CLASSPATH_URL_PREFIX)) {
         return ResourceHelper.getURL(resourceLocation);
      } else if(resourceLocation.startsWith(ResourceHelper.FILE_URL_PREFIX)) {
        resourceLocation = StringUtils.replace(resourceLocation, ResourceHelper.FILE_URL_PREFIX, "");
         return new File(resourceLocation).toURI().toURL();
      }
    } catch (Exception e) {
      logger.error( "解析XML路径时,出错");
    }
     return null;
  }
    
    
/**
* 递归添加解析规则
* @param digester
* @param node ：当前节点
* @param pattern:规则
* @param rule:支持map添加
* @param isRoot 是否为根节点
*/
private static void addRule2Dister(Digester digester,Node node,String pattern,MapSetNextRule rule, boolean isRoot){
     String fullPattern="";
     if(StringUtils.isNotBlank(pattern)){
         fullPattern = pattern+ "/"+node.getNodeName();
     } else{
        fullPattern = node.getNodeName();
     }        
     if(node.getChildren().size()>0){
        logger.debug( " add rules >>> digester.addObjectCreate("+fullPattern+ ", HashMap.class);");
        digester.addObjectCreate(fullPattern, HashMap. class);
         if(StringUtils.isNotBlank(node.getAttrs())){
         String[] attrs =StringUtils.split(node.getAttrs(), ",");
         logger.debug(fullPattern+ "有属性:"+ToStringBuilder.reflectionToString(attrs));
         for( int i=0;i<attrs.length;i++){
            String attr= attrs[i];
            logger.debug( " add rules >>> digester.addCallMethod("+fullPattern+ ",\"put\", 2)");
            logger.debug( " add rules >>> digester.addObjectParam("+fullPattern+ ",0, "+attr+ ")");
            logger.debug( " add rules >>> digester.addCallParam("+fullPattern+ ",1, "+attr+ ")");
            digester.addCallMethod(fullPattern, "put", 2);
            digester.addObjectParam(fullPattern, 0, attr);
            digester.addCallParam(fullPattern, 1,attr);            
         }
        }
         if(!isRoot){ //不是根节点
         logger.debug( " add rules >>> digester.addRule("+fullPattern+ ", rule);");
         digester.addRule(fullPattern, rule);
        }
         for( int i=0;i<node.getChildren().size();i++){
         Node child = (Node)node.getChildren().get(i);
         addRule2Dister(digester,child,fullPattern,rule, false);
        }
        
     } else{
         //叶子节点
        logger.debug( "add rules >>> digester.addCallMethod("+fullPattern+ ", \"put\", 2)");
        digester.addCallMethod(fullPattern, "put", 2);
        logger.debug( "add rules >>>    digester.addObjectParam("+fullPattern+ ",0, "+node.getNodeName()+ ")");
        digester.addObjectParam(fullPattern, 0, node.getNodeName());
        logger.debug( "add rules >>> digester.addCallParam("+fullPattern+ ",1)");
        digester.addCallParam(fullPattern, 1);    
     }
    }
...
}

 

XML阅读器

 

public class XmlReader {
   private static final Log logger = LogFactory.getLog(XmlReader. class);
   private String rulePath;
   private String filePath;
   private RuleLoader rule;
   public XmlReader(String rulePath){
     this.rulePath = rulePath;
  }
   public List read(String filePath){
        rule = new RuleLoader( this.rulePath,filePath);
         return rule.parseRules();
  }
...
}

 

 

 测试类

 

     public static void main(String args[]) throws Exception{
      InputStream resourceAsStream = Thread.currentThread().getContextClassLoader().getResourceAsStream( "com/aisino/common/parse/101R.xml");
      Map m = RuleLoader.reParseRules( "classpath:com/aisino/common/parse/xml-value-example.xml",resourceAsStream);
      System.out.println(m.get( "/dataExchangePackage/envelopeInfo/destinationID"));
      System.out.println(m.get( "/dataExchangePackage/transferInfo/age"));
      System.out.println(m.get( "/dataExchangePackage/transferInfo/sex"));
        }

 

测试规则文件（定义XML解析规则）

暂时只支持5级。当然可以无限增加至6级别,8级...

Digester 好想不支持通配符吧。 在这一点确实没有做到充分的可扩展。但是5级相当可以满足应用了

<? xml version ="1.0" ?>
< root nodeName ="dataExchangePackage" >
< level1 nodeName ="envelopeInfo" >
     < level2 nodeName ="sourceID" />
     < level2 nodeName ="destinationID" />
     < level2 nodeName ="destinationAppID" />
     < level2 nodeName ="businessType" />
     < level2 nodeName ="globalBusinessID" />
</ level1 >
< level1 nodeName ="transferInfo" attrs ="age,sex" >
     < level2 nodeName ="senderID" />
     < level2 nodeName ="receiverID" />
     < level2 nodeName ="isRetry" />
     < level2 nodeName ="sendTime" />
     < level2 nodeName ="messageID" />
     < level2 nodeName ="sourceMessageID" />
</ level1 >
< level1 nodeName ="contentControl" >
       < level2 nodeName ="zip" >
         < level3 nodeName ="isZip" />
       </ level2 >
       < level2 nodeName ="encrypt" >
         < level3 nodeName ="isEncrypt" />
       </ level2 >
       < level2 nodeName ="code" >
         < level3 nodeName ="isCode" />
       </ level2 >
</ level1 >
< level1 nodeName ="packageInfo" >
     < level2 nodeName ="subPackage" >
       < level3 nodeName ="sequence" />
       < level3 nodeName ="content" >
         < level4 nodeName ="dj_nsrxx" >
           < level5 nodeName ="nsrsbh" />
           < level5 nodeName ="swjg_dm" />
           < level5 nodeName ="nsrdzdah" />
           < level5 nodeName ="nsrmc" />
           < level5 nodeName ="zjhm" />
           < level5 nodeName ="scjydz" />
           < level5 nodeName ="bsrmc" />
           < level5 nodeName ="dhhm" />
           < level5 nodeName ="djzclx_dm" />
           < level5 nodeName ="nsrzt_dm" />
           < level5 nodeName ="nsr_swjg_dm" />
         </ level4 >
       </ level3 >
     </ level2 >
</ level1 >
< level1 nodeName ="returnState" >
     < level2 nodeName ="returnCode" > </ level2 >
     < level2 nodeName ="returnMessageID" > </ level2 >
     < level2 nodeName ="returnMessage" > </ level2 >
</ level1 >
</ root >

 

测试数据

 

<? xml version ="1.0" encoding ="GBK" ?>
< dataExchangePackage xmlns ="http://www.chinatax.gov.cn/tirip/dataspec" xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation ="http://www.chinatax.gov.cn/tirip/dataspec/dataExchangePackage.xsd" version ="SW5001" >
   < envelopeInfo >
       < sourceID >SJ </ sourceID >
       < destinationID >YD </ destinationID >
       < destinationAppID >SJQZ </ destinationAppID >
       < businessType >WLFP101 </ businessType >
       < globalBusinessID >SJWLFP1012012011100184241 </ globalBusinessID >
     </ envelopeInfo >
   < transferInfo age ="88777" sex ="男" >
         < senderID >SJ </ senderID >
         < receiverID >YD </ receiverID >
         < isRetry />
         < sendTime >2012-01-11 13:14:57:759 </ sendTime >
         < messageID >SJWLFP1012012011100184241 </ messageID >
         < sourceMessageID />
   </ transferInfo >
   < contentControl >
             < zip >
               < isZip >false </ isZip >
             </ zip >
           < encrypt >
             < isEncrypt >false </ isEncrypt >
           </ encrypt >
           < code >
               < isCode >false </ isCode >
           </ code >
   </ contentControl >
   < packageInfo >
         < subPackage >
           < sequence >1 </ sequence >
           < content >
             < dj_nsrxx >
               < nsrsbh >350583729702365 </ nsrsbh >
               < swjg_dm >13505833100 </ swjg_dm > < xgrq />
               < nsrdzdah >350502001008324 </ nsrdzdah >
               < nsrmc >南安市水头康利石材有限公司 </ nsrmc >
               < zjhm >130302610511351 </ zjhm >
               < scjydz >南安市水头镇西锦村 </ scjydz >
               < bsrmc >陈姿颖 </ bsrmc >
               < dhhm >6981988 </ dhhm >
               < djzclx_dm >230 </ djzclx_dm >
               < nsrzt_dm >21 </ nsrzt_dm >
               < nsr_swjg_dm >13505833100 </ nsr_swjg_dm >
             </ dj_nsrxx >
           </ content >
           </ subPackage >
     </ packageInfo >
     < returnState >
             < returnCode >00 </ returnCode >
             < returnMessageID >YDWLFP1012012011100000001 </ returnMessageID >
             < returnMessage >成功 </ returnMessage >
     </ returnState >
</ dataExchangePackage >

 

测试结果

 /dataExchangePackage/envelopeInfo/destinationID>>>>YD
/dataExchangePackage/transferInfo/age>>>88777
/dataExchangePackage/transferInfo/age>>>男