dom4j的学习

dom4j 是一种解析 XML 文档的开放源代码 XML 框架。

参考google所有出来的关于dom4j的例子，自己学着写了两个范例，想用它来写文件存储器的索引文件。

1、首先下载dom4j的包，可以到http://dom4j.sourceforge.net/网站下载。

2、创建Document。

public Document createDocument() {     Document document = DocumentHelper.createDocument();     document.addComment("索引文件管理列表！");     Element root = document.addElement( "Root" );     Element sysDir1 = root.addComment("存储文件工作目录")         .addElement( "SysDir" ).addText("C:\\document\\aa\\");     for(int i = 0;i<5;i++)     {         String guid = "***"+i;         Element task1 = root.addElement( "Task" );         Element guid1 = task1.addElement("GUID").addText(guid);         Element proir1 = task1.addElement("Proir").addText((i+2)+"");         Element status1 = task1.addElement("Status").addText((i+5)+"");         Element isSend1 = task1.addElement("IsSend").addText("true");     }     return document; }

3、生成XML文件。

public boolean CreatXML(Document doc) {     boolean ret = false;     try     {         //输出数据到XML文件中         OutputFormat format = OutputFormat.createPrettyPrint();         //xml文件字符集为GBK         format.setEncoding("GBK");         FileOutputStream fos = new FileOutputStream("d:\\content.xml");         BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(fos , "GBK"));         XMLWriter writer = new XMLWriter(bw , format);         writer.write(doc);         bw.close();         ret = true;     }catch(Exception ex)     {         System.out.println(ex.toString());     }     return ret; }

4、读取XML文件。

public Document read(String fileName) throws MalformedURLException, DocumentException {     SAXReader reader = new SAXReader();     Document document = reader.read(new File(fileName));     return document; }

5、测试例子

public static void main(String s[]) {     dom4jmain xml=new dom4jmain();     Document doc = xml.createDocument();     xml.CreatXML(doc);                  try     {         Document doc1 = xml.read("D:\\content.xml");         Element root = xml.getRootElement(doc1);         boolean isDel = false;         for(int i =0; i < root.nodeCount(); i ++)         {             Node node = root.node(i);             String nodexml = node.asXML();             if(nodexml.trim().equals("")) continue;                          if (node instanceof Element)             {                 if(node.getName().equals("Task"))                 {                     System.out.println("///////////////////////");                     System.out.println(node.asXML());                     Element enode = (Element)node;                     String guid = "";                     for(int j =0; j < enode.nodeCount(); j ++)                     {                         Node chnode = enode.node(j);                         nodexml = chnode.asXML();                         if(nodexml.trim().equals("")) continue;                                                  //获取GUID                         if(chnode.getName().equals("GUID"))                         {                             guid = chnode.getText();                         }                                                  //修改属性                         if(guid.equals("***1") && chnode.getName().equals("IsSend"))                         {                             chnode.setText("false");                         }                                                  //删除节点设置                         if(guid.equals("***2"))                         {                             isDel = true;                         }                         System.out.println("＜Task＞"+chnode.getName()+"="+chnode.getText());                     }                 }                 else if(node.getName().equals("SysDir"))                 {                     System.out.println("＜SysDir＞"+node.getName()+"="+node.getText());                                 }             }                          //删除节点             if(isDel)             {                 root.remove(node);                 isDel = false;             }         }                  //增加节点         Element task1 = root.addElement( "Task" );             Element guid1 = task1.addElement("GUID").addText("newguid");         Element proir1 = task1.addElement("Proir").addText("0");         Element status1 = task1.addElement("Status").addText("a");         Element isSend1 = task1.addElement("IsSend").addText("true");                  xml.CreatXML(doc1);     }     catch(Exception ex)     {}         }

6、附：测试的两个文件，dom4jmain.java和dom4jtest.java
dom4jmain.java 文件。

import org.dom4j.*; import org.dom4j.io.OutputFormat; import org.dom4j.io.XMLWriter; import org.dom4j.io.SAXReader; import java.io.*; import java.net.*; public class dom4jmain {     public dom4jmain()     {     }     public Document createDocument()     {             Document document = DocumentHelper.createDocument();         document.addComment("索引文件管理列表！");         Element root = document.addElement( "Root" );         Element sysDir1 = root.addComment("存储文件工作目录")             .addElement( "SysDir" ).addText("C:\\document\\aa\\"); for(int i = 0;i<5;i++) {     String guid = "***"+i;     Element task1 = root.addElement( "Task" );         Element guid1 = task1.addElement("GUID").addText(guid);     Element proir1 = task1.addElement("Proir").addText((i+2)+"");     Element status1 = task1.addElement("Status").addText((i+5)+"");     Element isSend1 = task1.addElement("IsSend").addText("true"); } return document;     }          public boolean CreatXML(Document doc)     {         boolean ret = false;         try         {             //输出数据到XML文件中             OutputFormat format = OutputFormat.createPrettyPrint();             //xml文件字符集为GBK             format.setEncoding("GBK");             FileOutputStream fos = new FileOutputStream("d:\\content.xml");             BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(fos , "GBK"));             XMLWriter writer = new XMLWriter(bw , format);             writer.write(doc);             bw.close();             ret = true;         }catch(Exception ex)         {             System.out.println(ex.toString());         }         return ret;     }          public Document read(String fileName) throws MalformedURLException, DocumentException     {         SAXReader reader = new SAXReader();         Document document = reader.read(new File(fileName));         return document;              }          public Element getRootElement(Document doc)     {         return doc.getRootElement();     } }

dom4jtest.java 文件。

import org.dom4j.Document; import org.dom4j.Element; import org.dom4j.Node; public class dom4jtest {     public static void main(String s[])     {         dom4jmain xml=new dom4jmain();         Document doc = xml.createDocument();         xml.CreatXML(doc);                          try         {             Document doc1 = xml.read("D:\\content.xml");             Element root = xml.getRootElement(doc1);             boolean isDel = false;             for(int i =0; i < root.nodeCount(); i ++)             {                 Node node = root.node(i);                 String nodexml = node.asXML();                 if(nodexml.trim().equals("")) continue;                                  if (node instanceof Element)                 {                     if(node.getName().equals("Task"))                     {                         System.out.println("///////////////////////");                         System.out.println(node.asXML());                         Element enode = (Element)node;                         String guid = "";                         for(int j =0; j < enode.nodeCount(); j ++)                         {                             Node chnode = enode.node(j);                             nodexml = chnode.asXML();                             if(nodexml.trim().equals("")) continue;                                                          //获取GUID                             if(chnode.getName().equals("GUID"))                             {                                 guid = chnode.getText();                             }                                                          //修改属性                             if(guid.equals("***1") && chnode.getName().equals("IsSend"))                             {                                 chnode.setText("false");                             }                                                          //删除节点设置                             if(guid.equals("***2"))                             {                                 isDel = true;                             }                             System.out.println("＜Task＞"+chnode.getName()+"="+chnode.getText());                         }                     }                     else if(node.getName().equals("SysDir"))                     {                         System.out.println("＜SysDir＞"+node.getName()+"="+node.getText());                                     }                 }                                  //删除节点                 if(isDel)                 {                     root.remove(node);                     isDel = false;                 }             }                          //增加节点             Element task1 = root.addElement( "Task" );          Element guid1 = task1.addElement("GUID").addText("newguid");      Element proir1 = task1.addElement("Proir").addText("0");      Element status1 = task1.addElement("Status").addText("a");      Element isSend1 = task1.addElement("IsSend").addText("true");                          xml.CreatXML(doc1);         }         catch(Exception ex)         {}             } }

7、测试结果
打印出下面的输出结果，同时会在D:\下创建一个content.xml的文件。

＜SysDir＞SysDir=C:\document\aa\ /////////////////////// ＜Task＞         ＜GUID＞***0＜/GUID＞         ＜Proir＞2＜/Proir＞         ＜Status＞5＜/Status＞         ＜IsSend＞true＜/IsSend＞     ＜/Task＞ ＜Task＞GUID=***0 ＜Task＞Proir=2 ＜Task＞Status=5 ＜Task＞IsSend=true /////////////////////// ＜Task＞         ＜GUID＞***1＜/GUID＞         ＜Proir＞3＜/Proir＞         ＜Status＞6＜/Status＞         ＜IsSend＞true＜/IsSend＞     ＜/Task＞ ＜Task＞GUID=***1 ＜Task＞Proir=3 ＜Task＞Status=6 ＜Task＞IsSend=false /////////////////////// ＜Task＞         ＜GUID＞***2＜/GUID＞         ＜Proir＞4＜/Proir＞         ＜Status＞7＜/Status＞         ＜IsSend＞true＜/IsSend＞     ＜/Task＞ ＜Task＞GUID=***2 ＜Task＞Proir=4 ＜Task＞Status=7 ＜Task＞IsSend=true /////////////////////// ＜Task＞         ＜GUID＞***3＜/GUID＞         ＜Proir＞5＜/Proir＞         ＜Status＞8＜/Status＞         ＜IsSend＞true＜/IsSend＞     ＜/Task＞ ＜Task＞GUID=***3 ＜Task＞Proir=5 ＜Task＞Status=8 ＜Task＞IsSend=true /////////////////////// ＜Task＞         ＜GUID＞***4＜/GUID＞         ＜Proir＞6＜/Proir＞         ＜Status＞9＜/Status＞         ＜IsSend＞true＜/IsSend＞     ＜/Task＞ ＜Task＞GUID=***4 ＜Task＞Proir=6 ＜Task＞Status=9 ＜Task＞IsSend=true