Add, delete, modify, and query xml node attributes in java

Add, delete, modify, and query xml node attributes in java

Before learning this article, please read my other article. JAVA provides a better understanding of XML operations on XML nodes.

1 package vastsum; 2 3 import java. io. file; 4 import java. io. fileWriter; 5 import java. util. iterator; 6 7 import org. dom4j. attribute; 8 import org. dom4j. document; 9 import org. dom4j. element; 10 import org. dom4j. io. SAXReader; 11 import org. dom4j. io. XMLWriter; 12 import org. junit. test; 13 14/** 15 * use dom4j to operate xml16 * to operate xml properties 17 * Time: October 18 * the xml file operated is contact. xml19 * the file name is attrDemo. java20 * @ author shutu00821 * 22 */23 public class attrDemo {24 @ Test25 public void exmple () throws Exception {26 // read the XML file, obtain the document Object 27 SAXReader reader = new SAXReader (); 28 Document document = reader. read (new File (". /src/contact. xml "); 29 30 // get the attribute object 31 Element rootElem = document for a node. getRootElement (); 32 // get the root node Attribute object 33 Attribute rootAttr = rootElem. attribute ("id"); 34 35 // get the attribute object 36 Element contactElem = rootElem of the specified node. element ("contact"); 37 Attribute contactAttr = contactElem. attribute ("id"); 38 39 // traverse all attributes of a node 40 for (Iterator it = contactElem. attributeIterator (); it. hasNext ();) {41 Attribute conAttr = (Attribute) it. next (); 42 String conTxt = conAttr. getValue (); 43 String conAttrName = conAttr. getName (); 44 System. out. println (conAttrName + "=" + conTxt); 45} 46 // set the attributes and values of a node 47 contactElem. addAttribute ("name", "zhangsan"); 48 49 // set (Change) the value of an Attribute 50 Attribute nameAttr = contactElem. attribute ("name"); 51 nameAttr. setValue ("lisi"); 52 53 // delete a node's specified attribute 54 contactElem. remove (nameAttr); 55 // write the attributes and values of a node to 56 XMLWriter writer = new XMLWriter (new FileWriter (". /src/contact. xml "); 57 writer. write (document); 58 writer. close (); 59 60/** 61 * If the document contains Chinese characters, you need to set the character encoding 62 * using the following statement: 63 * OutputFormat format = OutputFormat. createPrettyPrint (); 64 * format. setEncoding ("GBK"); 65 * XMLWriter writer = new XMLWriter (new FileWriter (". /src/contact. xml "), format); 66 */67 // get the attribute name of the specified object 68 System. out. println (rootAttr. getName (); 69 System. out. println (contactAttr. getName (); 70 // get the attribute value of the specified object 71 System. out. println (contactAttr. getValue (); 72 System. out. println (rootAttr. getValue (); 73} 74}

Note: The above sample code can be run directly. You can use Junit 4 to adjust the code in this example.

The following is an XML document:

1 <? Xml version = "1.0" encoding = "UTF-8"?> 2 <contactList id = "0"> 3 <contact id = "001" class = "style"> 4 <name> Zhang San </name> 5 <age> 20 </age> 6 <phone> 134222223333 </phone> 7 <email> zhangsan@qq.com </email> 8 <qq> 432221111 </qq> 9 </contact> 10 <contact id = "002 "> 11 <name> Li Si </name> 12 <age> 20 </age> 13 <phone> 134222225555 </phone> 14 <email> lisi@qq.com </email> 15 <qq> 432222222 </qq> 16 </contact> 17 <contactTwo> 18 <name> Wang Wu </name> 19 <age> 32 </age> 20 <phone> 465431341 </phone> 21 <emali> af@qq.com </emali> 22 <qq> 46164694 </qq> 23 </contactTwo> 24 <test> test </test> 25 <test> Other purpose </test> 26 </contactList>View Code

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