Dom4j using XPath to navigate directly to a tag instance when parsing xml

It Programmer development Essentials-all kinds of resources download list, history of the most IT resources, personal collection summary. package edu.dom4j.dom;

Import java.util.List;

Import org.dom4j.Document;

Import org.dom4j.DocumentException;

Import org.dom4j.Element;

Import Org.dom4j.Node;

Import Org.dom4j.io.SAXReader;

Import Org.junit.Test;

public class Xpathreadxml {

Private String Xmlfile1 = "Webroot/product2.xml";

Private String Xmlfile2 = "Webroot/users.xml";

Public Document getdocument (String xmlfile) throws documentexception{

Saxreader reader = new Saxreader ();

Return Reader.read (xmlfile);

}

Read <product> bottom <price> text value

@Test

public void ReadText () throws documentexception{

Document document = GetDocument (Xmlfile1);

If the path is preceded by a slash/start, then the path represents the absolute path to an element

String xmlPath1 = "/catalog/product/price";

If the path begins with a double slash////, then all elements in the document that meet the double slash//after rule (regardless of hierarchy) are selected

String xmlPath2 = "//price";

List<element> pricelist = Document.selectnodes (xmlPath1);

for (Element price:pricelist) {

System.out.println ("<" +price.getname () + ">" +price.gettext () + "</" +price.getname () + ">");

}

System.out.println ("-------------------");

Element product1 = Document.getrootelement (). Element ("Product");

The effect of Product1 is the same as the document query.

Pricelist = Product1.selectnodes (xmlPath1);

for (Element price:pricelist) {

System.out.println ("<" +price.getname () + ">" +price.gettext () + "</" +price.getname () + ">");

}

System.out.println ("-------------------");

Element Price1 = (Element) Document.selectsinglenode (XMLPATH1);

if (price1!=null)

System.out.println ("<" +price1.getname () + ">" +price1.gettext () + "</" +price1.getname () + ">");

System.out.println ("-------------------");

Price1 = (Element) document.selectsinglenode (xmlPath2);

System.out.println ("<" +price1.getname () + ">" +price1.gettext () + "</" +price1.getname () + ">");

System.out.println ("-------------------");

Pricelist = Document.selectnodes (xmlPath2);

for (Element price:pricelist) {

System.out.println ("<" +price.getname () + ">" +price.gettext () + "</" +price.getname () + ">");

}

/**

* Output Result:

<price>80.0</price>

<price>100.0</price>

-------------------

<price>80.0</price>

<price>100.0</price>

-------------------

<price>80.0</price>

-------------------

<price>80.0</price>

-------------------

<price>80.0</price>

<price>100.0</price>

**/

}

Verify that the user is logged on successfully

@Test

public void Validelogin () throws documentexception{

Document document = GetDocument (Xmlfile2);

String username = "AAA";

String password = "Aaapass";

String Xmlpath = "//user[@name = '" "+username+" ' and @password = ' "+password+" '] ";

Node node = document.selectsinglenode (Xmlpath);

if (node!=null) {

System.out.println ("landed successfully. ");

}else {

System.out.println ("User name and password does not exist. ");

}

}

}

product2.xml File:

<?xml version= "1.0" encoding= "Utf-8"?>

<catalog id= "Cata1" >

<product category= "Handtool" inventory= "Instock" >

<specifications weight= "2.0kg" > Wrench </specifications>

<price street= "Hong Kong Street" >80.0</price>

<notes> This is the wrench </notes>

</product>

<product category= "Table" >

<specifications> Tables </specifications>

<price street= "Macau Street" wholesale= "part" >100.0</price>

</product>

</catalog>

users.xml File:

<?xml version= "1.0" encoding= "Utf-8"?>

<users>

<user name= "AAA" password= "Aaapass" ></user>

<user name= "BBB" password= "Bbbpass" ></user>

<user name= "CCC" password= "Cccpass" ></user>

<user name= "ddd" password= "Dddpass" ></user>

</users>

For the use of XPath positioning see : Xpathtutorial.chm (Download address: http://download.csdn.net/detail/xh16319/4587406)