DOM解析XML文件步骤如下：

DocumentBuilderFactory--->DocumentBuilder-->Document 【builder.parse()】

Document 获取节点的文本内容，并且输出

import java.io.File;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;


import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;


public class XMlReaderTest {
	/**
	 * factory ------->build------------->doc--->nodelist------------->node------------->value
	 * newInstance  newDocumentBuilder   parse   getElementByTagName  item,getFirstChild  getNodeValue
	  */
	public static void main(String[] args) {
//建立DocumentBuilderFactory ，以获取DocumentBuilder
		    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
			DocumentBuilder builder  = null;
			Document doc  = null;

		try {
//建立DocumentBulider,以获取Document
			 builder = factory.newDocumentBuilder();
			 doc=builder.parse("c:"+File.separator+"123.xml");
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		NodeList nl  = doc.getElementsByTagName("linkman");
		for(int i=0 ;i<nl.getLength();i++){
			Element e  = (Element)nl.item(i);
			String  name=e.getElementsByTagName("name").item(0).getFirstChild().getNodeValue();
			String  tel=e.getElementsByTagName("tel").item(0).getFirstChild().getNodeValue();
			System.out.println("姓名："+name+",电话号码："+tel);
		}
		
	}

}