dom解析xml文件可以找得到，解析不出结果，具体见正文

Question

读取程序---------------------------------------------------------------------------------------------------
package com.yuyi.xml;import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import org.w3c.dom.*;import javax.xml.parsers.*;public class XmlUtil { public Document getDocument(String path){
try{
File file = new File(path);
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
System.out.println("factory: "+factory);
DocumentBuilder builder = factory.newDocumentBuilder(); 
System.out.println("builder: "+builder);
Document doc = builder.parse(file);
System.out.println("doc:"+ doc);
BufferedReader br = new BufferedReader(new FileReader(file));
String context;
while((context = br.readLine())!=null){
System.out.println(context);
}
System.out.println("doc: "+doc);
return doc;
}catch(Exception e){
e.printStackTrace();
return null;
}
} public static void main(String[] args) { XmlUtil xmlUtil = new XmlUtil();
String path = "./src/bean.xml";
Document doc = xmlUtil.getDocument(path);
System.out.println("doc: "+doc);
}
}XML文件---------------------------------------------------------------------------------------------------
<?xml version="1.0" encoding="gbk"?><users><user id="0"><name>zhangsan</name><password>lisi</password></user></users>运行结果---------------------------------------------------------------------------------------------------
factory: com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderFactoryImpl@1172e08
builder: com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl@186db54
doc:[#document: null]
<?xml version="1.0" encoding="gbk"?><users><user id="0"><name>zhangsan</name><password>lisi</password></user></users>doc: [#document: null]

Answer 1

package dom;import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.w3c.dom.Element;
import java.io.File;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;/**
 * DOM解析XML文档示例
 */
public class DOMParser {
    public DOMParser() {
    }
    public static void main(String[] args) throws Exception{
        DOMParser domparser = new DOMParser();
        domparser.parseXMLFile("src/file/student.xml");
    }
    /**
     * 解析文档
     * @param fileName
     */
    public void parseXMLFile(String fileName) throws Exception{
            File file = new File(fileName);
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = factory.newDocumentBuilder();
            Document doc = builder.parse(file);
            doc.normalize();            //获得根元素StudentInfo
            Element elmtInfo = doc.getDocumentElement();            //得到所有student元素
            NodeList nlStudent = elmtInfo.getElementsByTagName("student");            System.out.println("XML文件开始解析--By DOM");
            System.out.println();            //循环输出每一个学生成绩
            for (int i = 0; i < nlStudent.getLength(); i++) {                //当前student元素
                Element elmtStudent = (Element) nlStudent.item(i);                NodeList nlCurrent = elmtStudent.getElementsByTagName("name");
                System.out.println("姓名:" +
                                   nlCurrent.item(0).getFirstChild().
                                   getNodeValue());
                nlCurrent = elmtStudent.getElementsByTagName("sex");
                System.out.println("性别:" +
                                   nlCurrent.item(0).getFirstChild().
                                   getNodeValue());                nlCurrent = elmtStudent.getElementsByTagName("lesson");                for (int j = 0; j < nlCurrent.getLength(); j++) {                    Element elmtLesson = (Element) nlCurrent.item(j);
                    NodeList nlLesson = elmtLesson.getElementsByTagName(
                            "lessonName");
                    System.out.print(nlLesson.item(0).getFirstChild().
                                     getNodeValue());
                    System.out.print(":");
                    nlLesson = elmtLesson.getElementsByTagName("lessonScore");
                    System.out.print(nlLesson.item(0).getFirstChild().
                                     getNodeValue());
                    System.out.println();
                }
                System.out.println("------------------------------------");
            }            System.out.println("XML文件解析结束--By DOM");
    }
}
student.xml<?xml version="1.0" encoding="GBK"?><StudentInfo>
    <student>
        <name>乔聪</name>
        <sex>男</sex>
        <lesson>
            <lessonName>Java初级</lessonName>
            <lessonScore>85</lessonScore>
        </lesson>
        <lesson>
            <lessonName>Oracle数据库</lessonName>
            <lessonScore>95</lessonScore>
        </lesson>
        <lesson>
            <lessonName>Java中级</lessonName>
            <lessonScore>80</lessonScore>
        </lesson>
        <lesson>
            <lessonName>Java高级</lessonName>
            <lessonScore>100</lessonScore>
        </lesson>
        <lesson>
            <lessonName>绣花课</lessonName>
            <lessonScore>7</lessonScore>
        </lesson>
        <lesson>
            <lessonName>跳绳课</lessonName>
            <lessonScore>3</lessonScore>
        </lesson>
    </student>
    <breakLine/>
    <student>
        <name>花木兰</name>
        <sex>女</sex>
        <lesson>
            <lessonName>射箭</lessonName>
            <lessonScore>100</lessonScore>
        </lesson>
        <lesson>
            <lessonName>柔道</lessonName>
            <lessonScore>95</lessonScore>
        </lesson>
        <lesson>
            <lessonName>国学</lessonName>
            <lessonScore>80</lessonScore>
        </lesson>
        <lesson>
            <lessonName>烹饪</lessonName>
            <lessonScore>60</lessonScore>
        </lesson>
        <lesson>
            <lessonName>游泳</lessonName>
            <lessonScore>70</lessonScore>
        </lesson>
    </student>
    <breakLine/>
</StudentInfo>

Answer 2

路径没问题，问题是sysout就是[Element: null]并不是没找到，找到了节点组，需要往下细化查找。
同样谢谢各位。散分。