dom编码练习

红太狼 2022-05-09 02:58 133阅读 0赞

一、解析xml文件的dom代码
    
    package com.dom;
    
    import org.w3c.dom.Document;
    import org.w3c.dom.Element;
    import org.w3c.dom.Node;
    import org.w3c.dom.NodeList;
    import org.xml.sax.SAXException;
    
    import javax.xml.parsers.DocumentBuilder;
    import javax.xml.parsers.DocumentBuilderFactory;
    import javax.xml.parsers.ParserConfigurationException;
    import java.io.File;
    import java.io.IOException;
    
    /**
     * Created by yp-tc-m-2935 on 18/9/29.
     * dom编码
     * 思路:先获取大节点元素,遍历该节点元素,得到每个子节点元素,再次遍历该子节点元素
     * 之至到莫节点元素,获取该元素的textcontent值
     */
    public class dom {
        public static void main(String [] args) throws ParserConfigurationException, IOException, SAXException {
            //1 创建JAXPDOM 解析器工厂(没有具体的实现类,需newinstance一个)
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            //2 根据工厂获取解析器
            DocumentBuilder builder = factory.newDocumentBuilder();
            //3 使用解析器解析文档得到Document对象
            Document document = builder.parse(new File("/Users/yp-tc-m-2935/Documents/mavenProject/servletTest/src/main/java/com/dom/student.xml"));
            //拿到所有的学生并打印学生信息
            //1 获得所有student元素对象
            NodeList students = document.getElementsByTagName("student");
            //2 遍历这些对象,取得number属性
            for(int i=0;i<students.getLength();i++){
    //            if(students.item(i) instanceof Element){
    //                Element student =(Element)students.item(i);  //是一个一个的student元素
    //            }
                if(students.item(i).getNodeType()== Node.ELEMENT_NODE){ //如果是一个student元素
                    Element student =(Element)students.item(i);
                    String number =student.getAttribute("number");
                    //3取得子元素,遍历子元素
    
                    NodeList list = student.getChildNodes();
                    for(int x=0;x<list.getLength();x++){
                        if(list.item(x).getNodeType() == Node.ELEMENT_NODE){
                        //获取的可能是name  age   sex
                        Element info =  (Element)list.item(x);
                        if(info.getNodeName().equals("name")){
                           System.out.print(info.getTextContent()+",");   //获取name的文本值
                        }else if(info.getNodeName().equals("sex")){
                            System.out.print(info.getTextContent()+",");
                        }else if(info.getNodeName().equals("age")){
                            System.out.println(info.getTextContent());
    
                        }
                        }
                    }
                }
    
            }
        }
    }

2、xml文件内容

<?xml version="1.0" encoding="UTF-8"?>
    
    <students>
        <student number="IDTEST01">
            <name>tom</name>
            <sex>男</sex>
            <age>10</age>
        </student>
        <student number="IDTEST02">
            <name>Jennery</name>
            <sex>女</sex>
            <age>10</age>
        </student>
    </students>