xml的通讯录系统

缺点是一开始做的做的时候没有考虑到面向对象 并没有写出一个Contact类把所有的联系人封装到对象中.

Demo1.java

package cn.itcast.dom4j;


import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

import java.io.File;
import java.io.FileOutputStream;
import java.util.List;
import java.util.Scanner;

/**
 * Created by LiJing on 2017/9/4.
 */
public class Demo1 {
    static Document document = null ;
    static File file =new File("./contact.xml");
    public static void main(String[] args) throws Exception{

        while(true) {
            init();
            select();
            write();
        }
    }
    //初始化
    public static void init()throws Exception{
        document = new SAXReader().read(file);
        System.out.println("*************************************");
        System.out.println("* 1 . 添加联系人                    *");
        System.out.println("* 2 . 修改联系人                    *");
        System.out.println("* 3 . 删除联系人                    *");
        System.out.println("* Q . 查询所有联系人                *");
        System.out.println("*************************************");
    }
    public static void select() throws Exception{
        Scanner scanner = new Scanner(System.in);
        String select = "";
        if(scanner.hasNext()){
            select = scanner.next();
        }
        if("1".equals(select)){
            //添加联系人
            add();
        }else if("2".equals(select)){
            //修改联系人
            gai();
        }else if("3".equals(select)){
            //删除联系人
            String id = null;
            System.out.println("请输入要删除的ID");
            Scanner scanner1  =  new Scanner(System.in);
            if(scanner1.hasNext()){
                id = scanner1.next();
            }
            del(id);
        }else if("q".equalsIgnoreCase(select)) {
            //查询所有联系人
            getAll();
        }else{
            System.out.println("您的输入有误");
        }
    }
    //增加联系人
    public static void add() throws Exception{
        Scanner scanner = new Scanner(System.in);
        String text = null;
        Element rootElem = document.getRootElement();
        Element contactElem = rootElem.addElement("contact");
        Element idElem = contactElem.addElement("id");
        System.out.println("请输入编号");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        contactElem.attribute("id").setText(text);
        Element nameElem = contactElem.addElement("name");
        System.out.println("请输入姓名");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        nameElem.addText(text);
        Element sexElem = contactElem.addElement("sex");
        System.out.println("请输入性别");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        sexElem.addText(text);
        Element ageElem = contactElem.addElement("age");
        System.out.println("请输入年龄");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        ageElem.addText(text);
        Element phoneElem = contactElem.addElement("phone");
        System.out.println("请输入手机号");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        phoneElem.addText(text);
        Element emailElem = contactElem.addElement("email");
        System.out.println("请输入邮箱");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        emailElem.addText(text);
        Element qqElem = contactElem.addElement("qq");
        System.out.println("请输入QQ");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        qqElem.addText(text);
        System.out.println("添加成功");

    }
    public static void del(String id){

        Element rootElem = document.getRootElement();
        List list = rootElem.elements();
        for(Element element:list){
            if(element.element("id").getText().equals(id)){
                element.detach();
            }
        }
        System.out.println("删除成功");
    }
    public static void gai() throws Exception {
        String text = null;
        String id = null ;
        System.out.println("请输入要修改的ID");
        Scanner scanner = new Scanner(System.in);
        if(scanner.hasNext()){
            id =  scanner.next();
        }
        Element contactElem = (Element) document.selectSingleNode("//contact[@id=" + id + "]");

        Element nameElem = contactElem.element("name");
        System.out.println("请输入姓名");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        nameElem.setText(text);
        Element sexElem = contactElem.element("sex");
        System.out.println("请输入性别");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        sexElem.setText(text);
        Element ageElem = contactElem.element("age");
        System.out.println("请输入年龄");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        ageElem.setText(text);
        Element phoneElem = contactElem.element("phone");
        System.out.println("请输入手机号");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        phoneElem.addText(text);
        Element emailElem = contactElem.element("email");
        System.out.println("请输入邮箱");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        emailElem.setText(text);
        Element qqElem = contactElem.element("qq");
        System.out.println("请输入QQ");
        if(scanner.hasNext()){
            text = scanner.next();
        }
        qqElem.setText(text);
        System.out.println("修改成功");
    }

    public static void write() throws Exception{
        //设置输出路径
        FileOutputStream fileOutputStream = new FileOutputStream(file);
        //美观输出
        OutputFormat format = OutputFormat.createPrettyPrint();
        //编码
        format.setEncoding("utf-8");
        //创建
        XMLWriter writer = new XMLWriter(fileOutputStream,format);
        //写出
        writer.write(document);
    }
    //获取所有联系人
    public static void getAll(){
        String xpath = "//contact";
        List list =document.selectNodes(xpath);
        System.out.println("编号  姓名      性别      年龄          电话            邮箱                        QQ");
        for(Element element:list){

            //获取到的是tr节点 然后获取子节点的文本 需要强转
            System.out.print(element.attributeValue("id"));
            System.out.print("    "+((Element) element.elements().get(0)).getText());
            System.out.print("    " + ((Element) element.elements().get(1)).getText());
            System.out.print("     "+((Element)element.elements().get(2)).getText());
            System.out.print("       " + ((Element) element.elements().get(3)).getText());
            System.out.print("             " + ((Element) element.elements().get(4)).getText());
            System.out.println("    "+((Element)element.elements().get(5)).getText());;

        }
    }
}

contact.xml

<contactList> 
  <contact id="001"> 
    <name>lijingname>  
    <sex>nnasex>  
    <age>14age>  
    <phone>1232224451phone>  
    <email>[email protected]email>  
    <qq>123456qq> 
  contact>  
  <contact id="002"> 
    <name>张三name>  
    <sex>男sex>  
    <age>18age>  
    <phone>123111123123123123phone>  
    <email>[email protected]email>  
    <qq>123444444qq> 
  contact> 
contactList>