Android 学习心得(1)——pull解析器

　　Android内核使用pull解析器  所以不用导入jar包，pull解析器简单、易用、接近于手工编写XML文件

　　解析的XML文件为xmlpull.xml

　　

<?xml version="1.0" encoding="utf-8"?>
<students>
    <student id="1">
        <name>张MM</name>
        <gender>女</gender>
        <age>18</age>
    </student>
    <student id="2">
        <name>王GG</name>
        <gender>男</gender>
        <age>20</age>
    </student>
</students>

　　实体类student.java

public class student {
    private Integer id;
    private String name;
    private String gender;
    private Integer age;
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getGender() {
        return gender;
    }
    public void setGender(String gender) {
        this.gender = gender;
    }
    public Integer getAge() {
        return age;
    }
    public void setAge(Integer age) {
        this.age = age;
    }
    
}

　

　解析xml的读写方法xmlService.java

package com.bwl.service;

import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlSerializer;

import com.bwl.pojo.student;

import android.util.Xml;

public class xmlService {

    public List<student> read(InputStream xml) throws Exception {
        List<student> list = null;
        student student = null;
        XmlPullParser xmlPull = Xml.newPullParser();
        xmlPull.setInput(xml, "UTF-8");// 设置解析值 （"路径","编码"）
        int flag = xmlPull.getEventType();// 取得当前所指向的数据的事件类型
        do {
            switch (flag) {
            case XmlPullParser.START_DOCUMENT:// xml文档开始节点 start document
                // 集合实例化
                list = new ArrayList<student>();
                break;
            case XmlPullParser.START_TAG:// xml文档开始节点解析
                if ((xmlPull.getName()).equals("student")) {// 和节点内容进行比较
                    int id = new Integer(xmlPull.getAttributeValue(0));// 获取节点的第一个属性值
                    student = new student();
                    student.setId(id);
                }
                if ((xmlPull.getName()).equals("name")) {
                    String name=xmlPull.nextText();// 取得节点的下一个Text节点
                    student.setName(name);
                }
                if ((xmlPull.getName()).equals("gender")) {
                    String gender=xmlPull.nextText();
                    student.setGender(gender);
                }
                if ((xmlPull.getName()).equals("age")) {
                    int age=new Integer(xmlPull.nextText());
                    student.setAge(age);
                }
                break;
            case XmlPullParser.END_TAG:// xml结束节点 end document
                if (xmlPull.getName().equals("student")) {// 节点结束判断
                    list.add(student);// student添加到list集合中
                    student = null;// student置为空
                }
                break;
            }
            flag = xmlPull.next();// 指向下一个节点
        } while (flag != XmlPullParser.END_DOCUMENT); // 执行到END DOCUMENT节点文档结束
        xml.close();
        return list;
    }

    public void write(List<student> list) throws Exception {
        XmlSerializer xmlSerializer = Xml.newSerializer();
        if (list != null) {
            xmlSerializer.startDocument("UTF-8", true);//添加statrt docunment事件
            xmlSerializer.startTag("", "students");//添加节点，参数（命名空间，节点名称）不使用命名空间的话可以使用""代替
            for (student student : list) {
                xmlSerializer.setProperty("", "student");
                xmlSerializer.attribute("", "id", student.getId().toString());//定义student节点胡属性参数：（命名空间，属性名，属性值）
                xmlSerializer.setProperty("", "name");
                xmlSerializer.text(student.getName());
                xmlSerializer.endTag("", "student");//节点结束标记
                xmlSerializer.setProperty("", "gender");
                xmlSerializer.text(student.getGender());
                xmlSerializer.endTag("", "gender");
                xmlSerializer.setProperty("", "age");
                xmlSerializer.text(student.getAge().toString());
                xmlSerializer.endTag("", "age");
                xmlSerializer.endTag("", "student");
            }
            xmlSerializer.endDocument();//添加END DOCUMENT事件

        }
    }

}