package com.example.xmlpaserutil.util;
import java.io.InputStream;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;
import org.xmlpull.v1.XmlPullParser;
import android.util.Log;
import android.util.Xml;
public class XmlUtil<T> {
/**
* 解析XML轉(zhuǎn)換成對(duì)象
*
* @param is
*      輸入流
* @param clazz
*      對(duì)象Class
* @param fields
*      字段集合一一對(duì)應(yīng)節(jié)點(diǎn)集合
* @param elements  //d（這兩行標(biāo)紅，是因?yàn)檫@兩個(gè)是java中字段和xml文件中的字段對(duì)應(yīng)）隊(duì)醫(yī)
*      節(jié)點(diǎn)集合一一對(duì)應(yīng)字段集合
* @param itemElement
*      每一項(xiàng)的節(jié)點(diǎn)標(biāo)簽
* @return
*/
//靜態(tài)方法中加入泛型，需要申明<T>，如果不是對(duì)泛型不是很熟悉，可以先用Object代替，然后再換回來
public static <T> List<T> parse(InputStream is, Class<T> clazz,
List<String> fields, List<String> elements, String itemElement) {
Log.v("rss", "開始解析XML.");
List<T> list = new ArrayList<T>();
try {
XmlPullParser xmlPullParser = Xml.newPullParser();
xmlPullParser.setInput(is, "UTF-8");
int event = xmlPullParser.getEventType();
T obj = null;
while (event != XmlPullParser.END_DOCUMENT) {
switch (event) {
case XmlPullParser.START_TAG:
if (itemElement.equals(xmlPullParser.getName())) {
obj = clazz.newInstance();
}
if (obj != null
&& elements.contains(xmlPullParser.getName())) {
setFieldValue(obj, fields.get(elements
.indexOf(xmlPullParser.getName())),
xmlPullParser.nextText());
}
break;
case XmlPullParser.END_TAG:
if (itemElement.equals(xmlPullParser.getName())) {
list.add(obj);
obj = null;
}
break;
}
event = xmlPullParser.next();
}
} catch (Exception e) {
Log.e("rss", "解析XML異常：" + e.getMessage());
throw new RuntimeException("解析XML異常：" + e.getMessage());
}
return list;
}
/**
* 設(shè)置字段值
*
* @param propertyName
*      字段名
* @param obj
*      實(shí)例對(duì)象
* @param value
*      新的字段值
* @return
*/
public static void setFieldValue(Object obj, String propertyName,
Object value) {
try {
Field field = obj.getClass().getDeclaredField(propertyName);
field.setAccessible(true);
field.set(obj, value);
} catch (Exception ex) {
throw new RuntimeException();
}
}
}

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
InputStream in = null;
try {
in =getResources().getAssets().open("User.xml");
//如果說要獲取到File對(duì)象的話，獲取assert文件中的文件
//File file =new File("file:///android_asset/User.xml");
} catch (Exception e) {
e.printStackTrace();
}
List <String > fields =new ArrayList<String>();
List <String > elements =new ArrayList<String>();
fields.add("name");
fields.add("age");
elements.add("name");
elements.add("age");
List<User> users = XmlUtil.parse(in, User.class, fields, elements, "User");
for (Object object : users) {
System.out.println(object.toString());
}
}

<?xml version="1.0" encoding="UTF-8"?>
<Users>
 <User>
  <name>張三</name>
  <age>20</age>
 </User>
 <User>
  <name>李四</name>
  <age>21</age>
 </User>
 <User>
  <name>王五</name>
  <age>22</age>
 </User>
</Users>

/**
 * 解析XML工具類
 */
public class XmlUtils {
  /**
   * 解析XML轉(zhuǎn)換成對(duì)象
   *
   * @param is
   *      輸入流
   * @param clazz
   *      對(duì)象Class
   * @param fields
   *      字段集合一一對(duì)應(yīng)節(jié)點(diǎn)集合
   * @param elements
   *      節(jié)點(diǎn)集合一一對(duì)應(yīng)字段集合
   * @param itemElement
   *      每一項(xiàng)的節(jié)點(diǎn)標(biāo)簽
   * @return
   */
  public static List<Object> parse(InputStream is, Class<?> clazz,
      List<String> fields, List<String> elements, String itemElement) {
    Log.v("rss", "開始解析XML.");
    List<Object> list = new ArrayList<Object>();
    try {
      XmlPullParser xmlPullParser = Xml.newPullParser();
      xmlPullParser.setInput(is, "UTF-8");
      int event = xmlPullParser.getEventType();
      Object obj = null;
      while (event != XmlPullParser.END_DOCUMENT) {
        switch (event) {
        case XmlPullParser.START_TAG:
          if (itemElement.equals(xmlPullParser.getName())) {
            obj = clazz.newInstance();
          }
          if (obj != null
              && elements.contains(xmlPullParser.getName())) {
            setFieldValue(obj, fields.get(elements
                .indexOf(xmlPullParser.getName())),
                xmlPullParser.nextText());
          }
          break;
        case XmlPullParser.END_TAG:
          if (itemElement.equals(xmlPullParser.getName())) {
            list.add(obj);
            obj = null;
          }
          break;
        }
        event = xmlPullParser.next();
      }
    } catch (Exception e) {
      Log.e("rss", "解析XML異常：" + e.getMessage());
      throw new RuntimeException("解析XML異常：" + e.getMessage());
    }
    return list;
  }
  /**
   * 設(shè)置字段值
   *
   * @param propertyName
   *      字段名
   * @param obj
   *      實(shí)例對(duì)象
   * @param value
   *      新的字段值
   * @return
   */
  public static void setFieldValue(Object obj, String propertyName,
      Object value) {
    try {
      Field field = obj.getClass().getDeclaredField(propertyName);
      field.setAccessible(true);
      field.set(obj, value);
    } catch (Exception ex) {
      throw new RuntimeException();
    }
  }
}

public class User{
 private String name;
 private String age;
 get...set...
}

<Users>
 <User>
  <name>張三</name>
  <age>20</age>
 </User>
 <User>
  <name>李四</name>
  <age>21</age>
 </User>
 <User>
  <name>王五</name>
  <age>22</age>
 </User>
</Users>

/**
* 解析XML轉(zhuǎn)換成對(duì)象
*
* @param is
*      輸入流,這個(gè)就是XML文件的流
* @param clazz
*      對(duì)象Class,User類的class
* @param fields
*      字段集合一一對(duì)應(yīng)節(jié)點(diǎn)集合,例如這個(gè)類就有兩個(gè)字段,name和age,放入     List中,放入的位置要和下面的XML節(jié)點(diǎn)的位置一一對(duì)應(yīng),
List<String> fields = new ArrayList<String>();
fields.add("name");
fields.add("age");
* @param elements
*      節(jié)點(diǎn)集合一一對(duì)應(yīng)字段集合,例如這個(gè)XML有兩個(gè)屬性,name和age,放入List中,放入的位置要和上面的實(shí)體屬性的位置一一對(duì)應(yīng),
List<String> elements = new ArrayList<String>();
fields.add("name");
fields.add("age");
* @param itemElement
*      每一項(xiàng)的節(jié)點(diǎn)標(biāo)簽,在XML中按哪個(gè)節(jié)點(diǎn)當(dāng)成一組,這里是User
* @return
*/