android--使用Struts2服务端与android交互

一，服务器端：

  首先搭建struts2的环境，导入必要的类库。

web.xml文件：

 <?xml version="1.0" encoding="UTF-8"?>
 <web-app version="2.5"
     xmlns="http://java.sun.com/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
     http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
   <welcome-file-list>
     <welcome-file>index.jsp</welcome-file>
   </welcome-file-list>
  <filter>
     <filter-name>struts2</filter-name>
     <filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>
   </filter>
   <filter-mapping>
    <filter-name>struts2</filter-name>
    <url-pattern>/*</url-pattern>
   </filter-mapping>
 </web-app>

struts.xml文件：

 <?xml version="1.0" encoding="GBK"?>
 <!DOCTYPE struts PUBLIC
         "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
         "http://struts.apache.org/dtds/struts-2.0.dtd">
 <struts>
 <package name="testjson" <span style="color:#ff0000;">extends="json-default"</span>>

     <action name="getjson" class="com.shao.action.JSONAction" method="json">
       <result type="json"></result>
     </action>

 </package>
 </struts>

Action类：

 package com.shao.action;

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

 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;

 import org.apache.struts2.interceptor.ServletRequestAware;
 import org.apache.struts2.interceptor.ServletResponseAware;

 import com.google.gson.Gson;
 import com.opensymphony.xwork2.ActionSupport;
 import com.shao.domain.Music;

 public class JSONAction extends ActionSupport implements ServletRequestAware,
         ServletResponseAware {

     /**
      *
      */
     private static final long serialVersionUID = -3604892179657815531L;
     private  HttpServletRequest request;
     private  HttpServletResponse  response;
     private  String  format;
     public String getFormat() {
         return format;
     }

     public void setFormat(String format) {
         this.format = format;
     }

     @Override
     public void setServletRequest(HttpServletRequest request) {
         // TODO Auto-generated method stub
         this.request = request;
     }

     @Override
     public void setServletResponse(HttpServletResponse response) {
         // TODO Auto-generated method stub
         this.response = response;
     }

     public  void json(){
         List<Music> list = new ArrayList<Music>();
     //  JsonArray  jsonArray = new JsonArray();
     //  JsonObject jsonObject = new JsonObject();
         Gson gson = new  Gson();
         Music m1 = new Music();
         m1.setId(1);
         m1.setAuthor("游鸿明");
         m1.setName("白色恋人");
         m1.setTime("04:01");
         list.add(m1);
         Music m2 = new Music();
         m2.setId(2);
         m2.setAuthor("陈奕迅");
         m2.setName("淘汰");
         m2.setTime("04:44");
         list.add(m2);
         Music m3 = new Music();
         m3.setId(3);
         m3.setAuthor("谢霆锋");
         m3.setName("黄种人");
         m3.setTime("04:24");
         list.add(m3);
         java.lang.reflect.Type type = new com.google.gson.reflect.TypeToken<List<Music>>() {
         }.getType();
         String beanListToJson = gson.toJson(list,type);
         System.out.println("GSON-->"+beanListToJson);
         try {
              response.setCharacterEncoding("GBK");
             //response.setContentType("text/xml;charset=utf-8");
             this.response.getWriter().write(beanListToJson);
         } catch (IOException e) {
             e.printStackTrace();
         }
     }
 }

这个Music实体类，android客户端也用到。

 package com.shao.domain;

 public class Music {

         private Integer id;
         private String name;
         private String time;
         private String  author;
         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 getTime() {
             return time;
         }
         public void setTime(String time) {
             this.time = time;
         }
         public String getAuthor() {
             return author;
         }
         public void setAuthor(String author) {
             this.author = author;
         }
 }

访问  http://localhost:8080/Client/getjson.action ;结果：

二，android客户端：

Activity类：

     

 package com.shao.main;

 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;

 import android.app.Activity;
 import android.os.Bundle;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.widget.Button;
 import android.widget.ListView;
 import android.widget.SimpleAdapter;

 public class JsonClientActivity extends Activity {
     /** Called when the activity is first created. */
     private  Button  update;
     private ListView listView;
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.main);
         update = (Button) findViewById(R.id.update);
         listView = (ListView) findViewById(R.id.list);
         update.setOnClickListener(new OnClickListener() {

             @Override
             public void onClick(View v) {
                 // TODO Auto-generated method stub
                  String urlStr="http://10.0.2.2:8080/Client/getjson.action";
               String    result  = GsonUtil.getJson(urlStr);
               List<Music>  list = GsonUtil.getListFromJson(result);
               List<Map<String,Object>>  data  = getAdapterData(list);

              SimpleAdapter  adapter  =new  SimpleAdapter(JsonClientActivity.this, data, R.layout.list, new String[]{"name","author","time"}, new int[]{R.id.name,R.id.author,R.id.time});
              listView.setAdapter(adapter);
              //listView.
             }
         });
     }
     private List<Map<String,Object>>  getAdapterData(List  list){
           List<Map<String,Object>>  data = new  ArrayList<Map<String,Object>>();
           for(int i=0;i<list.size();i++){
               Map<String,Object>  map = new HashMap<String, Object>();
               Music music= (Music)list.get(i);
               map.put("name",music.getName());
               map.put("author", music.getAuthor());
               map.put("time",music.getTime());
               data.add(map);
           }
           return   data;
     }
 }

 package com.shao.main;

 import java.net.URI;
 import java.util.List;

 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.client.HttpClient;
 import org.apache.http.client.methods.HttpPost;
 import org.apache.http.impl.client.DefaultHttpClient;
 import org.apache.http.util.EntityUtils;

 import com.google.gson.Gson;

 public class GsonUtil {
        public static  String getJson(String  url){

            HttpClient client = new DefaultHttpClient();

            HttpPost  request;
            try {
             request = new HttpPost(new URI(url));
             HttpResponse  response  =  client.execute(request);
               // 判断请求是否成功
             if (response.getStatusLine().getStatusCode() == 200) { //200表示请求成功
                 HttpEntity  entity = response.getEntity();
                 if(entity!=null){
                     String beanListToJson = EntityUtils.toString(entity,"GBK");
                     return beanListToJson;
                 }
             }

         } catch (Exception e) {
             // TODO: handle exception
         }
          return  null;
        }
    public  static  List<Music>  getListFromJson(String json){
         java.lang.reflect.Type type = new com.google.gson.reflect.TypeToken<List<Music>>() {
         }.getType();
         Gson gson = new Gson();
         List<Music>  list  = gson.fromJson(json, type);
         return list;
    }
 }

list.xml

 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:orientation="vertical"
     android:layout_width="fill_parent"
     android:layout_height="fill_parent"
     >
 <TextView
     android:id="@+id/name"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:text="name"
     />
  <TextView
     android:id="@+id/author"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:layout_below="@id/name"
     android:paddingTop="5px"
     android:text="author"
      >
  </TextView>
  <TextView
     android:id="@+id/time"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:layout_below="@id/name"
     android:layout_alignTop="@id/author"
     android:layout_alignParentRight="true"
     android:text="time">
  </TextView>
 </RelativeLayout>

运行结果：

主要的交互都是通过goolge的Gson完成