package com.tp.soft.util;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.util.ArrayList;

import java.util.List;

import java.util.Map;

import org.apache.http.HttpResponse;

import org.apache.http.HttpStatus;

import org.apache.http.NameValuePair;

import org.apache.http.client.ClientProtocolException;

import org.apache.http.client.HttpClient;

import org.apache.http.client.entity.UrlEncodedFormEntity;

import org.apache.http.client.methods.HttpPost;

import org.apache.http.impl.client.DefaultHttpClient;

import org.apache.http.message.BasicNameValuePair;

import org.apache.http.protocol.HTTP;

public class HttpUtil {

    public static String postRequest(String serverPath, Map<String, String> params, String encoding){

        List<NameValuePair> paramPair = new ArrayList<NameValuePair>();

        if(params != null && !params.isEmpty()){

            for(Map.Entry<String, String> entry : params.entrySet()){

                paramPair.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));

            }

        }

        try {

            HttpClient client = new DefaultHttpClient();

            HttpPost post = new HttpPost(serverPath);

            post.setEntity(new UrlEncodedFormEntity(paramPair, HTTP.UTF_8));

            HttpResponse response = client.execute(post);

            if(response.getStatusLine().getStatusCode() == HttpStatus.SC_OK){

                BufferedReader br = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));

                //数据

                String reqData = null;

                String responseData = "";

                while((reqData = br.readLine()) != null){

                    responseData += reqData;

                }

                br.close();

                return responseData;

            }

        } catch (ClientProtocolException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        }

        return "postRequest error";

    }

}

package com.tp.soft.app;

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.LayoutInflater;

import android.view.Menu;

import android.view.View;

import android.view.ViewGroup;

import android.widget.BaseAdapter;

import android.widget.ListView;

import android.widget.TextView;

import com.google.gson.Gson;

import com.google.gson.reflect.TypeToken;

import com.tp.soft.entity.User;

import com.tp.soft.util.HttpUtil;

public class MainActivity extends Activity {

    private ListView mListView;

    private TextView mContentTxt;

    private TextView mTimeTxt;

    private String serverPath = "http://122.226.178.54:8080/uploadApp/LoginServlet";

    private static final String ENCODING = "utf-8";

    private List<User> userList;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        loadList();

         mListView = (ListView) findViewById(R.id.list_id);

        mListView.setAdapter(new BaseAdapter() {

            @Override

            public View getView(int position, View convertView, ViewGroup parent) {

                if(null == convertView){

                    convertView = LayoutInflater.from(getApplicationContext()).inflate(R.layout.item, null);

                }

                TextView textView = (TextView) convertView.findViewById(R.id.contentTxt);

                textView.setText(userList.get(position).getUsername());

                return convertView;

            }

            @Override

            public long getItemId(int position) {

                return position;

            }

            @Override

            public Object getItem(int position) {

                return position;

            }

            @Override

            public int getCount() {

                return userList.size();

            }

        });

    }

    private List<User> loadList() {

        Map<String, String> params = new HashMap<String, String>();

        String data = HttpUtil.postRequest(serverPath, params, ENCODING);

        userList = new Gson().fromJson(data, new TypeToken<List<User>>() {}.getType());

        return userList;

    }

    @Override

    public boolean onCreateOptionsMenu(Menu menu) {

        getMenuInflater().inflate(R.menu.main, menu);

        return true;

    }

}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        response.setCharacterEncoding("utf-8");

        String uname = request.getParameter("uname");

        String pwd = request.getParameter("pwd");

        PrintWriter pw = response.getWriter();

        Gson gson = new GsonBuilder().create();

        List<User> userList = new ArrayList<User>();

        User user = new User();

        user.setUsername("zs");

        user.setPassword("");

        userList.add(user);

        User user1 = new User();

        user1.setUsername("lisi");

        user1.setPassword("");

        userList.add(user1);

        String json = gson.toJson(userList);

        pw.print(json);

    }