如何解析android-php json web服务响应

我是android新手，学习了一点。我在android和php之间传递json对象。

我有这个代码发送json对象发送json对象到服务器。它运行得很好。它也在Toast上印刷。但是任何请帮助我如何阅读和显示从我的服务器到我的应用程序的响应?

package com.test.webservice;

import android.util.Log;
import android.view.Menu;
import android.app.Activity;
import android.os.Bundle;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import android.widget.TextView;
import android.widget.Toast;
import org.apache.http.Header;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.BasicResponseHandler;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicHeader;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.protocol.HTTP;
import org.apache.http.util.EntityUtils;
import org.json.JSONObject;
public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        String path = "http://www.mysite.com/app.php";
        HttpClient client = new DefaultHttpClient();
        HttpConnectionParams.setConnectionTimeout(client.getParams(), 10000); // Timeout
                                                                                // Limit
        HttpResponse response;
        JSONObject json = new JSONObject();
        try {
            HttpPost post = new HttpPost(path);
            json.put("service", "GOOGLE");
            json.put("name", "My Name");
            Log.i("jason Object", json.toString());
            post.setHeader("json", json.toString());
            StringEntity se = new StringEntity(json.toString());
            se.setContentEncoding((Header) new BasicHeader(HTTP.CONTENT_TYPE,
                    "application/json"));
            post.setEntity(se);
            response = client.execute(post);
            /* Checking response */
            if (response != null) {
                InputStream in = response.getEntity().getContent(); // Get the
                                                                    // data in
                                                                        // the
                                                                        // entity
                String a = convertStreamToString(in);
                Toast.makeText(getApplicationContext(), 
                        a, Toast.LENGTH_LONG).show();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }



    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
    private static String convertStreamToString(InputStream is) {
        BufferedReader reader = new BufferedReader(new InputStreamReader(is));
        StringBuilder sb = new StringBuilder();
        String line = null;
        try {
            while ((line = reader.readLine()) != null) {
                sb.append(line + "'n");
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                is.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return sb.toString();
    }
}