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HTTP Request Returns and Parses JSON Data

/*   Note the difference in sending GET and POST requests * 1. Create an HttpGet (or HttpPost) object, passing the URL to be requested into the HttpGet (or HttpPost) object via its constructor;   2. Use the execute method of the DefaultHttpClient class to send an HTTP GET or HTTP POST request and return an HttpResponse object;   3. Retrieve the response information via the getEntity method of the HttpResponse interface. * */ public class TestHttpActivity extends Activity {  private Button btn_get;  private Button btn_post;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        btn_get=(Button)findViewById(R.id.btn_get);        btn_post=(Button)findViewById(R.id.btn_post);        btn_get.setOnClickListener(listener);        btn_post.setOnClickListener(listener);    }    private OnClickListener listener=new OnClickListener() {				@Override		public void onClick(View v) {			switch (v.getId()) {			case R.id.btn_post:				Log.i("TestHttpActivity", "ok");				 DefaultHttpClient client = new DefaultHttpClient(); 				 /**NameValuePair is a request parameter sent to the server    param.get("name") **/                 List<NameValuePair> list = new ArrayList<NameValuePair>();                   NameValuePair pair1 = new BasicNameValuePair("name", "name0001");                   NameValuePair pair2 = new BasicNameValuePair("age", "age0001");                   list.add(pair1);                   list.add(pair2);                   UrlEncodedFormEntity entity=null;				try {					/**Set encoding **/					entity = new UrlEncodedFormEntity(list,"UTF-8");				} catch (UnsupportedEncodingException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}  				/**Create a new POST request**/                 HttpPost post = new HttpPost("http://aaron-pc.wsd.com/Test/testHttp");                   post.setEntity(entity);                   HttpResponse response=null;                 String strResult="";				try {					/**Client sends request to server**/					response = client.execute(post);				} catch (ClientProtocolException e) {					// TODO Auto-generated catch block					e.printStackTrace();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}                     /**Request sent successfully, and response received**/                 if(response.getStatusLine().getStatusCode()==200){  					try {						  /**Read the JSON string data returned by the server**/						   strResult = EntityUtils.toString(response.getEntity());   					} catch (IllegalStateException e) {						// TODO Auto-generated catch block						e.printStackTrace();					} catch (IOException e) {						// TODO Auto-generated catch block						e.printStackTrace();					}													 JSONObject jsonObject = null;					try {						/**Convert JSON string to JSON object**/						jsonObject = getJSON(strResult);					} catch (JSONException e1) {						// TODO Auto-generated catch block						e1.printStackTrace();					}					 String names="";					                     try {                    	 /**                    	  * jsonObject.getString("code") retrieves the code                    	  * For example, the JSON string returned here is [code:0,msg:"ok",data:[list:{"name":1},{"name":2}]]                    	  * **/                    	                     	 /**Get the 'data' key**/                    	 String data=jsonObject.getString("data");                    	 /**Convert the data under 'data' to a JSON object**/                    	 JSONObject jDat = new JSONObject(data);                    	 /**Check if 'list' exists under the 'data' object**/                    	 if(jDat.get("list")!=null){                    		 /**Convert 'list' to a JSONArray object**/                    		 JSONArray jarr = jDat.getJSONArray("list");                    		 /**Iterate through the 'list' object**/                    	 for (int i = 0; i < jarr.length(); i++) {                    		                     		 /** **/                    		 JSONObject jsono = (JSONObject) jarr.get(i);                     		                     		 /**Retrieve the 'name' value under 'list' **/                    		 names=names+jsono.getString("name");                    		          				}                    	 }						Toast.makeText(TestHttpActivity.this, "code:"+jsonObject.getString("code")+"name:"+names, Toast.LENGTH_SHORT).show();					} catch (JSONException e) {						// TODO Auto-generated catch block						e.printStackTrace();					}                                                                 }                   else Toast.makeText(TestHttpActivity.this, "POST submission failed", Toast.LENGTH_SHORT).show();  				break; 			case R.id.btn_get:				 DefaultHttpClient client1 = new DefaultHttpClient(); 				 /**NameValuePair is a request parameter sent to the server    param.get("name") **/                                UrlEncodedFormEntity entity1=null;			 				/**Create a new GET request**/                 HttpGet get = new HttpGet("http://aaron-pc.wsd.com/Test/testHttp");                   HttpResponse response1=null;                 String strResult1="";				try {					/**Client sends request to server**/					response1 = client1.execute(get);				} catch (ClientProtocolException e) {					// TODO Auto-generated catch block					e.printStackTrace();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}                     /**Request sent successfully, and response received**/                 if(response1.getStatusLine().getStatusCode()==200){  					try {						  /**Read the JSON string data returned by the server**/						   strResult1 = EntityUtils.toString(response1.getEntity());   					} catch (IllegalStateException e) {						// TODO Auto-generated catch block						e.printStackTrace();					} catch (IOException e) {						// TODO Auto-generated catch block						e.printStackTrace();					}													 JSONObject jsonObject1 = null;					try {						/**Convert JSON string to JSON object**/						jsonObject1 = getJSON(strResult1);					} catch (JSONException e1) {						// TODO Auto-generated catch block						e1.printStackTrace();					}					 String names="";					                     try {                    	 /**                    	  * jsonObject.getString("code") retrieves the code                    	  * For example, the JSON string returned here is [code:0,msg:"ok",data:[list:{"name":1},{"name":2}]]                    	  * **/                    	                     	 /**Get the 'data' key**/                    	 String data=jsonObject1.getString("data");                    	 /**Convert the data under 'data' to a JSON object**/                    	 JSONObject jDat1 = new JSONObject(data);                    	 /**Check if 'list' exists under the 'data' object**/                    	 if(jDat1.get("list")!=null){                    		 /**Convert 'list' to a JSONArray object**/                    		 JSONArray jarr1 = jDat1.getJSONArray("list");                    		 /**Iterate through the 'list' object**/                    	 for (int i = 0; i < jarr1.length(); i++) {                    		                     		 /** **/                    		 JSONObject jsono = (JSONObject) jarr1.get(i);                     		                     		 /**Retrieve the 'name' value under 'list' **/                    		 names=names+jsono.getString("name");                    		          				}                    	 }						Toast.makeText(TestHttpActivity.this,  "GET request: code:"+jsonObject1.getString("code")+"name:"+names, Toast.LENGTH_SHORT).show();					} catch (JSONException e) {						// TODO Auto-generated catch block						e.printStackTrace();					}                                                                 }                   else Toast.makeText(TestHttpActivity.this, "GET submission failed", Toast.LENGTH_SHORT).show();  				break;			}					}	};	public JSONObject getJSON(String sb) throws JSONException {          return new JSONObject(sb);      }  }