JSON Tutorial

In this tutorial, I will show you how to pass and retrieve data on a webservice. Here's the sample code below. Create Activity and named it Sample.java.

package.com.your_package

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.text.DecimalFormat;

import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONException;
import org.json.JSONObject;

public class Sample {
public final static String ServerIP = "192.168.13.249";
public final static String URL = "http://192.168.13.249/developer/Mobile/1.0/sample/sample.asmx/sample";
 
public Sample() 
{ }

//This part is receiving a data to pass in a web service

private JSONObject sendJsonRequest(String host, int port,String uri, JSONObject param) 
           throws ClientProtocolException, IOException, JSONException
{
   HttpClient httpClient = new DefaultHttpClient();
   HttpHost httpHost = new HttpHost(host, port);   
   HttpPost httpPost = new HttpPost(uri);
         //To make sure that data pass converted to json object.
   httpPost.addHeader("Content-Type", "application/json; charset=utf-8");


if (param != null)
{
   HttpEntity bodyEntity = new StringEntity(param.toString(), "utf8");
   httpPost.setEntity(bodyEntity);
}


HttpResponse response = httpClient.execute(httpHost, httpPost);
HttpEntity entity = response.getEntity();


String result = null;
if (entity != null) {
   InputStream instream = entity.getContent();
   BufferedReader reader = new BufferedReader(
        new InputStreamReader(instream));
   StringBuilder sb = new StringBuilder();


   String line = null;
   while ((line = reader.readLine()) != null)
       sb.append(line + "\n");


   result = sb.toString();
   instream.close();           
}


httpPost.abort();
return result != null ? new JSONObject(result) : null;


}

//Create a json object of your data input because the webservice needs a json object to pass.

public JSONObject Sample(String your_field1  String your_field2  String your_field3  String your_field4  String your_field5, String your_field6, String your_field7) throws Exception {
JSONObject result = null;
try
{
   JSONObject param = new JSONObject();
   param.put("samekey_api1", your_field1);
   param.put("samekey_api2", your_field2);
   param.put("samekey_api3", your_field3);
   param.put("samekey_api4", your_field4);
   param.put("samekey_api5", your_field5);
   param.put("samekey_api6", your_field6);
   param.put("samekey_api7", your_field7);


   result = sendJsonRequest(ServerIP, 80, URL, param);
   /*if (result == null)
   {
      result = "null";
   }*/
}
catch (Exception ex)
{
ex.printStackTrace();
}
return result;

}
}


And in your MainActivity.java. Simple call this code below.

//instantiating the function
SendoutMobile ws = new SendoutMobile();
resp= ws.SendoutMobile(your_field1, your_field2  your_field3  your_field4  your_field5  your_field6  text4.getText().toString().replaceAll(",",""));

//to retrieve the data example        
String repscode = resp.getString("respcode");