Android: Facing problem -BasicNetwork.performRequest: Unexpected response code 500 '

I am trying to send data from Android application to Servlet. Android app is working correctly.

The problem is only related to the request sent to the Servlet. It gives error BasicNetwork.performRequest: Unexpected response code 500

Note. I am using Android Volley library to send my request to a servlet.

Below I have mentioned: 1. My Android Application Code 2. My Servlet Code 3. LogCat

My Android app: MainActivity.java file

            package com.example.hawk;

            import java.util.HashMap;
            import java.util.Map;

            import com.android.volley.AuthFailureError;
            import com.android.volley.Request;
            import com.android.volley.RequestQueue;
            import com.android.volley.Response;
            import com.android.volley.toolbox.StringRequest;
            import com.android.volley.toolbox.Volley;

            import android.support.v7.app.ActionBarActivity;
            import android.app.Activity;
            import android.os.Bundle;
            import android.view.Menu;
            import android.view.MenuItem;
            import android.view.View;
            import android.view.View.OnClickListener;
            import android.widget.Button;
            import android.widget.EditText;

            public class MainActivity extends Activity implements View.OnClickListener {

            EditText var_sp = null;
            EditText var_ect = null;
            EditText var_er = null;
            EditText var_iat = null;
            EditText var_atp = null;
            Button submit;
            RequestQueue rq = null;

            @Override
            protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            v1 = (EditText) findViewById(R.id.sp);
            v2 = (EditText) findViewById(R.id.ect);
            v3 = (EditText) findViewById(R.id.er);
            v4 = (EditText) findViewById(R.id.iat);
            v5 = (EditText) findViewById(R.id.atp);
            submit = (Button) findViewById(R.id.submit);        
            rq=Volley.newRequestQueue(this);
            submit.setOnClickListener(this);
            }
            @Override
            public boolean onCreateOptionsMenu(Menu menu) {
            // Inflate the menu; this adds items to the action bar if it is present.
            getMenuInflater().inflate(R.menu.main, menu);
            return true;
            }

            @Override
            public boolean onOptionsItemSelected(MenuItem item) {
            // Handle action bar item clicks here. The action bar will
            // automatically handle clicks on the Home/Up button, so long
            // as you specify a parent activity in AndroidManifest.xml.
            int id = item.getItemId();
            if (id == R.id.action_settings) {
            return true;
            }
            return super.onOptionsItemSelected(item);
            }

            @Override
            public void onClick(View v) {
            switch (v.getId()) {
            case R.id.submit:

            new Thread(new Runnable() {
            public void run() {
            try{
            StringRequest postReq = new StringRequest(Request.Method.POST, "http://192.168.0.103:8080/ServletABC",new Response.Listener<String>() {
            protected Map<String, String> getParams() throws AuthFailureError {
                Map<String, String> params = new HashMap<String, String>();
                params.put("var1",v1.getText().toString());
                params.put("var2",v2.getText().toString());
                params.put("var3",v3.getText().toString());
                params.put("var4",v4.getText().toString());
                params.put("var5",v5.getText().toString());
                return params;
            }

            @Override
            public void onResponse(String response) {
                // TODO Auto-generated method stub

            }

            }, null);

            rq.add(postReq);
            }catch(Exception e)
            {
            e.printStackTrace();
            }

            }
            }).start();

            break;


            }
            }
            }

      

        
        
        
      

    

My servlet:

            import java.io.*;
            import java.util.*;
            import javax.servlet.*;
            import javax.servlet.http.*;
            import java.sql.*;

            public class OBD_Feeder extends HttpServlet{
                 // JDBC driver name and database URL 
                 public static final String JDBC_DRIVER="com.mysql.jdbc.Driver";
                 public static final String DB_URL="jdbc:mysql://localhost/Test";
                 // Database credentials 
                 public static final String USER ="xxxx";
                 public static final String PASS ="xxxx";
                 Connection conn;
                 Statement stmt;

                 public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException,IOException
                {       
                    response.setContentType("text/html");
                    PrintWriter out = response.getWriter();
                    double v1=Double.parseDouble(request.getParameter("var1")); 
                    double v2=Double.parseDouble(request.getParameter("var2"));
                    double v3=Double.parseDouble(request.getParameter("var3"));
                    double v4=Double.parseDouble(request.getParameter("var4"));
double v5=Double.parseDouble(request.getParameter("var5"));
                    Calendar calendar = Calendar.getInstance();
                java.sql.Timestamp today_ts = new java.sql.Timestamp(calendar.getTime().getTime());

            //System.out.println("TimeStamp: "+today_ts);

                try{     
                 // Register JDBC driver 
                     Class.forName("com.mysql.jdbc.Driver");
                     // Open a connection 
                     conn =DriverManager.getConnection(DB_URL,USER,PASS);

                     // Execute SQL query 
                     stmt = conn.createStatement();
                     PreparedStatement pst =(PreparedStatement) conn.prepareStatement("insert into obd_test1(speed,coolant_temp,engine_rpm,in_air_temp,throttle_position, time_stamp) values(?,?,?,?,?,?)");

                  pst.setDouble(1,v1);  
                  pst.setDouble(2,v2);        
                  pst.setDouble(3,v3);
                  pst.setDouble(4,v4);
                  pst.setDouble(5,v5);
                  pst.setTimestamp(6,today_ts);
                  System.out.println("DB Query: "+pst.toString());
                  //Query execution
                  int i = pst.executeUpdate();
                  //conn.commit(); 
                  String msg=" ";
                  if(i!=0){msg="Record has been inserted";}  
                  else{msg="failed to insert the data";}
                  System.out.println("DB Transaction Status: "+msg);
                String docType ="<!doctype html public \"-//w3c//dtd html 4.0 "+"transitional//en\">\n";
                out.println(docType +
                "<html>\n"+
                "<head><title>OBD Feeder</title></head>\n"+
                "<body bgcolor=\"#f0f0f0\">\n"+
                "<h1 align=\"center\">DATA Received:</h1>\n"+
                "<ul>\n"+msg+"</ul>\n"+
                "</body></html>");

                  pst.close();
                stmt.close();
                conn.close();
                 }catch(SQLException se){ se.printStackTrace();}//Handle errors for JDBC se.printStackTrace();
                 catch(Exception e){ e.printStackTrace();}//Handle errors for Class.forName e.printStackTrace();
                 finally
                 { //finally block used to close resources 
                    try{ 
                        if(stmt!=null) 
                        stmt.close();
                    }catch(SQLException se2){ se2.printStackTrace();}// nothing we can do 
                    try{ 
                            if(conn!=null) 
                            conn.close();
                        }catch(SQLException se){ se.printStackTrace();
                        }//end finally try 
                     }      
                }   
            }

      

        
        
        
      

    

My LogCat:

            08-15 10:42:55.128: I/HAWK(29403): POST Request: [ ] http://192.168.0.102:8080/OBD_Feeder 0x85adf656 NORMAL 3
            08-15 10:42:55.408: E/Volley(29403): [1056] BasicNetwork.performRequest: Unexpected response code 500 for http://192.168.0.102:8080/ServletABC
            08-15 10:42:55.408: D/HAWK(29403): Error: null
            08-15 10:44:56.648: W/IInputConnectionWrapper(29403): getTextBeforeCursor on inactive InputConnection