I cannot call a servlet from an Android application

Question

I cannot call a servlet from an Android application

This is my android app:

package org.me.sampleandroidservlet;

import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

public class MainActivity extends Activity {

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        setContentView(R.layout.main);
        TextView output=(TextView)findViewById(R.id.main_label);
        String result="";
        try
        {
            HttpClient http=new DefaultHttpClient();
            HttpGet httpget = new HttpGet(
                 "http://localhost:8084/SampleWebUser/SampleUser?hello=hi");
            HttpResponse response = http.execute(httpget);        
            result=sb.toString();
            output.setText(result);    
        }
        catch(Exception ex)
        {
            ex.printStackTrace();
        }

import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;

/**
 *
 * @author Bert Verhelst <verhelst_bert@hotmail.com>
 */
public class SampleUser extends HttpServlet {

    /**
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        out.println("<html>");
        out.println("<head>");
        out.println("<title>Servlet servlet1</title>");
        out.println("</head>");
        out.println("<body>");
        out.println("<h1>processing...</h1>");
        out.println("</body>");
        out.println("</html>");
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /**
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
        PrintWriter out = response.getWriter();
        out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 "
                + "Transitional//EN\">\n"
                + "<html>\n"
                + "<head><title>Hello WWW</title></head>\n"
                + "<body>\n"
                + "<h1>message recieved from getmethod is\n"
                + request.getParameter("hello")+"\n"
                + "</h1></body></html>");

    }

    /**
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
        PrintWriter out = response.getWriter();
        out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 "
                + "Transitional//EN\">\n"
                + "<html>\n"
                + "<head><title>Hello WWW</title></head>\n"
                + "<body>\n"
                + "<h1>dopost...</h1>\n"
                + "</body></html>");
    }

    /**
     * Returns a short description of the servlet.
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>
}

+3

android servlets

think shra1 Jan 18 '11 at 6:55

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1 answer

Vikas Patidar · Answer 1 · 2011-01-18T07:13:25+0000

Your code looks incomplete:

try this snippet:

String serverResponse =""; // it will hold the response returned by the server
try
{
    HttpClient http=new DefaultHttpClient();
    HttpGet httpget = new HttpGet(
         "http://10.0.2.2:8084/SampleWebUser/SampleUser?hello=hi");
    HttpResponse response = http.execute(httpget);        

   serverResponse = EntityUtils.toString(resEntity); // Server response
   /*
         Do your other stuff here.
   */ 
}
catch(Exception ex)
{
    ex.printStackTrace();
}

I cannot call a servlet from an Android application

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