New to Java

This is my requirement.

URL->
 https://test.webservices.test.com    
Module Version to hit Request XML: 
http://webservices.test.com/1ASIWPOC1A/ABCD_06_1_1A?;

Request XML:
<Security_Authenticate><user_id>XXXXX</user_id><password>XXXXXX</password> </Security_Authenticate>

This is my code

package webservice;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

import org.jdom.Element;



import com.sun.xml.internal.txw2.Document;

public class TestWebService {
	public static void main(String[] args) {
		String sRequestXML="<Security_Authenticate><user_id>XXXXX</user_id><password>XXXXXX</password> </Security_Authenticate>";
		sendAndReceiveXML(sRequestXML);
	}
private static String sendAndReceiveXML(String xmlRequest) {
		
		StringBuffer sbResponse = new StringBuffer();
		URL url = null;
		boolean debugWebSvc=true;
		
		try {
			if (debugWebSvc) 
			{
				System.out.println("Request is ------------------: ");
				System.out.println(xmlRequest);
			}

			url = new URL("http://webservices.test.com/1ASIWPOC1A/ABCD_06_1_1A");
			URLConnection conn = url.openConnection();
			conn.setRequestProperty("Content-Type", "text/xml");

			conn.setDoOutput(true);
			OutputStreamWriter wr=null;
			try {
				wr = new OutputStreamWriter(conn.getOutputStream());
			} catch (RuntimeException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			wr.write(xmlRequest);
			wr.flush();

			// Get the response
			BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
			String line;
			System.out.println("IN HERE");
			while ((line = rd.readLine()) != null) {
				
				sbResponse.append(line);
			}
			wr.close();
			rd.close();

			if (true) {
				System.out.println("Response is : ");
				System.out.println(sbResponse);
			}

		} catch (MalformedURLException e) {
			e.printStackTrace();
			sbResponse.setLength(0);
			sbResponse.append(e.getMessage());
		} catch (IOException e) {
			e.printStackTrace();
			sbResponse.setLength(0);
			sbResponse.append(e.getMessage());
		}

		return sbResponse.toString();

	}
}

O/P :
Request is ------------------: 
<Security_Authenticate><user_id>XXXXX</user_id><password>XXXXXX</password> </Security_Authenticate>
java.net.UnknownHostException: webservices.test.com
	at java.net.PlainSocketImpl.connect(Unknown Source)
	at java.net.SocksSocketImpl.connect(Unknown Source)
	at java.net.Socket.connect(Unknown Source)
	at java.net.Socket.connect(Unknown Source)
	at sun.net.NetworkClient.doConnect(Unknown Source)
	at sun.net.www.http.HttpClient.openServer(Unknown Source)
	at sun.net.www.http.HttpClient.openServer(Unknown Source)
	at sun.net.www.http.HttpClient.<init>(Unknown Source)
	at sun.net.www.http.HttpClient.New(Unknown Source)
	at sun.net.www.http.HttpClient.New(Unknown Source)
	at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(Unknown Source)
	at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Source)
	at sun.net.www.protocol.http.HttpURLConnection.connect(Unknown Source)
	at sun.net.www.protocol.http.HttpURLConnection.getOutputStream(Unknown Source)
	at webservice.TestWebService.sendAndReceiveXML(TestWebService.java:42)
	at webservice.TestWebService.main(TestWebService.java:20)

Why am i getting this exception ? I am totally new to webservices.