Getting data from a web service from a java application

[(MC3)RaVeN]

Hi Experts.

I have been working in Java for a while now, but have never had to interact with a web service. I have built a program using the JSDK that needs to query a web service. I'm not sure where to start with this .

All i know is that I will be getting a URL that i must call and i must pass a number to this URL. I must then expect a XML document back.

I'm maybe looking for someone to tell me more or less what to expect or do .

1) How do I link to the web service from a Java application? Do i simply create a socket connection to the URL on port 80. Example http://www.dummywebservice.com?number=1000.

2) Is there any other information (http header) that must be sent?

3) Is the XML returned via the socket connection? Do i just read this in as if i was reading in a object over a socket?

4) Are there any existing simple web services that follow i can use to query try and get this working? What are they and how do I query them?

I'm really new to this and it kind of needs to be done quick. Any help would be really good. If possible demo code will help a lot.

Please help me, Thanks.

(MC3)RaVeN

[sjalle]

..but noone has complained yet, so I guess it's working

import java.net.*;
import java.io.*;
/**
 * Gets the contents of an url as a stringBuffer.
  Usage example:
try {
  URL url=new URL("http://www.whatever.com/servlets/xyz?number=1000");
  SiteConn aConnection=new SiteConn(url);
  StringBuffer sb=aConnection.getContens();
  System.out.println(sb.toString());
} catch (MalFormedURLException mfe) {
  System.err.println(mfe.getMessage());
}

 *
 */

class SiteConn {
  URL url = null;
  public SiteConn(URL url) {
    this.url = url;
  }

  public StringBuffer getContents() throws Exception {
    StringBuffer buffer;
    String line;
    int responseCode;
    HttpURLConnection connection;
    InputStream input;
    BufferedReader dataInput;
    connection = (HttpURLConnection) url.openConnection();
    responseCode = connection.getResponseCode();
    if (responseCode != HttpURLConnection.HTTP_OK) {
      throw new Exception("HTTP response code: " +
                          String.valueOf(responseCode));
    }
    try {
      buffer = new StringBuffer();
      input = connection.getInputStream();
      dataInput = new BufferedReader(new InputStreamReader(input));
      while ( (line = dataInput.readLine()) != null) {
        buffer.append(line);
        buffer.append("\r\n");
      }
      input.close();
    }
    catch (Exception ex) {
      ex.printStackTrace(System.err);
      return null;
    }
    return buffer;
  }
}

[(MC3)RaVeN]

Hi Sjalle.

Very sorry you having to hear this one again. It is sort of what i thought, but the code really helps my understanding.
Thanks a lot .

(MC3)RaVeN.