Step 1: Write a new java class

Instead of writing the functions in 4GL, you simply need to write them in a Java class with the methods you want to use in 4GL. In our example, the two functions are buildImage and readImage. And of course, don't forget to import the necessary Java import instructions.
import com.barcodelib.barcodereader.BarcodeReader;
import com.barcodelib.barcode.Barcode;
import java.io.*;

import javax.jws.*;
import javax.jws.soap.SOAPBinding;
import javax.xml.ws.Endpoint;

public class BarcodeService {
  public byte [] buildImage(String type, String data)
  {
  /*BUILDIMAGE IMPLEMENTATION CODE DESCRIBED ABOVE*/
  }
  public String readImage(String type,byte[] img)
  { { { {
  /*READIMAGE IMPLEMENTATION CODE DESCRIBED ABOVE*/
  } }
}
If you want the service to run standalone, you must also add following the main method to tell the system the port number on which the service will run:
public static void main(String[] args)
{
  String endpointUri = "http://localhost:9090/";
  Endpoint.publish(endpointUri, new BarcodeService ());
  System.out.println("BarcodeService started at " + endpointUri);
}