Send byte array from web service to client - soap

Question

I want to send a byte array from a web service to a client that requests an operation exposed via the service. In my method, I read an image into a byte array. I think place this byte array into a wrapper POJO. This is the return type for the operation.
#Override
public ImageWrapper getImage() {
File imageFile = new File("C:\\images\\car.jpg");
ImageWrapper wrapper = null;
try {
BufferedImage img = ImageIO.read(imageFile);
ByteArrayOutputStream baos = new ByteArrayOutputStream(1000);
ImageIO.write(img, "jpg", baos);
baos.flush();
byte[] result = baos.toByteArray();
baos.close();
wrapper = new ImageWrapper();
wrapper.setContent(result);
System.out.println("Service image wrapper: " + wrapper);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return wrapper;
}
I can receive the ImageWrapper object in the client ok. It has a different id to the ImageWrapper instance that is created by the web service on the server, as I would expect. But, the problem is that when I try to get the byte[] array from the ImageWrapper, it is null... Any ideas why? The wrapper class looks like:
package soap.service.model;
public class ImageWrapper {
private byte[] content;
public void setContent(byte[] content) {
this.content = content;
}
public byte[] getImg() {
return this.content;
}
}
and the client looks like:
import java.net.MalformedURLException;
import java.net.URL;
import javax.xml.namespace.QName;
import javax.xml.ws.Service;
import soap.service.model.ImageWrapper;
import soap.service.sei.ImageSei;
public class ImageClient {
public static void main(String... args) throws MalformedURLException {
URL url = new URL("http://localhost:8080/image?wsdl");
QName qname = new QName("http://impl.service.soap/", "ImageImplService");
Service service = Service.create(url, qname);
ImageSei sei = service.getPort(ImageSei.class);
ImageWrapper iw = sei.getImage();// This is ok
System.out.println(iw.getImg()); // * This is null
}
}
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Update Even if I change the byte array in ImageWrapper to a String, it
still comes back as 'null' in the client. I have my web service set to use
'Document' style also.

Answer 1

Your interface object (the one getting serialized and being transfered) does not contain public data (only a method to get private data). Your byte[] should be a public field or property to be included in the serialized data