If you have a number of image resource methods, it is well worth creating a MessageBodyWriter to output the BufferedImage:
@Produces({ "image/png", "image/jpg" })
@Provider
public class BufferedImageBodyWriter implements MessageBodyWriter<BufferedImage> {
@Override
public boolean isWriteable(Class<?> type, Type type1, Annotation[] antns, MediaType mt) {
return type == BufferedImage.class;
}
@Override
public long getSize(BufferedImage t, Class<?> type, Type type1, Annotation[] antns, MediaType mt) {
return -1; // not used in JAX-RS 2
}
@Override
public void writeTo(BufferedImage image, Class<?> type, Type type1, Annotation[] antns, MediaType mt, MultivaluedMap<String, Object> mm, OutputStream out) throws IOException, WebApplicationException {
ImageIO.write(image, mt.getSubtype(), out);
}
}
This MessageBodyWriter will be used automatically if auto-discovery is enabled for Jersey, otherwise it needs to be returned by a custom Application sub-class. See JAX-RS Entity Providers for more info.
Once this is set up, simply return a BufferedImage from a resource method and it will be be output as image file data:
@Path("/whatever")
@Produces({"image/png", "image/jpg"})
public Response getFullImage(...) {
BufferedImage image = ...;
return Response.ok(image).build();
}
A couple of advantages to this approach: