A SwingWorker that doesn't swallow exceptions

Frustrated by SwingWorker frequently swallowing very important exceptions in my code, I decided to finally try to resolve this. In summary, SwingWorker is a class that will run a task off the event dispatch thread, and then, upon completing the task, run a 'done' method on the event dispatch thread. SwingWorker also support intermediate publishing onto the EDT, etc.

The problem is, unless you call get() in the done() method, you won't know that an exception has occurred. In all of my use cases for SwingWorker, I never call get() in done(). Therefore, I was often-times missing exceptions. That is where SimpleSwingWorker comes in. I come across this code somewhere online, and genericised it to be a bit nicer to work with. Other than that, it is a drop-in replacement for the simple SwingWorker use case I tend to have.

import java.util.concurrent.ExecutionException;

import javax.swing.SwingWorker;

 * Wrap the default SwingWorker for simple cases where 
 * we are NOT returned a result in such a way
 * that exceptions are not swallowed.
public abstract class SimpleSwingWorker {

	private final SwingWorker worker = 
                new SwingWorker() {
		protected Void doInBackground() throws Exception {
			return null;

		protected void done() {
			// call get to make sure any exceptions 
			// thrown during doInBackground() are 
			// thrown again
			try {
			} catch (final InterruptedException ex) {
				throw new RuntimeException(ex);
			} catch (final ExecutionException ex) {
				throw new RuntimeException(ex.getCause());

	public SimpleSwingWorker() {}

	protected abstract Void doInBackground() throws Exception;

	protected abstract void done();

	public void execute() {

I hope that this is helpful to other people - it certainly is very useful for me!

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