import javax.swing.JPanel;
import javax.swing.SwingWorker;


public abstract class SortThread<T extends Comparable<T>> extends SwingWorker<Void, Void> {
    protected T[] array;
    protected JPanel view;
    protected final int delay;

    protected void repaintDelay()
    {
        view.repaint();
        try {
            Thread.sleep(delay);
        } catch (InterruptedException e) {
            return;
        }
    }

    public SortThread(T[] array, JPanel view, int delay)
    {
        this.array = array;
        this.view = view;
        this.delay = delay;
    }
}

//EXAMPLE:

import javax.swing.JPanel;

public class BubbleSortThread<T extends Comparable<T>> extends SortThread<T> {

    public BubbleSortThread(T[] array, JPanel view, int delay) {
        super(array, view, delay);
    }

    private void bubbleSort(T[] a, BubbleSortThread<T> parent) {
        for (int j = 0; j < a.length; j++) {
            boolean sorted = true;

            // Elements beyond length - (j + 1) are sorted, so don't check them
            for (int i = 0; i < a.length - (j + 1) && !parent.isCancelled(); i++) {
                if (a[i].compareTo(a[i + 1]) > 0) {
                    T temp = a[i];
                    a[i] = a[i + 1];
                    a[i + 1] = temp;
                    sorted = false;
                }
                repaintDelay();
            }

            // Stop if the array is sorted
            if (sorted || parent.isCancelled())
                break;
        }
    }

    @Override
    protected Void doInBackground() throws Exception {
        bubbleSort(array, this);
        view.repaint();
        return null;
    }

}