Java Code:
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;

public class Snippet168 {

  public static void main(String[] args) {
    final Display display = new Display();
    Shell shell = new Shell(display);
    shell.addListener(SWT.Paint, new Listener() {
      public void handleEvent(Event event) {
        int x = 20, y = 20, w = 120, h = 60;
        GC gc = event.gc;
        gc.setForeground(display.getSystemColor(SWT.COLOR_BLUE));
        gc.setLineWidth(10);
        int[] caps = { SWT.CAP_FLAT, SWT.CAP_ROUND, SWT.CAP_SQUARE };
        for (int i = 0; i < caps.length; i++) {
          gc.setLineCap(caps[i]);
          gc.drawLine(x, y, x + w, y);
          y += 20;
        }
        int[] joins = { SWT.JOIN_BEVEL, SWT.JOIN_MITER, SWT.JOIN_ROUND };
        for (int i = 0; i < joins.length; i++) {
          gc.setLineJoin(joins[i]);
          gc
              .drawPolygon(new int[] { x, y, x + w / 2, y + h,
                  x + w, y });
          y += h + 20;
        }
      }
    });
    shell.open();
    while (!shell.isDisposed()) {
      if (!display.readAndDispatch())
        display.sleep();
    }
  }
}