Java Code:
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.CLabel;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

public class CLabelGradientBG {
  Display display = new Display();
  Shell shell = new Shell(display);
  Image image = new Image(display, "java2s.gif");

  public CLabelGradientBG() {
    init();

    CLabel labelGradientBg = new CLabel(shell, SWT.SHADOW_IN);
    labelGradientBg.setText("CLabel with gradient colored background");
    labelGradientBg.setImage(image);
    labelGradientBg.setBounds(10, 10, 300, 100);
    labelGradientBg.setBackground(
      new Color[] {
        display.getSystemColor(SWT.COLOR_GREEN),
        display.getSystemColor(SWT.COLOR_WHITE),
        display.getSystemColor(SWT.COLOR_RED)},
      new int[] { 50, 100 });

    shell.pack();
    shell.open();
    //textUser.forceFocus();

    // Set up the event loop.
    while (!shell.isDisposed()) {
      if (!display.readAndDispatch()) {
        // If no more entries in event queue
        display.sleep();
      }
    }

    display.dispose();
  }

  private void init() {

  }

  public static void main(String[] args) {
    new CLabelGradientBG();
  }
}