Setting size of inner region of Java SWT shell window

Question

In a Java SWT shell window, how do I set its inner size than its whole window frame size?

For instance, if I use shell.setSize(300, 250) this would make the whole window

Answer 1

import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.widgets.*;

public class SWTClientAreaTest
{
    Display display;
    Shell shell;
    final int DESIRED_CLIENT_AREA_WIDTH = 300;
    final int DESIRED_CLIENT_AREA_HEIGHT = 200;

    void render()
    {
        display = Display.getDefault();
        shell = new Shell(display, SWT.SHELL_TRIM | SWT.CENTER);

        Point shell_size = shell.getSize();
        Rectangle client_area = shell.getClientArea();

        shell.setSize
        (
            DESIRED_CLIENT_AREA_WIDTH + shell_size.x - client_area.width,
            DESIRED_CLIENT_AREA_HEIGHT + shell_size.y - client_area.height
        );

        shell.open();

        while (!shell.isDisposed()) 
        {
            if (!display.readAndDispatch()) 
            {
                display.sleep();
            }
        }

        display.dispose();
    }

    public static void main(String[] args)
    {
        SWTClientAreaTest appl = new SWTClientAreaTest();
        appl.render();
    }
}