There is a method,
public void setResizable(boolean resizable)
in the java.awt.Frame class. Whether you are extending JFrame (JFrame extends Frame) or Frame in your application, simply make the following call.
setResizable(false);
Here's an example:
public class
Test extends JFrame
{
public Test()
{
super("Test");
setResizable(false);
}
}
This call should prevent your window from being resized.