Iconifies a frame; the maximized bits are not affected. : JFrame States « Swing « Java Tutorial

1. Java Tutorial
2. Swing
3. JFrame States

import java.awt.Frame;

public class Main {
  public static void main() {

    Frame frame = new Frame();

    frame.setSize(300, 300);
    frame.setVisible(true);

    iconify(frame);
  }

  public static void iconify(Frame frame) {
    int state = frame.getExtendedState();

    // Set the iconified bit
    state |= Frame.ICONIFIED;

    // Iconify the frame
    frame.setExtendedState(state);
  }
}