Creating a Borderless Window : JFrame Window « Swing « Java Tutorial

import java.awt.BorderLayout;

import javax.swing.JButton;
import javax.swing.JWindow;

public class Main {
  public static void main(String[] argv) throws Exception {
    JWindow window = new JWindow();

    JButton component = new JButton("asdf");
    // Add component to the window
    window.getContentPane().add(component, BorderLayout.CENTER);

    // Set initial size
    window.setSize(300, 300);

    // Show the window
    window.setVisible(true);

  }
}

14.80.JFrame Window
	14.80.1.	Creating a Window
	14.80.2.	Display a JFrame instance
	14.80.3.	Resizing and positioning a JFrame
	14.80.4.	Constants for JFrame window close action
	14.80.5.	Sizing Windows with Toolkit
	14.80.6.	Centering a Window
	14.80.7.	Extending JFrame: Closing Frames by Default
	14.80.8.	Exiting an Application When a JFrame Is Closed
	14.80.9.	JFrame with Label and Window Listener to Handle Closing the Frame
	14.80.10.	Handling JFrame Events
	14.80.11.	Specifying Window Decorations
	14.80.12.	Set Default window close operation
	14.80.13.	SetIconImages for JFrame
	14.80.14.	Creating a Titleless and Borderless JFrame
	14.80.15.	Close a JFrame under condition
	14.80.16.	Creating a Borderless Window
	14.80.17.	Creating Frames with a background image
	14.80.18.	Setting the Icon for a Frame
	14.80.19.	Getting All Created Frames in an Application
	14.80.20.	Removing the Title Bar of a Frame
	14.80.21.	Making a Frame Non-Resizable: use setResizable(false) to freeze a frame's size.
	14.80.22.	Use Component listener to ensure frame visibilities
	14.80.23.	Drag and move a frame from its content area
	14.80.24.	Disabling the Close Button on a JFrame
	14.80.25.	Maximize a JFrame
	14.80.26.	Make a JFrame always visible
	14.80.27.	Preventing a Window from Gaining the Focus
	14.80.28.	Getting the Child Components of a Container
	14.80.29.	Get Top Frame
	14.80.30.	Make a JInternalFrame a tool window
	14.80.31.	Move JInternalFrame To Front