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JFrame not displaying in multiple screens when we setUndecorated(true)

I am working on a use case where an undecorated JFrame needs to span across all the available displays. When i use regular JFrame with setSize i can see the JFrame stretching as per the dimensions given. The same JFrame, when we setUndecorated(true), it is not displaying.
The below code fragment is working well and displaying a JFrame across two of my monitors with 1920 x 1020 resolutions each,
JFrame myFrame=new JFrame("Welcome");
myFrame.setLocation(0, 10);
myFrame.setSize(3830,1020);
myFrame.setVisible(true);
But, when i tried to make the JFrame undecorated by adding,
myFrame.setUndecorated(true);
The frame is displaying only in the primary display and nothing is seen in my second screen.
Anyone, please help me in this regard.

How to use JFrame properly?

So I started working on a project, and after some research of JFrame, I tried this to get my window for the project:
ImageIcon hello = new ImageIcon("C:\\Users\\JP\\Desktop\\hello.jpeg");
JFrame frame = new JFrame("Test");
frame.setSize(640,480);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
frame.setBackground(Color.GREEN);
frame.setIconImage(hello.getImage());
The frame comes up in it's correct size, but does not display the icon or have the correct background color.

If you are looking to change the background of your frame, you should take a look at this Setting background color of JFrame, but either way I recommend you use the design tab of window builder, because that can make your life much easier, and such stuff can be manipulated easily. (How to open a Java form in design view?)

My Jframe form does not comes up when i try to make it responsive

i was trying to make my JFrame form responsive according to screen size but when try my code it doesnt comes up and if i remove the code it works fine.here is my code
Home frame = new Home();
Dimension screen = Toolkit.getDefaultToolkit().getScreenSize();
int i = screen.width;
int j = screen.height;
frame.setSize(i, j);
please help

To enlarge the frame to occupy the full-screen size, use:
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
To make the swing components responsive and adapting the frame size, use layout managers (e.g. FlowLayout):
A Visual Guide to Layout Managers

i got the answer. and it was really very simple i just need to put
this.setResizable(flase);
in my constructor.my coding was right

How to auto resize JFrame when elements move on next line using FlowLayout

While you resize JFrame manually via mouse, elements on JPanel can go on next line if there is no enough space, same time new element-lines can be removed if JFrame is big enough
Example:
at this moment there are two lines to fit all JButtons
If I change JFrame width via mouse, JButtons will drop on next lines:
the problem is you can't see all JButtons, JFrame needs to be resized in height.
How to make JFrame auto resize in height to fit all elements according to set width?

This is not a very good design. Show me another professional application that works like this? People don't like to see the size of frames jump. The user is usually resizing the frame to fit the app on their desktop and will get frustrated if they fix the width and the height changes. Let the user control the size.
If you want all the buttons to display, then maybe a better solution is to just make the frame non resizable by using:
frame.setResizable( false );
frame.pack();
frame.setVisible();
Anyway, if you really want to do this then you would probably add a ComponentListener to the content pane of the frame. Then in the componentResized() method you would invoke pack().
However, this will cause multiple events to be generated every couple of pixels so you may also want to use:
Toolkit.getDefaultToolkit().setDynamicLayout( false );
So that the pack() is only done once when the mouse is released.

frame.setResizable(false);
frame.pack();
frame.setVisible(true);
frame.setSize(400,200);

JFrame.setResizable(false); not working

I'm working on an online mode for a new game and in order to prevent cheating I need fix window sizes (and both players need a window with the same sizes).
I used 'jframe.setResizable(false);' but it seems to be "glitchy".
When I click the window and move it away from the border of the screen, Windows does minimize it.
Here's a video about it:
http://www.youtube.com/watch?v=AQ7OHJOuLSk&feature=youtu.be
I've tried following code in order to fix it:
Dimension d = new Dimension(width, height);
panel.getJFrame().setMaximumSize(d);
panel.getJFrame().setMinimumSize(d);
panel.setMaximumSize(d);
panel.setMinimumSize(d);
and I created a Component Listener:
if (max_height!=-1){
if (e.getComponent().getSize().getHeight()>max_height){
e.getComponent().setSize((int) e.getComponent().getSize().getWidth(),max_height);
}
}
if (max_width!=-1){
if (e.getComponent().getSize().getHeight()>max_width){
e.getComponent().setSize(max_width,(int) e.getComponent().getSize().getHeight());
}
and I tried to work with Layouts but nothing worked.
What I need now is either the possibility to prevent that minimize "glitch" (If it is a glitch) or a way to make the JPanel not resizable. Like when the size of the JFrame window is changed, the JPanel always stays the same. It's neither streched nor minimized.
Help is much appreciated :)
Sincerely Felix

So far the best patch for this annoying issue is the following. Doesn't matter where you call the setResizable(false) method. Just add this piece of code after you setVisible(true).
private void sizeBugPatch() {
while (frame.getWidth() > yourWidth) {
frame.pack();
}
}
Where yourWidth is the width you've set in any of the possible ways, either manually or by overriding setPreferredSize methods. The explanation is quite easy, frame.pack() seems to reset frame.setResizable(boolean b) somehow. You could use an if instead of the while loop but I prefer while to exclude the case the window would still be extra-sized even after a second pack().

Did you initialize the variable jframe or are you calling the general Class?
Because if you do it like this:
JFrame frame = new JFrame();
frame.setResizable(false);
It works fine for me...