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Netbean GUI interface window closing

I'm working in the netbeans GUI interface, and I want to know how to close the window. I found the following code:
frame.dispatchEvent(new WindowEvent(frame, WindowEvent.WINDOW_CLOSING));
However, I cannot find the name of the frame in the code.
How do I find the frame name, or am I going about this the wrong way? How do I close it?

Put this line in your form no need to use window event
setDefaultCloseOperation(EXIT_ON_CLOSE);

How do I close it?
When you create the frame you need code like:
Jframe frame = new JFrame(...);
frame.setDefaultCloseOperation(JFrame.EXIT__ON_CLOSE);
Now when you click on the "close" button the application will exit.
However you may also want to close the frame by using a menu item. In this case what you want to do is create an Action that you can add to your "Exit" JMenuItem.
Check out the Exit Action found in Closing an Application. The Exit Action shows how you can access the current frame in order to dispatch the windowClosing() event to the frame. So the "Exit" menu item will then function just like the user clicking on the "close" button.

You are using NetBeans IDE, go to JFrame Properties, the very first option is DefaultCloseOperation, use the drop down menu to toggle between options available or you can add custom codes.

Found an answer at https://netbeans.org/kb/articles/gui-functionality.html
Turns out all I needed was
System.exit(0);

Focussing in Java swing

I'm developing an application using java swing. When I click a button, I want another window to be opened. This works fine. But it is possible to alt+tab to the original window and then interact with it even after the new window is open. Is there any way not to let the user focus the original window after the new window appears? By window I'm referring to Jframe/Jdialog.

Assuming the instance of your main JFrame window is called mainWindow:, the following code will prevent switching the focus.
// the second parameter makes the dialog modal and will prevent
// switching the focus to the mainWindow
JDialog dialog = new JDialog(mainWindow, true);
...
dialog.setVisible(true);
Documentation on JDialog: http://docs.oracle.com/javase/6/docs/api/javax/swing/JDialog.html

You may try to use a JDialog instead of JFrame and pass the instance of JFrame to JDialog constructor
You may also try to check
frame.setAlwaysOnTop(true);
or may be like this:-
frame.toFront();
frame.setState(Frame.NORMAL);

Exiting out of one of two JFrame exits out of both

I have two seperate JFrames but when i click the X in the topright of one, it will exit out of the other also. I have an "exit" button near the bottom to do setVisible(false), but i still have the tendency to use the x button. How would i make it so that it doesnt cancel out of the entire project?
Also, how would i make it so that the second JFrame locks out of the other JFrame untill the second JFrame is closed, like how a popup message works

Don't give your GUI two JFrames. The GUI ideally should have only one GUI. If a separate window is required, then make it a dialog such as a JDialog, and this won't happen.
Also, how would i make it so that the second JFrame locks out of the other JFrame untill the second JFrame is closed, like how a popup message works
You are perfectly describing the behavior of a modal JDialog or JOptionPane. Just use 'em.
Later we'll chat about using CardLayouts to swap views in a single GUI.
Edit, you state:
Im using Netbeans form editor to create them faster but I only see JFrame and JPanel. Can I edit them in Netbeans? I'd rather not do them through scratch Java
You've touched on another zealous belief of mine, that this is yet another reason not to use a code generator when learning a library as one can get too tied into the code generator, that it prevents one from learning the library. I strongly advise you to put aside your code-generation tool and create by hand, referring to the tutorials and API. Then later when you get more familiar with the library, sure use the tool. By the way, an answer to your direct question here is to gear your GUI's to create JPanels, and then use these JPanels where and how you want them -- in JFrames, or JDialogs, or JOptionPanes, or swapped in CardLayouts, or JTabbedPanes or nested in other JPanels,... etc...

You should be using a modal JDialog, not a second JFrame, because JDialogs provide certain functionality such as not adding another window bar to the taskbar, and automatically setting focus when the parent JFrame receives focus. Modal JDialogs prevent user input to the JFrame while it's open, useful for an "Are you sure you want to exit?" dialog, for example.
As for one JFrame exiting the other, you probably have their default close operation set to EXIT_ON_CLOSE. If you do this:
jframe.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
jframe.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent we){
handleUserWantsToCloseWindow();
}
});
Then you can control what happens when the user wants to close, such as popping up a "Save Changes?" modal JDialog or "Are you sure you want to quit?" modal JDialog. Note that you have to manually dispose of the JFrame if you use this method.

How to properly hide a JFrame

I have a very simple JFrame window that contains one button: No.
In the main function I set setVisible(true); my JFrame and in the No button listener I want to close the window so I set the visibility to false: setVisible(false); and after that I do System.exit(0); in order to prevent possible memory leaks when running the program many times.
I have two questions:
Do I really need to System.exit(0); in the above case?
If I have this JFrame as a popup window, I can't really use System.exit(0); because this will terminate the whole program. So how can I properly close the popup window and stay in the main JFrame window? (Now I close it only by setVisible(false); and when I do it several times through the program execution, the program turns very slow).

use CardLayout
if is there real reason for another popup container
use JDialog with parent to JFrame, with setModal / ModalityTypes
create only one JDialog and to reuse this one JDialog by getContentPane#removeAll()
use JOptionPane for simple users interaction
put both together, above two points, to use CardLayout for popup JDialog with parent to JFrame, notice after switch from one card to another could be / is required to call JDialog.pack()

setVisible will cause slowdown
dispose will cause slowdown
System.exit will close entire JVM
Therefore, you should reuse a single JFrame or JDialog.
In the button's ActionListener, invoke frame.setVisible(false);. Then instead of creating a new frame just do frame.setVisible(true);. If you want to change the contents of the frame, there is the function frame.getContentPane().removeAll();.

Just add this: JFrame.setDefaultCloseOperation(DISPOSE_ON_CLOSE).
Note: The default option for JFrame is HIDE_ON_CLOSE.

You can use the dispose() method of the JFrame class to close the frame and release all resources associated with it, including its child components.

how do i close a frame yet open a new frame?

how do i close a frame yet open a new frame?
i have a frame, (help)
when i click on my menu item
i want to open (mainForm)
exit from help.
new mainForm().setVisible(true);
System.exit(0);
i know this closes the whole program however how do i get it to only close the current frame
thanks

If you no longer want to use the frame you could use frame.dispose()
If you just want to hide it use frame.setVisible(false).
If you extended a Frame and are trying to close it from within use this.dispose or this.setVisible(false).

You should rethink your requirments. For the user, it would be best to have both the program and the help window visible at the same time. Closing the main window when showing the help screen and vice versa is really, really bad for usability - you shouldn't do it. We've had window-based GUIs for almost 30 years now - showing several windows on screen at the same time is what they're for!

Let's say you created your frame as so:
JFrame mainframe = new JFrame("Radio Notes");
//show Frame
mainframe.setVisible(true);
//close the frame
mainframe.dispose();

I think you should hide the frame you do not wish shown with setVisible(false). System.exit(0) stops the JVM ending the entire program.
In short, the semantics of setVisible has nothing to do with starting / stopping the application.
If you want to start an entire new application you'd have to look at Runtime.exec(). I don't really know if you can close the parent process (the Help application) with exit() though.

try setting the default close operation for the JFrame like so.
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
Then implement a WindowListener that performs the actions you want when a window closing event is fired.