What is the difference?

[344a]

Hi there,
Just new to Java.

I am reading a book in which there are 2 ways to start the program.

public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable()
    {
	public void run()
	{
		JFrame frame = new TestFrame();
		...
                ...
	}
	});
}

The other way is without the EventQueue.invokeLater():

public static void main(String[] args) {
     JFrame frame = new TestFrame();
     ...
     ...
}

Tried both of them, and both of them worked.

So why should I put the EventQueue.invokeLater() in the codes? (I read the API document, but just don't really understand...)

Thx.

[GregBrannon]

The first starts the Swing application on the Event Dispatch Thread which is the correct way. The latter starts the Swing ap on the main thread which is the incorrect way. Yes, the incorrect way will work and may never present problems, but when problems do occur, they will be difficult to identify and correct, wasting a lot of unnecessary time.

Edit: I use SwingUtilities rather than EventQueue. They may be the same, but I'll have to look into it.

[copeg]

Suggested reading if you have not already: Initial Threads (The Java™ Tutorials > Creating a GUI With JFC/Swing > Concurrency in Swing)

[344a]

Thx. You guys are so helpful.