9 replies to this topic

[Mozana]

What up guys, wim pls xplains this to me.
What is the effect of doing this:

Thread ScreenThread = new  {

  @Override

 public void run() {

  //maybe in here I call nethods to build up panels

 }

};

            ScreenThread.start();

what i wana understand is this thread, will it affect the mian thread in any way?
ok other guys can help too

[Norm]

Does that code compile?

If you start a new thread, then it will compete with the main thread for cpu cycles depending on how many cores your computer has.

[gregwarner]

What do you mean by, "will it affect the main thread?"

In short, your example above won't affect the main thread at all. But that's just because you haven't written anything in there to cause it to do so.

However, you can, if you wish, have threads branch off of the main thread and then report back to the main thread of progress, results, exceptions, using notify(), Future, etc. It just depends on what you want your worker thread to do.

Now, I did notice you said something in your example of using the thread to build up panels. Are you trying to create GUI controls in this thread? If so, use SwingUtilities.invokeLater() to create your GUI controls on the Event Dispatch Thread. The reason for this is because Java expects you to do all Swing work in the Event Dispatch Thread. Here's an example of a generally accepted good practice for affecting your Swing controls from the EDT:

SwingUtilities.invokeLater(new Runnable() {

    @Override

    public void run() {

        JPanel panel = new JPanel();

        // initialize panel here.

        container.add(panel); // where 'container' is some Swing Container that you're adding panel to.

    }

});

[Mozana]

well what i wanted to make clear in the section of build was just to mention the fact that the thread will run for sum tym, what i mean by affect the main thread i meant that will the main thread wait for this one to finish before it continues? or the main thread will start this one then continue with its duties?
but in essence what I want to do is create a program that downloads stuff from the internet but do so quickly(of cause the internet speed is a factor but nevermind that), so the thread must start the download while the main thread does sum else, sorry for the essay

[Norm]

When you have more than one thread in a program, the OS determines how much time each of the threads gets to execute. Whether one thread impacts the other will depend on the number of cores in your computer and how much processing time each thread uses.

[Mozana]

So will this approach yield the expected results, like make d application run faster?

[Norm]

It depends on your computer and the OS. What multiple threads will do is prevent the blocking of one thread while it is waiting for input from causing another thread to wait. The code won't run any faster.

[Mozana]

ok thanks

[lethalwire]

Mozana said:

So will this approach yield the expected results, like make d application run faster?

Be sure to check this link out:
multithreading - Java - multithreaded code does not run faster on more cores - Stack Overflow

You can't assume your program will be any faster with an increase in threads. There are several other factors that need to be accounted for.

[Mozana]

so how do i make it faster, what are the other factors?
K so i checked that link out, thanks they offer some good explanations, but i am not sure if its something i can use now,
Thanks nevertheless