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Thread: I'm vary new to java programming and confused about som concepts.

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    Default I'm vary new to java programming and confused about som concepts.

    To create threading there is an object

    Thread.sleep();

    Is Thread is an object ? sleep is a method? I never created a object called Thread then how can it exists.


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    Super Moderator Norm's Avatar
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    Default Re: I'm vary new to java programming and confused about som concepts.

    Thread is a class and sleep is a static method in that class.
    Have you read the API doc for the Thread class?
    The API doc is here: Java Platform SE 6
    Find the Thread class in the lower left and click on it to bring the doc into the righthand frame.
    Read in the tutorials about static methods and variables.

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    Default Re: I'm vary new to java programming and confused about som concepts.

    java.lang.Thread is a class. The Java compiler automatically resolves references to java.lang.* classes as though you had included the line "import java.lang.*;" in your source.

    Thread (Java 2 Platform SE 5.0)

    sleep(int) is declared static, so you can access the method from the class without needing an instance of Thread.

    The Thread API is a bit of a mess. I wish the Sun developers had made sleep a member method so that to sleep your current thread, you'd have to use "Thread.currentThread().sleep(1000);" - which is probably what the current method does internally. Note that you can do this anyway, but the reference from currentThread() would be redundant.

    edit: 1 minute later than Norm as usual. I'm going to have to start my own Java programming forum

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    Default Re: I'm vary new to java programming and confused about som concepts.

    Yea since sleep is a static method?

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    Default Re: I'm vary new to java programming and confused about som concepts.

    Are you asking a question?

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    Default Re: I'm vary new to java programming and confused about som concepts.

    yes because I'm very new to java.

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    Default Re: I'm vary new to java programming and confused about som concepts.

    What is the question?

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    Default Re: I'm vary new to java programming and confused about som concepts.

    you answered in #2 that what I understood is sleep is a static method hence it invoked with out actually creating an object reference variable. right?

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    Default Re: I'm vary new to java programming and confused about som concepts.

    right?
    Sorry, I don't understand your question. Do you understand the previous posts?

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    Default Re: I'm vary new to java programming and confused about som concepts.

    I'm asking what I have understand is right or wrong?

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    Super Moderator Norm's Avatar
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    Default Re: I'm vary new to java programming and confused about som concepts.

    I understood is sleep is a static method hence it invoked with out actually creating an object reference variable
    yes that sounds right.

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    Default Re: I'm vary new to java programming and confused about som concepts.

    If you are beginner, you must not start with threads but with classes first.

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    Default Re: I'm vary new to java programming and confused about som concepts.

    sleep example:

    ...
    thread.sleep(2000);
    textarea.append("this Message displays after 2 seconds!");
    thread.sleep(5000);
    textarea.append("This Message displays after 5 seconds!");
    thread.sleep(1000);
    System.out.println("This Message will display on the console after 1 second!");
    ...

    Although i wouldn't recommend using sleep when appending to a JTextArea, Due to it causing your program to freeze for the ammount of sleep time. Instead you would use a "timer".

    Timer example on oracle: http://download.oracle.com/javase/tu...isc/timer.html

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    Default Re: I'm vary new to java programming and confused about som concepts.

    @macko
    What happens when you execute the code you posted?
    Does it do what you want it to do? What do you want the code to do?

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    Default Re: I'm vary new to java programming and confused about som concepts.

    Quote Originally Posted by Norm View Post
    @macko
    What happens when you execute the code you posted?
    Does it do what you want it to do? What do you want the code to do?
    I guess he just tried to present the sleep() concept, as it puts your thread to sleep condition for number of milliseconds/nanoseconds.

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    Default Re: I'm vary new to java programming and confused about som concepts.

    @Mr.777
    correct....

    Just a demonstration of a spot never to use a sleep

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