what is the value for main thread priority?

Question

all threads have its priority,so what is the integer value for main thread?

Answer 1

This code shows you the priority of the main thread:

public class Main {
    public static void main( String [] args ) {
        System.out.println( Thread.currentThread().getPriority() );
    }
}

The output, and the answer to your question, is 5.

Answer 2

If you still have any doubts, have a look at the JDK's API docs:

From http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Thread.html#NORM_PRIORITY:

NORM_PRIORITY

public static final int NORM_PRIORITY

    The default priority that is assigned to a thread.

From http://java.sun.com/j2se/1.5.0/docs/api/constant-values.html#java.lang.Thread.NORM_PRIORITY:

static final int NORM_PRIORITY 5