Name: skR10005 Date: 06/26/2002


The API spec for method ThreadGroup.setMaxPriopity reads

  If the pri argument is less than Thread.MIN_PRIORITY or greater than
  Thread.MAX_PRIORITY, the maximum priority of the group remains unchanged.

The new JCK test
api/java_lang/ThreadGroup/setMaxPriority01/setMaxPriority0105/setMaxPriority0105.html
checks this assertion. However, this test failed under all previous
JDK versions up to JDK 1.4.1-rc.

To reproduce this failure, a simple example can be used:
=================setMaxPriority0105.java=================
import java.io.PrintStream;

public class setMaxPriority0105 {

    public void run(String argv[], PrintStream log, PrintStream out) {

        ThreadGroup thg = new ThreadGroup("setMaxPriority0105");
        int prio = thg.getMaxPriority();
        thg.setMaxPriority(Thread.MIN_PRIORITY - 1);
        if(prio != thg.getMaxPriority()) {
            out.println("thread group priority is changed:" +
                    prio + "-" + thg.getMaxPriority());
        }

    }

    public static void main(String args[]) {
     (new setMaxPriority0105()).run(args, System.err, System.out);
    }

}
========================================================
The log of execution is following:
$ javac -d . setMaxPriority0105.java
$ java -version
java version "1.4.1-rc"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1-rc-b15)
Java HotSpot(TM) Client VM (build 1.4.1-rc-b15, mixed mode)
$ $ java -cp . setMaxPriority0105
thread group priority is changed:10-1

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