Name: agR10195 Date: 02/18/2004


The test Bug.java reveals that setCollectionUsageThreshold() sometimes does not
throw IllegalArgumentException, if threshold is greater than maximum amount of
memory that the pool can use.

The test tries to set threshold max+1 and expects IllegalArgumentException
to be thrown. The exception is thrown just for one pool: "Survivor Space 2".

Please, note that getCollectionUsage() returns MemoryUsage that has zeroes
instead of init, used, committed, max for each pool.

import java.io.*;
import java.util.*;
import java.lang.management.*;

public class Bug {
    public static void main(String[] argv) {
        List pools = ManagementFactory.getMemoryPoolMBeans();

        for (int i = 0; i < pools.size(); i++) {
            MemoryPoolMBean pool = (MemoryPoolMBean) pools.get(i);
            System.out.println("\n" + i + " pool " + pool.getName());

            boolean isSupported = pool.isCollectionUsageThresholdSupported();
            if (!isSupported) {
                System.out.println(" does not support collection usage "
                                 + "thresholds");
                continue;
            }
            System.out.println(" supports collection usage thresholds");
                                 
            MemoryUsage usage = pool.getCollectionUsage();
            if (usage == null) {
                System.out.println(" usage is null");
                continue;
            }
            
            long max = Math.abs(usage.getMax());
            try {
                pool.setCollectionUsageThreshold(max + 1);
                System.out.println(" ERROR: IllegalArgumentException is not "
                                 + "thrown for threshold " + (max + 1) + " ("
                                 + pool.getCollectionUsage() + ")");
            } catch (IllegalArgumentException e) {
                System.out.println(" OK: IllegalArgumentException is thrown "
                                 + "for threshold " + (max + 1) + " ("
                                 + pool.getCollectionUsage() + ")");
            }
        }
    }
}

% ../jdk1.5.0-b38/solaris-sparc/bin/java Bug

0 pool Code Cache
  does not support collection usage thresholds

1 pool Eden Space
  supports collection usage thresholds
  ERROR: IllegalArgumentException is not thrown for threshold 1 (init = 0(0K)
used = 0(0K) committed = 0 (0K)max = 0(0K) )

2 pool Survivor Space 1
  supports collection usage thresholds
  ERROR: IllegalArgumentException is not thrown for threshold 1 (init = 0(0K)
used = 0(0K) committed = 0 (0K)max = 0(0K) )

3 pool Survivor Space 2
  supports collection usage thresholds
  OK: IllegalArgumentException is thrown for threshold 1 (init = 0(0K) used =
0(0K) committed = 0 (0K)max = 0(0K) )

4 pool Tenured Gen
  supports collection usage thresholds
  ERROR: IllegalArgumentException is not thrown for threshold 1 (init = 0(0K)
used = 0(0K) committed = 0 (0K)max = 0(0K) )

5 pool Perm Gen
  supports collection usage thresholds
  ERROR: IllegalArgumentException is not thrown for threshold 1 (init = 0(0K)
used = 0(0K) committed = 0 (0K)max = 0(0K) )

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