HeapUsageMonitor() {
int c = 0;
for (MemoryPoolMXBean m : ManagementFactory.getMemoryPoolMXBeans()) {
if (m.getType() != MemoryType.HEAP) // only interested in HEAP
continue;
if (m.isCollectionUsageThresholdSupported() && m.isUsageThresholdSupported()) {
// should be Old pool, get called when memory is critical
_oldGenBean = m;
_gc_callback = MEM_MAX;
// Really idiotic API: no idea what the usageThreshold is, so I have
// to guess. Start high, catch IAE & lower by 1/8th and try again.
while (true) {
try {
m.setCollectionUsageThreshold(_gc_callback);
break;
} catch (IllegalArgumentException iae) {
// Do NOT log this exception, it is expected and unavoidable and
// entirely handled.
_gc_callback -= (_gc_callback >> 3);
}
}
NotificationEmitter emitter = (NotificationEmitter) _allMemBean;
emitter.addNotificationListener(this, null, m);
++c;
}
}
assert c == 1;
}
private static void checkGarbageCollectionNotificationInfoContent(
GarbageCollectionNotificationInfo notif) throws Exception {
System.out.println("GC notification for " + notif.getGcName());
System.out.print("Action: " + notif.getGcAction());
System.out.println(" Cause: " + notif.getGcCause());
GcInfo info = notif.getGcInfo();
System.out.print("GC Info #" + info.getId());
System.out.print(" start:" + info.getStartTime());
System.out.print(" end:" + info.getEndTime());
System.out.println(" (" + info.getDuration() + "ms)");
Map<String, MemoryUsage> usage = info.getMemoryUsageBeforeGc();
List<String> pnames = new ArrayList<String>();
for (Map.Entry entry : usage.entrySet()) {
String poolname = (String) entry.getKey();
pnames.add(poolname);
MemoryUsage busage = (MemoryUsage) entry.getValue();
MemoryUsage ausage = (MemoryUsage) info.getMemoryUsageAfterGc().get(poolname);
if (ausage == null) {
throw new RuntimeException("After Gc Memory does not exist" + " for " + poolname);
}
System.out.println("Usage for pool " + poolname);
System.out.println(" Before GC: " + busage);
System.out.println(" After GC: " + ausage);
}
// check if memory usage for all memory pools are returned
List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();
for (MemoryPoolMXBean p : pools) {
if (!pnames.contains(p.getName())) {
throw new RuntimeException(
"GcInfo does not contain " + "memory usage for pool " + p.getName());
}
}
}
/**
* Prints the verbose GC log to System.out to list the memory usage of all memory pools as well as
* the GC statistics.
*/
public void printVerboseGc() {
System.out.println("Uptime: " + formatMillis(rmbean.getUptime()));
System.out.println("Heap usage: " + mmbean.getHeapMemoryUsage());
System.out.println("Non-Heap memory usage: " + mmbean.getNonHeapMemoryUsage());
for (GarbageCollectorMXBean gc : gcmbeans) {
System.out.print(" [" + gc.getName() + ": ");
System.out.print("Count=" + gc.getCollectionCount());
System.out.print(" GCTime=" + formatMillis(gc.getCollectionTime()));
System.out.print("]");
}
System.out.println();
for (MemoryPoolMXBean p : pools) {
System.out.print(" [" + p.getName() + ":");
MemoryUsage u = p.getUsage();
System.out.print(" Used=" + formatBytes(u.getUsed()));
System.out.print(" Committed=" + formatBytes(u.getCommitted()));
System.out.println("]");
}
}
public static void main(String[] argv) throws Exception {
memory = new ObjectName(MEMORY_MXBEAN_NAME);
runtime = new ObjectName(RUNTIME_MXBEAN_NAME);
thread = new ObjectName(THREAD_MXBEAN_NAME);
os = new ObjectName(OPERATING_SYSTEM_MXBEAN_NAME);
List<MemoryPoolMXBean> pools = getMemoryPoolMXBeans();
for (MemoryPoolMXBean p : pools) {
if (heapPool == null
&& p.getType() == MemoryType.HEAP
&& p.isUsageThresholdSupported()
&& p.isCollectionUsageThresholdSupported()) {
heapPool = new ObjectName(MEMORY_POOL_MXBEAN_DOMAIN_TYPE + ",name=" + p.getName());
}
if (nonHeapPool == null
&& p.getType() == MemoryType.NON_HEAP
&& p.isUsageThresholdSupported()) {
nonHeapPool = new ObjectName(MEMORY_POOL_MXBEAN_DOMAIN_TYPE + ",name=" + p.getName());
}
}
// Check notification emitters
MyListener listener = new MyListener();
server.addNotificationListener(memory, listener, null, null);
server.removeNotificationListener(memory, listener);
checkEnum();
checkList();
checkMap();
checkMemoryUsage();
checkThreadInfo();
checkOS();
checkSunGC();
System.out.println("Test passed.");
}