class ReferrersFiller { // This many instances of this are created. staticint FILLER_COUNT = 20000; static ReferrersFiller[] lotsAndLots = new ReferrersFiller[
ReferrersFiller.FILLER_COUNT]; int xx;
ReferrersFiller(int p1) {
xx = p1;
}
}
class ReferrersTarg { // This many instances + 1 of this class are created. staticint TARG_COUNT = 10; static ReferrersTarg theReferrersTarg; static ReferrersTarg[] allReferrersTargs;
// Each instance will point to the theReferrersTarg
ReferrersTarg oneReferrersTarg;
publicstaticvoid bkpt() {
}
publicstaticvoid main(String[] args) {
System.out.println("Howdy!"); for (int ii = 0; ii < ReferrersFiller.lotsAndLots.length; ii++) {
ReferrersFiller.lotsAndLots[ii] = new ReferrersFiller(ii);
}
theReferrersTarg = new ReferrersTarg();
allReferrersTargs = new ReferrersTarg[ReferrersTarg.TARG_COUNT]; for (int ii = 0; ii < ReferrersTarg.TARG_COUNT; ii++) {
allReferrersTargs[ii] = new ReferrersTarg();
allReferrersTargs[ii].oneReferrersTarg = theReferrersTarg;
}
bkpt();
System.out.println("Goodbye from ReferrersTarg!");
}
}
if (targetName.equals("ReferrersTarg")) {
resumeTo("ReferrersTarg", "bkpt", "()V");
} else { // Let debuggee run for awhile to get classes loaded
vm().resume(); try {
System.err.println("Press <enter> to continue");
System.in.read();
System.err.println("running...");
} catch(Exception e) {
}
vm().suspend();
}
// Get all classes. long start = System.currentTimeMillis();
List<ReferenceType> allClasses = vm().allClasses(); long end = System.currentTimeMillis();
System.out.println( allClasses.size() + " classes from vm.allClasses() took " +
(end - start) + " ms");
long[] counts;
// Test for NPE
{ boolean pass = false; try {
counts = vm().instanceCounts(null);
} catch (NullPointerException ee) {
pass = true;
} if (!pass) {
failure("failure: NullPointerException not thrown on instanceCounts(null)");
}
}
// Test for 0 length array
{
List<ReferenceType>someClasses = new ArrayList(2);
counts = vm().instanceCounts(someClasses); if (counts.length != 0) {
failure("failure: instanceCounts with a zero length array fails: " +
counts.length);
}
}
// Test various values of maxInstances if (targetClass.name().equals("ReferrersTarg")) {
List<ObjectReference> noInstances = targetClass.instances(0); if (noInstances.size() != ReferrersTarg.TARG_COUNT + 1) {
failure("failure: instances(0): " + noInstances.size() + ", for " + targetClass);
}
noInstances = targetClass.instances(1); if (noInstances.size() != 1) {
failure("failure: instances(1): " + noInstances.size() + ", for " + targetClass);
} boolean pass = false; try {
noInstances = targetClass.instances(-1);
} catch (IllegalArgumentException ee) {
pass = true;
} if (!pass) {
failure("failure: instances(-1) did not get an exception");
}
}
// Instance counts for all classes
start = System.currentTimeMillis();
counts = vm().instanceCounts(allClasses);
end = System.currentTimeMillis();
if (counts.length == 0) {
System.out.println("failure: No instances found"); thrownew Exception("ReferrersTest: failed");
}
// Create a list of ReferenceTypes sorted by instance count int size = 0;
List<ToSort> sorted = new ArrayList(allClasses.size()); for (int ii = 0; ii < allClasses.size(); ii++) {
size += counts[ii];
ToSort tos = new ToSort(counts[ii], allClasses.get(ii));
sorted.add(tos);
}
System.out.println("instance counts for " + counts.length + " classes got " + size + " instances and took " +
(end - start) + " ms");
Collections.sort(sorted); for (int ii = sorted.size() - 1; ii >= 0 ; ii--) {
ToSort xxx = sorted.get(ii);
if (xxx.rt.name().equals("ReferrersFiller") &&
xxx.count == ReferrersFiller.FILLER_COUNT) {
gotReferrersFiller = true;
} if (xxx.rt.name().equals("ReferrersTarg") &&
xxx.count == ReferrersTarg.TARG_COUNT + 1) {
gotReferrersTarg = true;
}
} if (!gotReferrersFiller) {
failure("failure: Expected " + ReferrersFiller.FILLER_COUNT + " instances of ReferrersFiller");
} if (!gotReferrersTarg) {
failure("failure: Expected " + (ReferrersTarg.TARG_COUNT + 1) + " instances of ReferrersTarg");
}
List<List<ObjectReference>> allInstances = new ArrayList(10);
// Instances, one class at a time, in sorted order, printing each line if (true) {
System.out.println("\nGetting instances for one class " + "at a time (limited) in sorted order");
List<ReferenceType> rtList = new ArrayList(1);
rtList.add(null); long start1 = System.currentTimeMillis();
size = 0; long count = 0; for (int ii = sorted.size() - 1; ii >= 0 ; ii--) {
ToSort xxx = sorted.get(ii); if (xxx.count <= CUT_OFF) { break;
}
rtList.set(0, xxx.rt);
start = System.currentTimeMillis();
List<ObjectReference> oneInstances = xxx.rt.instances(19999999);
end = System.currentTimeMillis();
size += oneInstances.size();
count++;
System.out.println("Expected " + xxx.count + " instances, got " +
oneInstances.size() + " instances for " + sorted.get(ii).rt + " in " + (end - start) + " ms");
System.out.println(size + " instances via making one vm.instances" + " call for each of " + count + " classes took " + (end - start1) + " ms");
System.out.println("Per class = " +
(end - start) / allClasses.size() + " ms");
}
// referrers
// Test various values of maxReferrers if (targetClass.name().equals("ReferrersTarg")) {
Field field1 = targetClass.fieldByName("theReferrersTarg");
ObjectReference anInstance = (ObjectReference)targetClass.getValue(field1);
List<ObjectReference> noReferrers = anInstance.referringObjects(0); if (noReferrers.size() != ReferrersTarg.TARG_COUNT + 1 ) {
failure("failure: referringObjects(0) got " + noReferrers.size() + ", for " + anInstance);
}
noReferrers = anInstance.referringObjects(1); if (noReferrers.size() != 1 ) {
failure("failure: referringObjects(1) got " + noReferrers.size() + ", for " + anInstance);
} boolean pass = false; try {
noReferrers = anInstance.referringObjects(-1);
} catch (IllegalArgumentException ee) {
pass = true;
} if (!pass) {
failure("failure: referringObjects(-1) did not get an exception");
}
}
List<ObjectReference> allReferrers = null;
List<ObjectReference> someInstances = new ArrayList(); if (targetName.equals("ReferrersTarg")) {
Field field1 = targetClass.fieldByName("theReferrersTarg");
ObjectReference val = (ObjectReference)targetClass.getValue(field1);
someInstances.add(val);
allReferrers = val.referringObjects(99999); //LIMIT if (allReferrers.size() != ReferrersTarg.TARG_COUNT + 1) {
failure("failure: expected " + (ReferrersTarg.TARG_COUNT + 1) + "referrers, but got " + allReferrers.size() + " referrers for " + val);
}
} else { // referrers // Create someInstances to find the referrers of. for (int ii = 0; ii < allClasses.size(); ii++) {
List<ObjectReference> objRefList = allInstances.get(ii); if (objRefList != null) { int asize = objRefList.size(); if (false) {
System.out.println(asize + ", " + allClasses.get(ii));
} // Remember one instance per class to get referrers if (asize > 0) {
someInstances.add(objRefList.get(0));
}
}
}
}
for (ObjectReference objRef: someInstances) { //System.out.println( "Getting referrers for " + objRef);
start = System.currentTimeMillis(); if ( true) {
showReferrers(objRef, 0, 0, 0);
} else {
allReferrers = objRef.referringObjects(99999); //LIMIT
end = System.currentTimeMillis(); if (true || allReferrers.size() > 1) {
System.out.println( allReferrers.size() + " referrers for " + objRef + " took " + (end - start) + " ms");
}
}
}
/* *dealwithresultsoftest *ifanythinghascalledfailure("foo")testFailedwillbetrue
*/ if (!testFailed) {
println("ReferrersTest: passed");
} else { thrownew Exception("ReferrersTest: failed");
}
} void indent(int level) { for (int ii = 0; ii < level; ii++) {
System.out.print(" ");
}
}
Map<ObjectReference, Object> visited = new HashMap(100); void showReferrers(ObjectReference objRef, int level, int total, int which) {
if (level == 0) {
visited.clear();
} else { if (visited.containsKey(objRef)) {
indent(level);
System.out.println("(" + which + ")" + ":<pruned> " + objRef); return;
}
visited.put(objRef, null);
indent(level); //System.out.println(which + "/" + total + ": " + objRef + " took " + time + " ms");
}
List<ObjectReference> allReferrers = null;
//System.out.println( "Getting referrers for " + objRef); long start, end;
start = System.currentTimeMillis();
allReferrers = objRef.referringObjects(99999); //LIMIT
end = System.currentTimeMillis();
if (which == 0) {
System.out.println(allReferrers.size() + " referrers for " + objRef + " took " + (end - start) + " ms");
} else {
System.out.println("(" + which + ") " + objRef);
indent(level);
System.out.println(" " + allReferrers.size() + " referrers for " + objRef + " took " + (end - start) + " ms");
}
// We have to stop going up a referrer chain in some cases
Type rt = objRef.type(); if (rt instanceof ClassType) {
ClassType ct = (ClassType)rt;
String name = ct.name(); if (name.equals("sun.awt.SoftCache$ValueCell")) { return;
} if (name.equals("java.lang.ref.Finalizer")) { return;
} if (name.equals("java.lang.ref.SoftReference")) { return;
} // oh oh, should really check for a subclass of ClassLoader :-) if (name.indexOf("ClassLoader") >= 0) { return;
} // No doubt there are other reasons to stop ...
} int itemNumber = 1; int allSize = allReferrers.size(); for (ObjectReference objx: allReferrers) {
showReferrers(objx, level + 1, allSize, itemNumber++);
}
}
}
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Die Informationen auf dieser Webseite wurden
nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit,
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