Bug 561328: SLeak provide a smarter diff

Compare stack-traces of removed, old objects and new objects, to find
resources that were disposed and recreated.

This work was done by Conrad, and simply split into new commits
by me.

Signed-off-by: Jonah Graham <jonah@kichwacoders.com>
Also-by: Conrad Groth <info@conrad-groth.de>
Change-Id: Ic63eda5b67a89ef32e3973fd05c203df0714d9a5
Reviewed-on: https://git.eclipse.org/r/c/platform/eclipse.platform.swt/+/175119
Tested-by: Lars Vogel <Lars.Vogel@vogella.com>
Reviewed-by: Lars Vogel <Lars.Vogel@vogella.com>

1 files changed, 43 insertions, 0 deletions

diff --git a/bundles/org.eclipse.swt.tools.spies/src/org/eclipse/swt/tools/internal/Sleak.java b/bundles/org.eclipse.swt.tools.spies/src/org/eclipse/swt/tools/internal/Sleak.java
index 641e3f7d78..00551940aa 100644
--- a/bundles/org.eclipse.swt.tools.spies/src/org/eclipse/swt/tools/internal/Sleak.java
+++ b/bundles/org.eclipse.swt.tools.spies/src/org/eclipse/swt/tools/internal/Sleak.java
@@ -34,6 +34,7 @@ public class Sleak {
 	List list;
 	Canvas canvas;
 	Button enableTracking, snapshot, diff, stackTrace, saveAs, save;
+	Combo diffType;
 	Text text;
 	Label label;
 
@@ -108,6 +109,12 @@ public void create (Composite parent) {
 	diff.setText ("Diff");
 	diff.addListener (SWT.Selection, event -> refreshDifference ());
 	diff.setLayoutData(new GridData(SWT.FILL, SWT.NONE, false, false));
+	diffType = new Combo (parent, SWT.CHECK);
+	diffType.add ("Object identity");
+	diffType.add ("Creator class and line");
+	diffType.add ("Creator class");
+	diffType.select(0);
+	diffType.setLayoutData(new GridData(SWT.FILL, SWT.NONE, false, false));
 	stackTrace = new Button (parent, SWT.CHECK);
 	stackTrace.setText ("Stack");
 	stackTrace.addListener (SWT.Selection, e -> toggleStackTrace ());
@@ -194,6 +201,19 @@ void refreshDifference () {
 			}
 		}
 	}
+	if (diffType.getSelectionIndex() > 0) {
+		Iterator<ObjectWithError> object = objects.iterator ();
+		while (object.hasNext ()) {
+			StackTraceElement stack = object.next ().getCreator ();
+			Iterator<ObjectWithError> old = oldObjects.iterator ();
+			while (old.hasNext ()) {
+				if (creatorEquals(stack, old.next().getCreator ())) {
+					old.remove ();
+					object.remove ();
+				}
+			}
+		}
+	}
 	list.removeAll ();
 	text.setText ("");
 	canvas.redraw ();
@@ -203,6 +223,13 @@ void refreshDifference () {
 	refreshLabel ();
 }
 
+boolean creatorEquals (StackTraceElement first, StackTraceElement second) {
+	switch (diffType.getSelectionIndex()) {
+		case 1: return first.equals(second);
+		case 2: return first.getClassName().equals(second.getClassName());
+		default: throw new IllegalArgumentException();
+	}
+}
 private void saveToFile(boolean prompt) {
 	if (prompt || selectedName == null) {
 		FileDialog dialog = new FileDialog(saveAs.getShell(), SWT.SAVE);
@@ -381,12 +408,28 @@ private static final class ObjectWithError {
 	final Object object;
 	final Error error;
 	String stack;
+	StackTraceElement creator;
 
 	ObjectWithError(Object o, Error e) {
 		this.object = o;
 		this.error = e;
 	}
 
+	StackTraceElement getCreator() {
+		if (creator == null) {
+			String objectType = object.getClass().getName();
+			Iterator<StackTraceElement> stack = Arrays.asList(error.getStackTrace()).iterator();
+			while (stack.hasNext()) {
+				StackTraceElement element = stack.next();
+				if (element.getClassName().equals(objectType) && element.getMethodName().equals("<init>")) {
+					creator = stack.hasNext() ? stack.next() : null;
+					break;
+				}
+			}
+		}
+		return creator;
+	}
+
 	String getStack() {
 		if (stack == null) {
 			ByteArrayOutputStream stream = new ByteArrayOutputStream();