From 197f65594b46aaa087ac4d9bb6cb5514376377ca Mon Sep 17 00:00:00 2001
From: Marko Luukkainen <marko.luukkainen@semantum.fi>
Date: Fri, 5 Feb 2021 17:05:35 +0200
Subject: [PATCH] Improved clearing of CanvasContext

gitlab #674


Change-Id: Ib2e6d13346576f6852f30fa31c08adc0b638db13
---
 .../org/simantics/g2d/canvas/impl/CanvasContext.java   |  1 +
 .../datastructures/hints/AbstractHintObservable.java   |  5 +++++
 .../utils/datastructures/hints/HintStack.java          |  5 +++++
 .../datastructures/prioritystack/PriorityStack.java    | 10 ++++++++++
 4 files changed, 21 insertions(+)

diff --git a/bundles/org.simantics.g2d/src/org/simantics/g2d/canvas/impl/CanvasContext.java b/bundles/org.simantics.g2d/src/org/simantics/g2d/canvas/impl/CanvasContext.java
index 998b8a9a2..cf9cff75c 100644
--- a/bundles/org.simantics.g2d/src/org/simantics/g2d/canvas/impl/CanvasContext.java
+++ b/bundles/org.simantics.g2d/src/org/simantics/g2d/canvas/impl/CanvasContext.java
@@ -191,6 +191,7 @@ public class CanvasContext extends Context<ICanvasParticipant> implements ICanva
                 }
                 // HN: added to decrease memory leaks
                 eventHandlerStack = null;
+                hintStack.clear();
                 hintStack = null;
                 canvasNode.cleanup();
                 canvasNode = null;
diff --git a/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/AbstractHintObservable.java b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/AbstractHintObservable.java
index aacadc1a6..bbe2447c9 100644
--- a/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/AbstractHintObservable.java
+++ b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/AbstractHintObservable.java
@@ -255,5 +255,10 @@ public abstract class AbstractHintObservable implements IHintObservable {
 		list.remove(threadAccess, listener);
 		if (list.isEmpty()) keyListeners.remove(key);		
 	}
+	
+	public void clear() {
+		keyListeners.clear();
+		listeners.clear();
+	}
 		
 }
diff --git a/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/HintStack.java b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/HintStack.java
index 2be216d30..d6af390e6 100644
--- a/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/HintStack.java
+++ b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/HintStack.java
@@ -333,4 +333,9 @@ public class HintStack extends AbstractHintObservable implements IHintStack {
 			}};
 	}
 	
+	public void clear() {
+		super.clear();
+		stack.clear();
+	}
+	
 }
diff --git a/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/prioritystack/PriorityStack.java b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/prioritystack/PriorityStack.java
index 81029105d..6c0a36acd 100644
--- a/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/prioritystack/PriorityStack.java
+++ b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/prioritystack/PriorityStack.java
@@ -197,5 +197,15 @@ public class PriorityStack<E> implements IPriorityStack<E> {
 	public String toString() {
 	    return EString.implode(snapshotArray, "\n");
 	}
+	
+	public void clear() {
+		if (list != null) {
+			list.clear();
+		}
+		if (listeners != null) {
+			listeners.clear();
+		}
+		snapshotArray = createArray(0);
+	}
 
 }
-- 
2.47.1