X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=blobdiff_plain;f=org.simantics.g3d%2Fsrc%2Forg%2Fsimantics%2Fg3d%2Fscenegraph%2Fbase%2FParentNode.java;h=5c834fba1dd8b89233f1dbc4e33c5f9a30fb42a4;hb=5750b207d04063d1b2f0128eb5296d22ffec302e;hp=7da387d7fa5866ae6a5e6117000ee6b48837c044;hpb=53d55c24c779745f188bdb18d32f71d20acb61b2;p=simantics%2F3d.git

diff --git a/org.simantics.g3d/src/org/simantics/g3d/scenegraph/base/ParentNode.java b/org.simantics.g3d/src/org/simantics/g3d/scenegraph/base/ParentNode.java
index 7da387d7..5c834fba 100644
--- a/org.simantics.g3d/src/org/simantics/g3d/scenegraph/base/ParentNode.java
+++ b/org.simantics.g3d/src/org/simantics/g3d/scenegraph/base/ParentNode.java
@@ -12,7 +12,6 @@
 package org.simantics.g3d.scenegraph.base;
 
 import java.util.ArrayList;
-import java.util.Collection;
 import java.util.List;
 
 import org.simantics.utils.datastructures.MapList;
@@ -22,8 +21,13 @@ public abstract class ParentNode<T extends INode> extends Node {
 	private MapList<String, T> children = new MapList<String, T>();
 
 	public synchronized void addNode(String relName, T child) {
-		if (child.getParent() != null)
+	    if (child == null)
+	        throw new NullPointerException("Cannot add null child");
+		if (child.getParent() != null) {
+		    if (child.getParent() == this)
+		        throw new IllegalArgumentException("Given node is already a child");
 			child.getParent().deattachNode(child.getParentRel(), child);
+		}
 
 		child.setParent(this, relName);
 		children.add(relName, (T) child);