--- a/src/treecms/memory/OnMemoryNode.java	Tue Jul 12 14:39:35 2011 +0900
+++ b/src/treecms/memory/OnMemoryNode.java	Mon Jul 18 20:22:53 2011 +0900
@@ -4,6 +4,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+
 import treecms.api.Node;
 import treecms.api.NodeAttributes;
 import treecms.api.NodeID;
@@ -83,19 +84,19 @@
 	}
 
 	@Override
-	public Node create(NodeAttributes _attr)
+	public OnMemoryNode create(NodeAttributes _attr)
 	{
 		throw new UnsupportedOperationException(ERR_READONLY);
 	}
 
 	@Override
-	public Node remove(String _uuid)
+	public OnMemoryNode remove(String _uuid)
 	{
 		throw new UnsupportedOperationException(ERR_READONLY);
 	}
 
 	@Override
-	public Node remove(int _index)
+	public OnMemoryNode remove(int _index)
 	{
 		throw new UnsupportedOperationException(ERR_READONLY);
 	}