Migrated source code from Simantics SVN

[simantics/platform.git] / bundles / org.simantics.diagram / src / org / simantics / diagram / content / DiagramContentTracker.java

diff --git a/bundles/org.simantics.diagram/src/org/simantics/diagram/content/DiagramContentTracker.java b/bundles/org.simantics.diagram/src/org/simantics/diagram/content/DiagramContentTracker.java
new file mode 100644 (file)
index 0000000..1cd506e
--- /dev/null
+++ b/bundles/org.simantics.diagram/src/org/simantics/diagram/content/DiagramContentTracker.java
@@ -0,0 +1,90 @@
+/*******************************************************************************\r
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
+ * in Industry THTH ry.\r
+ * All rights reserved. This program and the accompanying materials\r
+ * are made available under the terms of the Eclipse Public License v1.0\r
+ * which accompanies this distribution, and is available at\r
+ * http://www.eclipse.org/legal/epl-v10.html\r
+ *\r
+ * Contributors:\r
+ *     VTT Technical Research Centre of Finland - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.diagram.content;\r
+\r
+import org.simantics.db.RequestProcessor;\r
+import org.simantics.db.Resource;\r
+import org.simantics.db.Session;\r
+import org.simantics.db.exception.DatabaseException;\r
+import org.simantics.diagram.adapter.DiagramContentRequest;\r
+import org.simantics.diagram.synchronization.ErrorHandler;\r
+import org.simantics.g2d.canvas.ICanvasContext;\r
+import org.simantics.utils.ui.ErrorLogger;\r
+\r
+/**\r
+ * A utility for requesting a diagram's contents and keeping track of them and\r
+ * obtaining differences.\r
+ * \r
+ * <p>\r
+ * This class is not thread-safe.\r
+ * \r
+ * @author Tuukka Lehtonen\r
+ */\r
+public class DiagramContentTracker {\r
+\r
+    private final ErrorHandler errorHandler = new ErrorHandler() {\r
+        @Override\r
+        public void warning(String message, Exception e) {\r
+            ErrorLogger.defaultLogWarning(message, e);\r
+        }\r
+        @Override\r
+        public void error(String message, Throwable t) {\r
+            ErrorLogger.defaultLogError(message, t);\r
+        }\r
+    };\r
+\r
+    private DiagramContents       lastContents   = new DiagramContents();\r
+    private DiagramContentChanges lastDifference = DiagramContentChanges.EMPTY;\r
+\r
+    private final ICanvasContext  context;\r
+    private final Session         session;\r
+    private final Resource        diagram;\r
+\r
+    public static DiagramContentTracker start(ICanvasContext context, RequestProcessor processor, Resource diagram) throws DatabaseException {\r
+        DiagramContentTracker tracker = new DiagramContentTracker(context, processor.getSession(), diagram);\r
+        tracker.update(processor);\r
+        return tracker;\r
+    }\r
+\r
+    private DiagramContentTracker(ICanvasContext context, Session session, Resource diagram) {\r
+        if (context == null)\r
+            throw new NullPointerException("null canvas context");\r
+        if (session == null)\r
+            throw new NullPointerException("null session");\r
+        if (diagram == null)\r
+            throw new NullPointerException("null diagram");\r
+        this.context = context;\r
+        this.session = session;\r
+        this.diagram = diagram;\r
+    }\r
+\r
+    public DiagramContentChanges update() throws DatabaseException {\r
+        return update(session);\r
+    }\r
+\r
+    public DiagramContentChanges update(RequestProcessor processor) throws DatabaseException {\r
+        DiagramContents contents = processor.syncRequest(new DiagramContentRequest(context, diagram, errorHandler));\r
+        DiagramContentChanges changes = contents.differenceFrom(lastContents);\r
+        this.lastDifference = changes;\r
+        this.lastContents = contents;\r
+        return changes;\r
+    }\r
+\r
+    public DiagramContents getLastContents() {\r
+        return lastContents;\r
+    }\r
+\r
+    public DiagramContentChanges getLastDifference() {\r
+        return lastDifference;\r
+    }\r
+\r
+}\r