X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=blobdiff_plain;f=bundles%2Forg.simantics.db.common%2Fsrc%2Forg%2Fsimantics%2Fdb%2Fcommon%2Fprocedure%2Fadapter%2FStagedAsyncListener.java;fp=bundles%2Forg.simantics.db.common%2Fsrc%2Forg%2Fsimantics%2Fdb%2Fcommon%2Fprocedure%2Fadapter%2FStagedAsyncListener.java;h=15c5b62990b574d7034d790983818c1f076c53ae;hb=969bd23cab98a79ca9101af33334000879fb60c5;hp=0000000000000000000000000000000000000000;hpb=866dba5cd5a3929bbeae85991796acb212338a08;p=simantics%2Fplatform.git

diff --git a/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/adapter/StagedAsyncListener.java b/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/adapter/StagedAsyncListener.java
new file mode 100644
index 000000000..15c5b6299
--- /dev/null
+++ b/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/adapter/StagedAsyncListener.java
@@ -0,0 +1,44 @@
+/*******************************************************************************
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management
+ * in Industry THTH ry.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     VTT Technical Research Centre of Finland - initial API and implementation
+ *******************************************************************************/
+package org.simantics.db.common.procedure.adapter;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import org.simantics.db.AsyncReadGraph;
+import org.simantics.db.procedure.AsyncListener;
+
+abstract public class StagedAsyncListener<T> implements AsyncListener<T> {
+
+	final private AtomicBoolean first = new AtomicBoolean(true); 
+	
+	@Override
+    public void exception(AsyncReadGraph graph, Throwable t) {
+    }
+
+    @Override
+    final public void execute(AsyncReadGraph graph, T result) {
+    	if(first.compareAndSet(true, false)) {
+    		first(graph, result);
+    	} else {
+    		rest(graph, result);
+    	}
+    }
+
+    @Override
+    public boolean isDisposed() {
+        return false;
+    }
+
+    abstract public void first(AsyncReadGraph graph, T result);
+    abstract public void rest(AsyncReadGraph graph, T result);
+
+}