X-Git-Url: https://gerrit.simantics.org/r/gitweb?p=simantics%2Fplatform.git;a=blobdiff_plain;f=bundles%2Forg.simantics.db.common%2Fsrc%2Forg%2Fsimantics%2Fdb%2Fcommon%2Fprocedure%2Fsingle%2Fwrapper%2FNullSingleOrNullProcedure.java;fp=bundles%2Forg.simantics.db.common%2Fsrc%2Forg%2Fsimantics%2Fdb%2Fcommon%2Fprocedure%2Fsingle%2Fwrapper%2FNullSingleOrNullProcedure.java;h=15523b9d3fbfdc778dc776dcea4acacab35eb192;hp=0000000000000000000000000000000000000000;hb=969bd23cab98a79ca9101af33334000879fb60c5;hpb=866dba5cd5a3929bbeae85991796acb212338a08

diff --git a/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/single/wrapper/NullSingleOrNullProcedure.java b/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/single/wrapper/NullSingleOrNullProcedure.java
new file mode 100644
index 000000000..15523b9d3
--- /dev/null
+++ b/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/single/wrapper/NullSingleOrNullProcedure.java
@@ -0,0 +1,89 @@
+/*******************************************************************************
+ * 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.single.wrapper;
+
+import org.simantics.db.AsyncReadGraph;
+import org.simantics.db.common.utils.Logger;
+import org.simantics.db.procedure.AsyncProcedure;
+
+final public class NullSingleOrNullProcedure<Result> {
+
+	private Result result = null;
+	final AsyncProcedure<Result> procedure;
+	
+	boolean done = false;
+	boolean found = false;
+	int ready = 1;
+	
+//	final AtomicBoolean done = new AtomicBoolean(false);
+//	final AtomicBoolean found = new AtomicBoolean(false);
+//	final AtomicInteger ready = new AtomicInteger(1);
+
+	public NullSingleOrNullProcedure(AsyncProcedure<Result> procedure) {
+
+		this.procedure = procedure;
+
+	}
+
+	public void inc() {
+		ready++;
+//		ready.incrementAndGet();
+	}
+
+	public void dec(AsyncReadGraph graph) {
+
+		if((--ready) == 0) {
+			// Shall fire exactly once!
+			if(!done) {
+				done = true;
+				try {
+					procedure.execute(graph, result);
+				} catch (Throwable t) {
+		    		Logger.defaultLogError(t);
+				}
+			}
+		}
+
+	}
+
+	public void offer(AsyncReadGraph graph, Result result) {
+
+		if(!found) {
+			found = true;
+			this.result = result;
+		} else {
+			// Shall fire exactly once!
+			if(!done) {
+				done = true;
+				try {
+					procedure.execute(graph, null);
+				} catch (Throwable t) {
+		    		Logger.defaultLogError(t);
+				}
+			}
+		}
+
+	}
+
+	public void exception(AsyncReadGraph graph, Throwable t) {
+		// Shall fire exactly once!
+		if(!done) {
+			done = true;
+			try {
+				procedure.exception(graph, t);
+			} catch (Throwable t2) {
+	    		Logger.defaultLogError(t2);
+			}
+		}
+	}
+
+}