X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=blobdiff_plain;f=bundles%2Forg.simantics.db.common%2Fsrc%2Forg%2Fsimantics%2Fdb%2Fcommon%2Fprocedure%2Fsingle%2Fwrapper%2FDeepSingleOrErrorProcedure.java;fp=bundles%2Forg.simantics.db.common%2Fsrc%2Forg%2Fsimantics%2Fdb%2Fcommon%2Fprocedure%2Fsingle%2Fwrapper%2FDeepSingleOrErrorProcedure.java;h=3a78245befa635f113fd45c7a6d020cb3789c0fc;hb=969bd23cab98a79ca9101af33334000879fb60c5;hp=0000000000000000000000000000000000000000;hpb=866dba5cd5a3929bbeae85991796acb212338a08;p=simantics%2Fplatform.git

diff --git a/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/single/wrapper/DeepSingleOrErrorProcedure.java b/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/single/wrapper/DeepSingleOrErrorProcedure.java
new file mode 100644
index 000000000..3a78245be
--- /dev/null
+++ b/bundles/org.simantics.db.common/src/org/simantics/db/common/procedure/single/wrapper/DeepSingleOrErrorProcedure.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 java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.simantics.db.AsyncReadGraph;
+import org.simantics.db.common.utils.Logger;
+import org.simantics.db.exception.NoSingleResultException;
+import org.simantics.db.procedure.AsyncProcedure;
+
+final public class DeepSingleOrErrorProcedure<Result> {
+    
+	private Result result = null;
+	final AsyncProcedure<Result> procedure;
+    final AtomicBoolean done = new AtomicBoolean(false);
+    final AtomicBoolean found = new AtomicBoolean(false);
+    final AtomicInteger ready = new AtomicInteger(1);
+    
+    public DeepSingleOrErrorProcedure(AsyncProcedure<Result> procedure) {
+        
+        this.procedure = procedure;
+        
+    }
+    
+    public void inc() {
+        
+        ready.incrementAndGet();
+        
+    }
+    
+    public void dec(AsyncReadGraph graph) {
+
+        if(ready.decrementAndGet() == 0) {
+			// Shall fire exactly once!
+            if(done.compareAndSet(false, true)) {
+            	try {
+            		if(found.compareAndSet(false, true)) {
+    					procedure.exception(graph, new NoSingleResultException("No results."));
+            		} else {
+    					procedure.execute(graph, result);
+            		}
+            	} catch (Throwable t) {
+            		Logger.defaultLogError(t);
+            	}
+            }
+        }
+        
+    }
+
+    public void offer(AsyncReadGraph graph, Result result) {
+        
+		if(found.compareAndSet(false, true)) {
+			this.result = result;
+		} else {
+			// Shall fire exactly once!
+			if(done.compareAndSet(false, true)) {
+				try {
+					procedure.exception(graph, new NoSingleResultException(this.result + " and " + result));
+				} catch (Throwable t) {
+		    		Logger.defaultLogError(t);
+				}
+			}
+		}
+        
+    }
+    
+    public void exception(AsyncReadGraph graph, Throwable t) {
+		// Shall fire exactly once!
+		if(done.compareAndSet(false, true)) {
+			try {
+				procedure.exception(graph, t);
+			} catch (Throwable t2) {
+	    		Logger.defaultLogError(t2);
+			}
+		}
+    }
+	
+}