Migrated source code from Simantics SVN

[simantics/platform.git] / bundles / org.simantics.db / src / org / simantics / db / service / QueryControl.java

diff --git a/bundles/org.simantics.db/src/org/simantics/db/service/QueryControl.java b/bundles/org.simantics.db/src/org/simantics/db/service/QueryControl.java
new file mode 100644 (file)
index 0000000..2eaa144
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+++ b/bundles/org.simantics.db/src/org/simantics/db/service/QueryControl.java
@@ -0,0 +1,98 @@
+/*******************************************************************************\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.db.service;\r
+\r
+import java.util.Collection;\r
+\r
+import org.simantics.db.AsyncReadGraph;\r
+import org.simantics.db.ReadGraph;\r
+import org.simantics.db.Resource;\r
+import org.simantics.db.WriteGraph;\r
+import org.simantics.db.procedure.AsyncContextMultiProcedure;\r
+import org.simantics.db.procedure.AsyncMultiProcedure;\r
+import org.simantics.db.request.ExternalRead;\r
+\r
+\r
+/**\r
+ * @author Antti Villberg\r
+ */\r
+public interface QueryControl {\r
+\r
+    interface ControlProcedure {\r
+        void execute(AsyncReadGraph graph);\r
+    }\r
+\r
+    /**\r
+     * \r
+     * @return current amount of queries\r
+     */\r
+    int count();\r
+    \r
+    /**\r
+     * @return The amount of fixed queries after best effort flush\r
+     */\r
+    int flush();\r
+    int flush(ReadGraph graph);\r
+    \r
+    /**\r
+     * \r
+     * @param allowedTimeInMs The amount of allowed time use in ms.\r
+     */\r
+    void gc(ReadGraph graph, int allowedTimeInMs);\r
+\r
+    /**\r
+     * Collects all external read requests and their parent queries that are no\r
+     * longer listened to. Needs to perform exclusive locking of the database\r
+     * client internally so do not invoke this from within a graph read or write\r
+     * request but use {@link #gc(WriteGraph, Collection)} instead.\r
+     * \r
+     * @param reads\r
+     */\r
+    void gc(Collection<ExternalRead<?>> reads);\r
+\r
+    /**\r
+     * Collects all external read requests and their parent queries that are no\r
+     * longer listened to. The write graph argument is used to ensure that the\r
+     * invocation is performed from within a write request with exclusive\r
+     * locking.\r
+     * \r
+     * @param graph write request handle\r
+     * @param reads the external read requests to attempt garbage collection for\r
+     */\r
+    void gc(WriteGraph graph, Collection<ExternalRead<?>> reads);\r
+\r
+    int getAmountOfQueryThreads();\r
+\r
+    int getGraphThread(AsyncReadGraph graph);\r
+    \r
+    boolean resume(AsyncReadGraph graph);\r
+\r
+    void schedule(AsyncReadGraph graph, int targetThread, ControlProcedure procedure);\r
+\r
+    boolean scheduleByCluster(AsyncReadGraph graph, Resource resource, AsyncMultiProcedure<Resource> procedure);\r
+    <C> boolean scheduleByCluster(AsyncReadGraph graph, Resource resource, C context, AsyncContextMultiProcedure<C, Resource> procedure);\r
+\r
+    /**\r
+     * Returns a new ReadGraph based on the specified ReadGraph. The returned\r
+     * ReadGraph does not accumulate query dependencies into the requests\r
+     * performed with the specified ReadGraph. DB listeners are therefore not\r
+     * triggered by anything that is performed with the returned ReadGraph.\r
+     * \r
+     * @param graph read transaction handle to clone for listener-independent\r
+     *        use\r
+     * @return read transaction handle that is independent of the requests\r
+     *         performed with the parameter\r
+     */\r
+    ReadGraph getIndependentGraph(ReadGraph graph);\r
+    boolean hasParentRequest(ReadGraph graph);\r
+\r
+}\r