svn commit: r823327 - /incubator/olio/workload/java/trunk/src/org/apache/olio/workload/loader/framework/LoadablePool.java

[kl...@apache.org]

Author: klichong
Date: Thu Oct  8 21:16:55 2009
New Revision: 823327

URL: http://svn.apache.org/viewvc?rev=823327&view=rev
Log:
fixing build problem for OLIO-133


Added:
    incubator/olio/workload/java/trunk/src/org/apache/olio/workload/loader/framework/LoadablePool.java

Added: incubator/olio/workload/java/trunk/src/org/apache/olio/workload/loader/framework/LoadablePool.java
URL: http://svn.apache.org/viewvc/incubator/olio/workload/java/trunk/src/org/apache/olio/workload/loader/framework/LoadablePool.java?rev=823327&view=auto
==============================================================================
--- incubator/olio/workload/java/trunk/src/org/apache/olio/workload/loader/framework/LoadablePool.java (added)
+++ incubator/olio/workload/java/trunk/src/org/apache/olio/workload/loader/framework/LoadablePool.java Thu Oct  8 21:16:55 2009
@@ -0,0 +1,78 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * $Id$
+ */
+package org.apache.olio.workload.loader.framework;
+
+import java.util.concurrent.LinkedBlockingDeque;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+/**
+ *
+ * @author akara
+ */
+public class LoadablePool<T extends Loadable> {
+
+    private static Logger logger = Logger.getLogger(LoadablePool.class.getName());
+    LinkedBlockingDeque<T> pool = new LinkedBlockingDeque<T>();
+    int sequence;
+    int count = 0;
+    int size;
+    Class<T> clazz;
+
+    public LoadablePool(int size, Class<T> clazz) {
+        this.size = size;
+        this.clazz = clazz;
+    }
+
+    public T getLoadable() throws Exception {
+        T loadable = pool.poll();
+        if (loadable == null) {
+            if (count < size) {
+                loadable = clazz.newInstance();
+                loadable.pool = this;
+                ++count;
+            } else {
+                for (;;) {
+                    try {
+                        loadable = pool.take();
+                        break;
+                    } catch (InterruptedException ex) {
+                        logger.log(Level.WARNING, "getLoader interrupted", ex);
+                    }
+                }
+            }
+        }
+        loadable.sequence = sequence++;
+        return loadable;
+    }
+
+    @SuppressWarnings("unchecked")
+    public void putLoader(Loadable loadable) {
+        for (;;) {
+            try {
+                // User a LIFO model to keep the hot objects in cache.
+                pool.putFirst((T) loadable);
+                break;
+            } catch (InterruptedException ex) {
+                logger.log(Level.WARNING, "putLoader interrupted!", ex);
+            }
+        }
+    }
+}