| /* |
| * 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. |
| */ |
| |
| package org.apache.activemq.artemis.jlibaio.util; |
| |
| import org.apache.activemq.artemis.jlibaio.SubmitInfo; |
| |
| /** |
| * this is an utility class where you can reuse Callbackk objects for your LibaioContext usage. |
| */ |
| public class CallbackCache<Callback extends SubmitInfo> { |
| |
| private final SubmitInfo[] pool; |
| |
| private int put = 0; |
| private int get = 0; |
| private int available = 0; |
| private final int size; |
| |
| private final Object lock = new Object(); |
| |
| public CallbackCache(int size) { |
| this.pool = new SubmitInfo[size]; |
| this.size = size; |
| } |
| |
| public Callback get() { |
| synchronized (lock) { |
| if (available <= 0) { |
| return null; |
| } else { |
| Callback retValue = (Callback) pool[get]; |
| pool[get] = null; |
| if (retValue == null) { |
| throw new NullPointerException("You should initialize the pool before using it"); |
| } |
| available--; |
| get++; |
| if (get >= size) { |
| get = 0; |
| } |
| return retValue; |
| } |
| } |
| } |
| |
| public CallbackCache put(Callback callback) { |
| if (callback == null) { |
| return null; |
| } |
| synchronized (lock) { |
| if (available < size) { |
| available++; |
| pool[put++] = callback; |
| if (put >= size) { |
| put = 0; |
| } |
| } |
| } |
| return this; |
| } |
| } |