/** * 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.hadoop.mapred; import java.io.InputStream; /** * <code>RamManager</code> manages a memory pool of a configured limit. */ interface RamManager { /** * Reserve memory for data coming through the given input-stream. * * @param requestedSize size of memory requested * @param in input stream * @throws InterruptedException * @return <code>true</code> if memory was allocated immediately, * else <code>false</code> */ boolean reserve(int requestedSize, InputStream in) throws InterruptedException; /** * Return memory to the pool. * * @param requestedSize size of memory returned to the pool */ void unreserve(int requestedSize); }