1 /* 2 * ==================================================================== 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, 14 * software distributed under the License is distributed on an 15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16 * KIND, either express or implied. See the License for the 17 * specific language governing permissions and limitations 18 * under the License. 19 * ==================================================================== 20 * 21 * This software consists of voluntary contributions made by many 22 * individuals on behalf of the Apache Software Foundation. For more 23 * information on the Apache Software Foundation, please see 24 * <http://www.apache.org/>. 25 * 26 */ 27 package org.apache.http.pool; 28 29 import java.util.concurrent.Future; 30 31 import org.apache.http.concurrent.FutureCallback; 32 33 /** 34 * {@code ConnPool} represents a shared pool connections can be leased from 35 * and released back to. 36 * 37 * @param <T> the route type that represents the opposite endpoint of a pooled 38 * connection. 39 * @param <E> the type of the pool entry containing a pooled connection. 40 * @since 4.2 41 */ 42 public interface ConnPool<T, E> { 43 44 /** 45 * Attempts to lease a connection for the given route and with the given 46 * state from the pool. 47 * 48 * @param route route of the connection. 49 * @param state arbitrary object that represents a particular state 50 * (usually a security principal or a unique token identifying 51 * the user whose credentials have been used while establishing the connection). 52 * May be {@code null}. 53 * @param callback operation completion callback. 54 * 55 * @return future for a leased pool entry. 56 */ 57 Future<E> lease(final T route, final Object state, final FutureCallback<E> callback); 58 59 /** 60 * Releases the pool entry back to the pool. 61 * 62 * @param entry pool entry leased from the pool 63 * @param reusable flag indicating whether or not the released connection 64 * is in a consistent state and is safe for further use. 65 */ 66 void release(E entry, boolean reusable); 67 68 }