/*
* ====================================================================
* 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.http.pool;
import java.util.concurrent.Future;
import org.apache.http.concurrent.FutureCallback;
/**
* {@code ConnPool} represents a shared pool connections can be leased from
* and released back to.
*
* @param <T> the route type that represents the opposite endpoint of a pooled
* connection.
* @param <E> the type of the pool entry containing a pooled connection.
* @since 4.2
*/
public interface ConnPool<T, E> {
/**
* Attempts to lease a connection for the given route and with the given
* state from the pool.
*
* @param route route of the connection.
* @param state arbitrary object that represents a particular state
* (usually a security principal or a unique token identifying
* the user whose credentials have been used while establishing the connection).
* May be {@code null}.
* @param callback operation completion callback.
*
* @return future for a leased pool entry.
*/
Future<E> lease(final T route, final Object state, final FutureCallback<E> callback);
/**
* Releases the pool entry back to the pool.
*
* @param entry pool entry leased from the pool
* @param reusable flag indicating whether or not the released connection
* is in a consistent state and is safe for further use.
*/
void release(E entry, boolean reusable);
}