/*
* Copyright 2002-2016 the original author or authors.
*
* Licensed 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.springframework.integration.util;
/**
* Represents a pool of items.
* @author Gary Russell
* @since 2.2
*
*/
public interface Pool<T> {
/**
* Obtains an item from the pool.
* @return the item.
*/
T getItem();
/**
* Releases an item back into the pool. This must be an item that
* was previously retrieved using {@link #getItem()}.
* @param t the item.
* @throws IllegalArgumentException when a "foreign" object
* is released.
*/
void releaseItem(T t);
/**
* Removes all idle items from the pool.
*/
void removeAllIdleItems();
/**
* Returns the current size (limit) of the pool.
* @return the size.
*/
int getPoolSize();
/**
* Returns the number of items that have been allocated
* but are not currently in use.
* @return The number of items.
*/
int getIdleCount();
/**
* Returns the number of allocated items that are currently
* checked out of the pool.
* @return The number of items.
*/
int getActiveCount();
/**
* Returns the current count of allocated items (in use and
* idle). May be less than the pool size, and reflects the
* high water mark of pool usage.
* @return the number of items.
*/
int getAllocatedCount();
}