| /* |
| * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//pool/src/java/org/apache/commons/pool/KeyedObjectPool.java,v 1.1 2001/04/14 16:40:43 rwaldhoff Exp $ |
| * $Revision: 1.1 $ |
| * $Date: 2001/04/14 16:40:43 $ |
| * |
| * ==================================================================== |
| * |
| * The Apache Software License, Version 1.1 |
| * |
| * Copyright (c) 1999-2001 The Apache Software Foundation. All rights |
| * reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The end-user documentation included with the redistribution, if |
| * any, must include the following acknowlegement: |
| * "This product includes software developed by the |
| * Apache Software Foundation (http://www.apache.org/)." |
| * Alternately, this acknowlegement may appear in the software itself, |
| * if and wherever such third-party acknowlegements normally appear. |
| * |
| * 4. The names "The Jakarta Project", "Commons", and "Apache Software |
| * Foundation" must not be used to endorse or promote products derived |
| * from this software without prior written permission. For written |
| * permission, please contact apache@apache.org. |
| * |
| * 5. Products derived from this software may not be called "Apache" |
| * nor may "Apache" appear in their names without prior written |
| * permission of the Apache Group. |
| * |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * 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.commons.pool; |
| |
| /** |
| * A simple "keyed" {@link Object} pooling interface. |
| * <p> |
| * A keyed pool caches mutiple named instances of {@link Object}s. |
| * <p> |
| * Example of use: |
| * <table border="1" cellspacing="0" cellpadding="3" align="center" bgcolor="#FFFFFF"><tr><td><pre> |
| * Object obj = <font color="#0000CC">null</font>; |
| * Object key = <font color="#CC0000">"Key"</font>; |
| * <font color="#0000CC">try</font> { |
| * obj = keyedPool.borrowObject(key); |
| * <font color="#00CC00">//...use the object...</font> |
| * } <font color="#0000CC">catch</font>(Exception e) { |
| * <font color="#00CC00">//...handle any exceptions...</font> |
| * } <font color="#0000CC">finally</font> { |
| * <font color="#00CC00">// make sure the object is returned to the pool</font> |
| * <font color="#0000CC">if</font>(<font color="#0000CC">null</font> != obj) { |
| * keyedPool.returnObject(key,obj); |
| * } |
| * }</pre></td></tr></table> |
| * |
| * <p> |
| * {@link KeyedObjectPool} implementations <i>may</i> choose to store at most |
| * one instance per key value, or may choose to maintain a pool of instances |
| * for each key (essentially creating a Map of Pools). |
| * </p> |
| * |
| * @author Rodney Waldhoff |
| * @version $Id: KeyedObjectPool.java,v 1.1 2001/04/14 16:40:43 rwaldhoff Exp $ |
| * |
| * @see KeyedPoolableObjectFactory |
| * @see KeyedObjectPoolFactory |
| * @see ObjectPool |
| */ |
| public interface KeyedObjectPool { |
| /** |
| * Obtain an <tt>Object</tt> from my pool |
| * using the specified <i>key</i>. |
| * By contract, clients MUST return |
| * the borrowed object using |
| * {@link #returnObject(java.lang.Object,java.lang.Object) <tt>returnObject</tt>}, |
| * or a related method as defined in an implementation |
| * or sub-interface, |
| * using a <i>key</i> that is equivalent to the one used to |
| * borrow the <tt>Object</tt> in the first place. |
| * |
| * @param key the key used to obtain the object |
| * @return an <tt>Object</tt> from my pool. |
| */ |
| public abstract Object borrowObject(Object key); |
| |
| /** |
| * Return an <tt>Object</tt> to my pool. |
| * By contract, <i>obj</i> MUST have been obtained |
| * using {@link #borrowObject(java.lang.Object) <tt>borrowObject</tt>} |
| * or a related method as defined in an implementation |
| * or sub-interface, |
| * using a <i>key</i> that is equivalent to the one used to |
| * borrow the <tt>Object</tt> in the first place. |
| * |
| * @param key the key used to obtain the object |
| * @param obj a {@link #borrowObject(java.lang.Object) borrowed} <tt>Object</tt> to be returned. |
| */ |
| public abstract void returnObject(Object key, Object obj); |
| |
| /** |
| * Return the number of <tt>Object</tt>s |
| * corresponding to the given <i>key</i> |
| * currently idle in my pool, or |
| * throws {@link UnsupportedOperationException} |
| * if this information is not available. |
| * |
| * @param key the key |
| * @return the number of <tt>Object</tt>s corresponding to the given <i>key</i> currently idle in my pool |
| * @throws UnsupportedOperationException |
| */ |
| public abstract int numIdle(Object key) throws UnsupportedOperationException; |
| |
| /** |
| * Return the number of <tt>Object</tt>s |
| * currently borrowed from my pool corresponding to the |
| * given <i>key</i>, or |
| * throws {@link UnsupportedOperationException} |
| * if this information is not available. |
| * |
| * @param key the key |
| * @return the number of <tt>Object</tt>s corresponding to the given <i>key</i> currently borrowed in my pool |
| * @throws UnsupportedOperationException |
| */ |
| public abstract int numActive(Object key) throws UnsupportedOperationException; |
| |
| /** |
| * Return the total number of <tt>Object</tt>s |
| * currently idle in my pool, or |
| * throws {@link UnsupportedOperationException} |
| * if this information is not available. |
| * |
| * @return the total number of <tt>Object</tt>s currently idle in my pool |
| * @throws UnsupportedOperationException |
| */ |
| public abstract int numIdle() throws UnsupportedOperationException; |
| |
| /** |
| * Return the total number of <tt>Object</tt>s |
| * current borrowed from my pool, or |
| * throws {@link UnsupportedOperationException} |
| * if this information is not available. |
| * |
| * @return the total number of <tt>Object</tt>s currently borrowed in my pool |
| * @throws UnsupportedOperationException |
| */ |
| public abstract int numActive() throws UnsupportedOperationException; |
| |
| /** |
| * Clears my pool, or throws {@link UnsupportedOperationException} |
| * if the pool cannot be cleared. |
| */ |
| public abstract void clear() throws UnsupportedOperationException; |
| |
| /** |
| * Clears the specified pool, or throws {@link UnsupportedOperationException} |
| * if the pool cannot be cleared. |
| * @param key the key to clear |
| */ |
| public abstract void clear(Object key) throws UnsupportedOperationException; |
| |
| /** |
| * Close this pool, and free any resources associated with it. |
| */ |
| public abstract void close(); |
| |
| /** |
| * Sets the {@link KeyedPoolableObjectFactory factory} I use |
| * to create new instances. |
| * @param factory the {@link KeyedPoolableObjectFactory} I use to create new instances. |
| */ |
| public abstract void setFactory(KeyedPoolableObjectFactory factory) throws IllegalStateException, UnsupportedOperationException; |
| } |