    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.pool2;
    018
    019/**
    020 * Provides the possible states that a {@link PooledObject} may be in.
    021 *
    022 * @version $Revision: $
    023 *
    024 * @since 2.0
    025 */
    026public enum PooledObjectState {
    027    /**
    028     * In the queue, not in use.
    029     */
    030    IDLE,
    031
    032    /**
    033     * In use.
    034     */
    035    ALLOCATED,
    036
    037    /**
    038     * In the queue, currently being tested for possible eviction.
    039     */
    040    EVICTION,
    041
    042    /**
    043     * Not in the queue, currently being tested for possible eviction. An
    044     * attempt to borrow the object was made while being tested which removed it
    045     * from the queue. It should be returned to the head of the queue once
    046     * eviction testing completes.
    047     * TODO: Consider allocating object and ignoring the result of the eviction
    048     *       test.
    049     */
    050    EVICTION_RETURN_TO_HEAD,
    051
    052    /**
    053     * In the queue, currently being validated.
    054     */
    055    VALIDATION,
    056
    057    /**
    058     * Not in queue, currently being validated. The object was borrowed while
    059     * being validated and since testOnBorrow was configured, it was removed
    060     * from the queue and pre-allocated. It should be allocated once validation
    061     * completes.
    062     */
    063    VALIDATION_PREALLOCATED,
    064
    065    /**
    066     * Not in queue, currently being validated. An attempt to borrow the object
    067     * was made while previously being tested for eviction which removed it from
    068     * the queue. It should be returned to the head of the queue once validation
    069     * completes.
    070     */
    071    VALIDATION_RETURN_TO_HEAD,
    072
    073    /**
    074     * Failed maintenance (e.g. eviction test or validation) and will be / has
    075     * been destroyed
    076     */
    077    INVALID,
    078
    079    /**
    080     * Deemed abandoned, to be invalidated.
    081     */
    082    ABANDONED,
    083
    084    /**
    085     * Returning to the pool.
    086     */
    087    RETURNING
    088}