    001// Licensed under the Apache License, Version 2.0 (the "License");
    002// you may not use this file except in compliance with the License.
    003// You may obtain a copy of the License at
    004//
    005//     http://www.apache.org/licenses/LICENSE-2.0
    006//
    007// Unless required by applicable law or agreed to in writing, software
    008// distributed under the License is distributed on an "AS IS" BASIS,
    009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    010// See the License for the specific language governing permissions and
    011// limitations under the License.
    012
    013package org.apache.tapestry5.ioc;
    014
    015
    016/**
    017 * Defines constants for built-in scopes (used with the {@link org.apache.tapestry5.ioc.annotations.Scope} annotation.
    018 */
    019public class ScopeConstants
    020{
    021    /**
    022     * The default scope is a singleton within the {@link org.apache.tapestry5.ioc.Registry}. A single instance will be
    023     * created on demand.  The lifespan of the instance lasts until the registry is {@linkplain Registry#shutdown() shut
    024     * down}. Some implementations will want to know when the Registry is shutdown; they should register for
    025     * notifications via the {@link org.apache.tapestry5.ioc.services.RegistryShutdownHub} service.
    026     */
    027    public static final String DEFAULT = "singleton";
    028
    029    /**
    030     * An alternate scope provided with Tapestry; a per-thread instance is created on demand, behind a shared proxy.
    031     * Method invocations on the shared proxy are forwarded to the per-thread instance. Each per-thread instance lasts
    032     * until the {@linkplain Registry#cleanupThread() thread is cleaned up} (at the end of a request for a web
    033     * application). Some implementations will want to be notified before being discarded and should register with
    034     * the {@link org.apache.tapestry5.ioc.services.PerthreadManager} to receive notifications.
    035     *
    036     * @see org.apache.tapestry5.ioc.internal.services.PerThreadServiceLifecycle
    037     */
    038    public static final String PERTHREAD = "perthread";
    039}