001// Copyright 2004, 2005 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry.services;
016
017import org.apache.tapestry.engine.IEngineService;
018
019/**
020 * Service interface for <code>tapestry.services.ServiceMap</code>, provides access to engine
021 * services defined in the HiveMind module deployment descriptors.
022 * <p>
023 * Note: In Tapestry 3.0 and earlier, a &lt;service&gt; element in the application and library
024 * specifications was used to define services. This is no longer supported.
025 * 
026 * @author Howard Lewis Ship
027 * @since 4.0
028 */
029public interface ServiceMap
030{
031    /**
032     * Returns the named service.
033     * 
034     * @param name
035     *            the unique name for the service, as defined by each service instance's
036     *            {@link IEngineService#getName()} method.
037     * @returns the named service
038     * @throws org.apache.hivemind.ApplicationRuntimeException
039     *             if the named service does not exist
040     */
041    public IEngineService getService(String name);
042
043    /**
044     * Returns true if the name is a known service, or false otherwise.
045     */
046
047    public boolean isValid(String name);
048}