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.hivemind.lib.factory;
016
017import org.apache.hivemind.ApplicationRuntimeException;
018import org.apache.hivemind.HiveMind;
019import org.apache.hivemind.Location;
020import org.apache.hivemind.internal.Module;
021import org.apache.hivemind.lib.BeanFactory;
022import org.apache.hivemind.service.ObjectProvider;
023
024/**
025 * An {@link org.apache.hivemind.service.ObjectProvider}
026 * that references a named (or named and initialized) bean from a 
027 * {@link org.apache.hivemind.lib.BeanFactory}.  The translator string is of the form:
028 * <code>service-id:name[,initializer]</code>. That is, the text after the colon
029 * is an initializer passed to {@link org.apache.hivemind.lib.BeanFactory#get(String)}.
030 *
031 * @author Howard Lewis Ship
032 */
033public class BeanFactoryObjectProvider implements ObjectProvider
034{
035    public Object provideObject(
036        Module contributingModule,
037        Class propertyType,
038        String inputValue,
039        Location location)
040    {
041        if (HiveMind.isBlank(inputValue))
042            return null;
043
044        int colonx = inputValue.indexOf(':');
045
046        if (colonx < 0)
047            throw new ApplicationRuntimeException(
048                FactoryMessages.invalidBeanTranslatorFormat(inputValue),
049                location,
050                null);
051
052        String serviceId = inputValue.substring(0, colonx);
053
054        if (serviceId.length() == 0)
055            throw new ApplicationRuntimeException(
056                FactoryMessages.invalidBeanTranslatorFormat(inputValue),
057                location,
058                null);
059
060        String locator = inputValue.substring(colonx + 1);
061
062        if (locator.length() == 0)
063            throw new ApplicationRuntimeException(
064                FactoryMessages.invalidBeanTranslatorFormat(inputValue),
065                location,
066                null);
067
068        BeanFactory f = (BeanFactory) contributingModule.getService(serviceId, BeanFactory.class);
069
070        return f.get(locator);
071    }
072
073}