libraries/spring/src/main/java/org/apache/zest/library/spring/importer/SpringImporter.java

/*
 * Copyright (c) 2008, Rickard Öberg. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package org.apache.zest.library.spring.importer;

import org.apache.zest.api.service.ImportedServiceDescriptor;
import org.apache.zest.api.service.ServiceImporter;
import org.apache.zest.api.service.ServiceImporterException;
import org.springframework.context.ApplicationContext;

/**
 * Import a service from Spring. This assumes that the service has been imported
 * into the assembly using the SpringImporterAssembler, so that the ApplicationContext
 * is available as service meta-info.
 */
public class SpringImporter
    implements ServiceImporter
{
    /**
     * Import a service from Spring by looking it up in the ApplicationContext.
     *
     * @param serviceDescriptor The service descriptor.
     * @return a service instance
     * @throws ServiceImporterException if unable to import the service
     */
    @Override
    public Object importService( ImportedServiceDescriptor serviceDescriptor ) throws ServiceImporterException
    {
        try
        {
            return serviceDescriptor.
                metaInfo( ApplicationContext.class ).
                getBean( serviceDescriptor.identity(), serviceDescriptor.type() );
        }
        catch( Throwable e )
        {
            throw new ServiceImporterException( "Could not import Spring service with id " + serviceDescriptor.identity(), e );
        }
    }

    @Override
    public boolean isAvailable( Object instance )
    {
        return true;
    }
}