dependencymanager/runtime/src/main/java/org/apache/felix/dm/runtime/AbstractBuilder.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.felix.dm.runtime;

import java.util.List;

import org.apache.felix.dm.Component;
import org.apache.felix.dm.Dependency;
import org.apache.felix.dm.DependencyManager;
import org.osgi.framework.Bundle;

/**
 * Base class for all kind of DM component builders (for Component, Aspect, Adapters ...).
 * 
 * @author <a href="mailto:dev@felix.apache.org">Felix Project Team</a>
 */
public abstract class AbstractBuilder
{
    /**
     * Returns the service component type.
     */
    abstract String getType();

    /**
     * Builds the service component.
     * @param serviceMetaData the service component metadata parsed from the descriptor file.
     * @param serviceDependencies the service component dependencies metadata parsed from the descriptor file.
     */
    abstract void build(MetaData serviceMetaData, List<MetaData> serviceDependencies, Bundle b,
        DependencyManager dm)
        throws Exception;

    /**
     * Sets common Service parameters, if provided from our Component descriptor
     */
    protected void setCommonServiceParams(Component service, MetaData serviceMetaData)
        throws Exception
    {
        String init = serviceMetaData.getString(Params.init, null);
        String start = serviceMetaData.getString(Params.start, null);
        String stop = serviceMetaData.getString(Params.stop, null);
        String destroy = serviceMetaData.getString(Params.destroy, null);
        service.setCallbacks(init, start, stop, destroy);
        String composition = serviceMetaData.getString(Params.composition, null);
        if (composition != null)
        {
            service.setComposition(composition);
        }
    }
    
    /**
     * Registers all unnamed dependencies into a given service. Named dependencies are
     * handled differently, and are managed by the ServiceLifecycleHandler class.
     * @throws Exception 
     */
    protected static void addUnamedDependencies(Bundle b, DependencyManager dm, Component s, 
                                                MetaData srvMeta, List<MetaData> depsMeta) 
        throws Exception
    {
        for (MetaData dependency : depsMeta) 
        {
            String name = dependency.getString(Params.name, null);
            if (name == null) {
                DependencyBuilder depBuilder = new DependencyBuilder(dependency);
                Log.instance().info("ServiceLifecycleHandler.init: adding dependency %s into service %s",
                                   dependency, srvMeta);
                Dependency d = depBuilder.build(b, dm, false);
                s.add(d);
            }
        }
    }
}