libcore/luni/src/main/java/org/apache/harmony/luni/platform/AdapterManager.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.harmony.luni.platform;


import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;

/**
 * Adapter Manager
 *  
 */
final class AdapterManager implements IAdapterManager {

    /*
     * key is adaptable type, and value is list of adapter factories for that
     * type.
     */
    private final HashMap<Class, List<IAdapterFactory>> factories = new HashMap<Class, List<IAdapterFactory>>();

    public Object getAdapter(IAdaptable adaptable, Class adapterType) {
        List factoryList = factories.get(adapterType);
        if (factoryList != null) {
            for (Iterator factoryItr = factoryList.iterator(); factoryItr
                    .hasNext();) {
                IAdapterFactory factory = (IAdapterFactory) factoryItr.next();
                Object adapter = factory.getAdapter(adaptable, adapterType);
                if (adapter != null) {
                    return adapter;
                }
            }
        }
        return null;
    }

    public boolean hasAdapter(IAdaptable adaptable, Class adapterType) {
        return null == getAdapter(adaptable, adapterType);
    }

    public void registerAdapters(IAdapterFactory factory, Class adaptable) {
        List<IAdapterFactory> factoryList = factories.get(adaptable);
        if (factoryList == null) {
            factoryList = new ArrayList<IAdapterFactory>();
            factories.put(adaptable, factoryList);
        }
        factoryList.add(factory);
    }

    public void unregisterAdapters(IAdapterFactory factory, Class adaptable) {
        List factoryList = factories.get(adaptable);
        if (factoryList != null) {
            factoryList.remove(factory);
        }
    }

    public void unregisterAdapters(IAdapterFactory factory) {
        for (Iterator<Class> knownAdaptablesItr = factories.keySet().iterator(); knownAdaptablesItr
                .hasNext();) {
            Class adaptable = knownAdaptablesItr.next();
            unregisterAdapters(factory, adaptable);
        }
    }
}