/*
 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Oracle or the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package dictionary;

import dictionary.spi.Dictionary;
import java.util.Iterator;
import java.util.ServiceConfigurationError;
import java.util.ServiceLoader;

public class DictionaryService {

    private static DictionaryService service;
    private ServiceLoader<Dictionary> loader;

    private DictionaryService() {
        loader = ServiceLoader.load(Dictionary.class);
    }

    public static synchronized DictionaryService getInstance() {
        if (service == null) {
            service = new DictionaryService();
        }
        return service;
    }


    public String getDefinition(String word) {
        String definition = null;

        try {
            Iterator<Dictionary> dictionaries = loader.iterator();
            while (definition == null && dictionaries.hasNext()) {
                Dictionary d = dictionaries.next();
                definition = d.getDefinition(word);
            }
        } catch (ServiceConfigurationError serviceError) {
            definition = null;
            serviceError.printStackTrace();

        }
        return definition;
    }
}