CollectionsConverter.java

/*
 * #%L
 * Nazgul Project: nazgul-core-reflection-api
 * %%
 * Copyright (C) 2010 - 2017 jGuru Europe AB
 * %%
 * Licensed under the jGuru Europe AB license (the "License"), based
 * on Apache License, Version 2.0; you may not use this file except
 * in compliance with the License.
 *
 * You may obtain a copy of the License at
 *
 *      http://www.jguru.se/licenses/jguruCorporateSourceLicense-2.0.txt
 *
 * 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.
 * #L%
 *
 */

package se.jguru.nazgul.core.reflection.api.conversion.registry.helpers;

import se.jguru.nazgul.core.algorithms.api.collections.predicate.Tuple;
import se.jguru.nazgul.core.reflection.api.conversion.Converter;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
 * @author <a href="mailto:lj@jguru.se">Lennart Jörelid</a>, jGuru Europe AB
 */
public class CollectionsConverter {

    @Converter
    public <T> List<T> convertToList(final Collection<T> collection) {

        // Are we already a List?
        if (collection instanceof List) {
            return (List<T>) collection;
        }

        // Not an inbound List. Wrap and return.
        List<T> toReturn = new ArrayList<T>();
        toReturn.addAll(collection);
        return toReturn;
    }

    @Converter
    @SuppressWarnings({"unchecked", "rawtypes"})
    public List convertSetToList(final Set set) {

        final List toReturn = new ArrayList();
        toReturn.add("convertSetToList");
        toReturn.addAll(set);
        return toReturn;
    }

    @Converter
    public <K, V> List<Tuple<K, V>> convertToList(final Map<K, V> map) {

        List<Tuple<K, V>> toReturn = new ArrayList<Tuple<K, V>>();
        for (Map.Entry<K, V> current : map.entrySet()) {
            toReturn.add(new Tuple<K, V>(current.getKey(), current.getValue()));
        }

        return toReturn;
    }
}