de.xaniox.heavyspleef.core.collection.DualMaps.java Source code

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Here is the source code for de.xaniox.heavyspleef.core.collection.DualMaps.java

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/*
 * This file is part of HeavySpleef.
 * Copyright (c) 2014-2016 Matthias Werning
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
package de.xaniox.heavyspleef.core.collection;

import com.google.common.collect.BiMap;
import com.google.common.collect.ForwardingMap;
import com.google.common.collect.Maps;
import de.xaniox.heavyspleef.core.collection.DualKeyMap.DualKeyPair;
import org.apache.commons.lang.Validate;

import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class DualMaps {

    public static <K1, K2, V> DualKeyBiMap<K1, K2, V> immutableDualBiMap(DualKeyBiMap<K1, K2, V> map) {
        return new ForwardingImmutableDualKeyBiMap<K1, K2, V>(map);
    }

    @SuppressWarnings("unchecked")
    public static <K1, K2, V, MV> DualKeyBiMap<K1, K2, MV> valueMappedImmutableDualBiMap(
            DualKeyBiMap<K1, K2, V> map, Mapper<V, MV> mapper) {
        Validate.notNull(map, "Map cannot be null");
        Validate.notNull(mapper, "Mapper cannot be null");

        Set<Entry<DualKeyPair<K1, K2>, V>> entries = map.entrySet();
        DualKeyBiMap<K1, K2, MV> mappedMap = new DualKeyHashBiMap<K1, K2, MV>(map.getPrimaryKeyClass(),
                map.getSecondaryKeyClass());

        for (Entry<DualKeyPair<K1, K2>, V> entry : entries) {
            V val = entry.getValue();
            MV mapped = mapper.map(val);

            mappedMap.put((DualKeyPair<K1, K2>) entry.getKey().clone(), mapped);
        }

        return immutableDualBiMap(mappedMap);
    }

    public static interface Mapper<F, T> {

        public T map(F from);

    }

    private static final class ForwardingImmutableDualKeyBiMap<K1, K2, V>
            extends ForwardingMap<DualKeyPair<K1, K2>, V> implements DualKeyBiMap<K1, K2, V> {

        private DualKeyBiMap<K1, K2, V> delegate;
        private BiMap<V, DualKeyPair<K1, K2>> inverse;

        public ForwardingImmutableDualKeyBiMap(DualKeyBiMap<K1, K2, V> delegate) {
            this.delegate = delegate;
        }

        @Override
        public Class<K1> getPrimaryKeyClass() {
            return delegate.getPrimaryKeyClass();
        }

        @Override
        public Class<K2> getSecondaryKeyClass() {
            return delegate.getSecondaryKeyClass();
        }

        @Override
        public V put(K1 primaryKey, K2 secondaryKey, V value) {
            throw new UnsupportedOperationException();
        }

        @Override
        public V forcePut(DualKeyPair<K1, K2> key, V value) {
            throw new UnsupportedOperationException();
        }

        @Override
        public Set<V> values() {
            return delegate.values();
        }

        @Override
        public Set<K1> primaryKeySet() {
            return delegate.primaryKeySet();
        }

        @Override
        public Set<K2> secondaryKeySet() {
            return delegate.secondaryKeySet();
        }

        @Override
        public BiMap<V, DualKeyPair<K1, K2>> inverse() {
            return inverse == null ? (inverse = Maps.unmodifiableBiMap(delegate.inverse())) : inverse;
        }

        @Override
        public V forcePut(K1 primaryKey, K2 secondaryKey, V value) {
            throw new UnsupportedOperationException();
        }

        @Override
        protected Map<DualKeyPair<K1, K2>, V> delegate() {
            return delegate;
        }

    }

}