PersistentMap.java

/*
 * Copyright 2013 Samppa Saarela
 *
 * Licensed 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.javersion.util;

import java.util.Map;
import java.util.Map.Entry;
import java.util.Spliterator;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;

import javax.annotation.concurrent.Immutable;

import com.google.common.collect.Iterables;

@Immutable
public interface PersistentMap<K, V> extends Iterable<Entry<K, V>> {

    PersistentMap<K, V> assoc(K key, V value);

    PersistentMap<K, V> assocAll(Map<? extends K, ? extends V> map);

    PersistentMap<K, V> assocAll(Iterable<Entry<K, V>> entries);

    PersistentMap<K, V> merge(K key, V value, Merger<Entry<K, V>> merger);

    PersistentMap<K, V> mergeAll(Map<? extends K, ? extends V> map, Merger<Entry<K, V>> merger);

    PersistentMap<K, V> mergeAll(Iterable<Entry<K, V>> entries, Merger<Entry<K, V>> merger);

    PersistentMap<K, V> dissoc(Object key);

    PersistentMap<K, V> dissoc(Object key, Merger<Entry<K, V>> merger);

    V get(Object key);

    boolean containsKey(Object key);

    Spliterator<Entry<K, V>> spliterator();

    Spliterator<K> keySpliterator();

    Spliterator<V> valueSpliterator();

    int size();

    boolean isEmpty();

    MutableMap<K, V> toMutableMap();

    Map<K, V> asMap();

    default Iterable<K> keys() {
        return Iterables.transform(this, MapUtils.<K>mapKeyFunction());
    }

    default Iterable<V> values() {
        return Iterables.transform(this, MapUtils.<V>mapValueFunction());
    }

    default Stream<Entry<K, V>> stream() {
        return StreamSupport.stream(spliterator(), false);
    }

    default Stream<Entry<K, V>> parallelStream() {
        return StreamSupport.stream(spliterator(), true);
    }

    default Stream<K> keyStream() {
        return StreamSupport.stream(keySpliterator(), false);
    }

    default Stream<K> parallelKeyStream() {
        return StreamSupport.stream(keySpliterator(), true);
    }

    default Stream<V> valueStream() {
        return StreamSupport.stream(valueSpliterator(), false);
    }

    default Stream<V> parallelValueStream() {
        return StreamSupport.stream(valueSpliterator(), true);
    }

}