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 * 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
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package org.apache.commons.collections4;

Defines a map that allows bidirectional lookup between key and values
and retains and provides access to an ordering.

Implementations should allow a value to be looked up from a key and
a key to be looked up from a value with equal performance.

Type parameters:
<K> – the type of the keys in the map
<V> – the type of the values in the map
Since:
3.0/**
 * Defines a map that allows bidirectional lookup between key and values
 * and retains and provides access to an ordering.
 * <p>
 * Implementations should allow a value to be looked up from a key and
 * a key to be looked up from a value with equal performance.
 * </p>
 *
 * @param <K> the type of the keys in the map
 * @param <V> the type of the values in the map
 *
 * @since 3.0
 */
public interface OrderedBidiMap<K, V> extends BidiMap<K, V>, OrderedMap<K, V> {

    
Gets a view of this map where the keys and values are reversed.

Changes to one map will be visible in the other and vice versa.
This enables both directions of the map to be accessed equally.

Implementations should seek to avoid creating a new object every time this
method is called. See AbstractMap.values() etc. Calling this
method on the inverse map should return the original.

Implementations must return an OrderedBidiMap instance,
usually by forwarding to inverseOrderedBidiMap().
Returns:
an inverted bidirectional map/**
     * Gets a view of this map where the keys and values are reversed.
     * <p>
     * Changes to one map will be visible in the other and vice versa.
     * This enables both directions of the map to be accessed equally.
     * <p>
     * Implementations should seek to avoid creating a new object every time this
     * method is called. See <code>AbstractMap.values()</code> etc. Calling this
     * method on the inverse map should return the original.
     * <p>
     * Implementations must return an <code>OrderedBidiMap</code> instance,
     * usually by forwarding to <code>inverseOrderedBidiMap()</code>.
     *
     * @return an inverted bidirectional map
     */
    @Override
    OrderedBidiMap<V, K> inverseBidiMap();

}