/*
* (C) Copyright 2016 Pantheon Technologies, s.r.o. and others.
*
* 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.opendaylight.yangtools.triemap;
import static org.opendaylight.yangtools.triemap.ImmutableTrieMap.unsupported;
import com.google.common.collect.Iterators;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map.Entry;
/**
* An immutable view of a TrieMap's key set.
*
* @author Robert Varga
*
* @param <K> the type of keys
*/
final class ImmutableKeySet<K> extends AbstractKeySet<K> {
ImmutableKeySet(final TrieMap<K, ?> map) {
super(map);
}
@Override
public Iterator<K> iterator() {
return Iterators.transform(map().immutableIterator(), Entry::getKey);
}
@Override
public void clear() {
throw unsupported();
}
@Override
public boolean remove(final Object o) {
throw unsupported();
}
@Override
public boolean retainAll(final Collection<?> c) {
throw unsupported();
}
@Override
public boolean removeAll(final Collection<?> c) {
throw unsupported();
}
}