it.unimi.dsi.fastutil.objects.AbstractReference2ReferenceSortedMap Maven / Gradle / Ivy
/*
* Copyright (C) 2002-2022 Sebastiano Vigna
*
* 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 it.unimi.dsi.fastutil.objects;
import java.util.Comparator;
/** An abstract class providing basic methods for sorted maps implementing a type-specific interface. */
public abstract class AbstractReference2ReferenceSortedMap extends AbstractReference2ReferenceMap implements Reference2ReferenceSortedMap {
private static final long serialVersionUID = -1773560792952436569L;
protected AbstractReference2ReferenceSortedMap() {}
/** {@inheritDoc}
*
* The view is backed by the sorted set returned by {@link java.util.Map#entrySet()}. Note that
* no attempt is made at caching the result of this method, as this would
* require adding some attributes that lightweight implementations would
* not need. Subclasses may easily override this policy by calling
* this method and caching the result, but implementors are encouraged to
* write more efficient ad-hoc implementations.
*
* @return a sorted set view of the keys of this map; it may be safely cast to a type-specific interface.
*/
@Override
public ReferenceSortedSet keySet() {
return new KeySet();
}
/** A wrapper exhibiting the keys of a map. */
protected class KeySet extends AbstractReferenceSortedSet {
@Override
public boolean contains(final Object k) { return containsKey(k); }
@Override
public int size() { return AbstractReference2ReferenceSortedMap.this.size(); }
@Override
public void clear() { AbstractReference2ReferenceSortedMap.this.clear(); }
@Override
public Comparator comparator() { return AbstractReference2ReferenceSortedMap.this.comparator(); }
@Override
public K first() { return firstKey(); }
@Override
public K last() { return lastKey(); }
@Override
public ReferenceSortedSet headSet(final K to) { return headMap(to).keySet(); }
@Override
public ReferenceSortedSet tailSet(final K from) { return tailMap(from).keySet(); }
@Override
public ReferenceSortedSet subSet(final K from, final K to) { return subMap(from, to).keySet(); }
@Override
public ObjectBidirectionalIterator iterator(final K from) { return new KeySetIterator <>(reference2ReferenceEntrySet().iterator(new BasicEntry <>(from, (null)))); }
@Override
public ObjectBidirectionalIterator iterator() { return new KeySetIterator <>(Reference2ReferenceSortedMaps.fastIterator(AbstractReference2ReferenceSortedMap.this)); }
}
/** A wrapper exhibiting a map iterator as an iterator on keys.
*
* To provide an iterator on keys, just create an instance of this
* class using the corresponding iterator on entries.
*/
protected static class KeySetIterator implements ObjectBidirectionalIterator {
protected final ObjectBidirectionalIterator > i;
public KeySetIterator(ObjectBidirectionalIterator > i) {
this.i = i;
}
@Override
public K next() { return i.next().getKey(); };
@Override
public K previous() { return i.previous().getKey(); };
@Override
public boolean hasNext() { return i.hasNext(); }
@Override
public boolean hasPrevious() { return i.hasPrevious(); }
}
/** {@inheritDoc}
*
* The view is backed by the sorted set returned by {@link java.util.Map#entrySet()}. Note that
* no attempt is made at caching the result of this method, as this would
* require adding some attributes that lightweight implementations would
* not need. Subclasses may easily override this policy by calling
* this method and caching the result, but implementors are encouraged to
* write more efficient ad-hoc implementations.
*
* @return a type-specific collection view of the values contained in this map.
*/
@Override
public ReferenceCollection values() {
return new ValuesCollection();
}
/** A wrapper exhibiting the values of a map. */
protected class ValuesCollection extends AbstractReferenceCollection {
@Override
public ObjectIterator iterator() { return new ValuesIterator <>(Reference2ReferenceSortedMaps.fastIterator(AbstractReference2ReferenceSortedMap.this)); }
@Override
public boolean contains(final Object k) { return containsValue(k); }
@Override
public int size() { return AbstractReference2ReferenceSortedMap.this.size(); }
@Override
public void clear() { AbstractReference2ReferenceSortedMap.this.clear(); }
}
/** A wrapper exhibiting a map iterator as an iterator on values.
*
* To provide an iterator on values, just create an instance of this
* class using the corresponding iterator on entries.
*/
protected static class ValuesIterator implements ObjectIterator {
protected final ObjectBidirectionalIterator > i;
public ValuesIterator(ObjectBidirectionalIterator > i) {
this.i = i;
}
@Override
public V next() { return i.next().getValue(); };
@Override
public boolean hasNext() { return i.hasNext(); }
}
}