/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2000, 2015 Oracle and/or its affiliates. All rights reserved.
*
*/
package com.sleepycat.collections;
import java.util.Comparator;
import java.util.Map;
import java.util.SortedSet;
import com.sleepycat.util.RuntimeExceptionWrapper;
/**
* The SortedSet returned by Map.entrySet(). This class may not be
* instantiated directly. Contrary to what is stated by {@link Map#entrySet}
* this class does support the {@link #add} and {@link #addAll} methods.
*
* <p>The {@link java.util.Map.Entry#setValue} method of the Map.Entry objects
* that are returned by this class and its iterators behaves just as the {@link
* StoredIterator#set} method does.</p>
*
* <p>In addition to the standard SortedSet methods, this class provides the
* following methods for stored sorted sets only. Note that the use of these
* methods is not compatible with the standard Java collections interface.</p>
* <ul>
* <li>{@link #headSet(Map.Entry, boolean)}</li>
* <li>{@link #tailSet(Map.Entry, boolean)}</li>
* <li>{@link #subSet(Map.Entry, boolean, Map.Entry, boolean)}</li>
* </ul>
*
* @author Mark Hayes
*/
public class StoredSortedEntrySet<K, V>
extends StoredEntrySet<K, V>
implements SortedSet<Map.Entry<K, V>> {
StoredSortedEntrySet(DataView mapView) {
super(mapView);
}
/**
* Returns null since comparators are not supported. The natural ordering
* of a stored collection is data byte order, whether the data classes
* implement the {@link java.lang.Comparable} interface or not.
* This method does not conform to the {@link SortedSet#comparator}
* interface.
*
* @return null.
*/
public Comparator<? super Map.Entry<K, V>> comparator() {
return null;
}
/**
* Returns the first (lowest) element currently in this sorted set.
* This method conforms to the {@link SortedSet#first} interface.
*
* @return the first element.
*
*
* @throws RuntimeExceptionWrapper if a checked exception is thrown,
* including a {@code DatabaseException} on BDB (C edition).
*/
public Map.Entry<K, V> first() {
return getFirstOrLast(true);
}
/**
* Returns the last (highest) element currently in this sorted set.
* This method conforms to the {@link SortedSet#last} interface.
*
* @return the last element.
*
*
* @throws RuntimeExceptionWrapper if a checked exception is thrown,
* including a {@code DatabaseException} on BDB (C edition).
*/
public Map.Entry<K, V> last() {
return getFirstOrLast(false);
}
/**
* Returns a view of the portion of this sorted set whose elements are
* strictly less than toMapEntry.
* This method conforms to the {@link SortedSet#headSet} interface.
*
* <p>Note that the return value is a StoredCollection and must be treated
* as such; for example, its iterators must be explicitly closed.</p>
*
* @param toMapEntry the upper bound.
*
* @return the subset.
*
* @throws RuntimeExceptionWrapper if a checked exception is thrown,
* including a {@code DatabaseException} on BDB (C edition).
*/
public SortedSet<Map.Entry<K, V>> headSet(Map.Entry<K, V> toMapEntry) {
return subSet(null, false, toMapEntry, false);
}
/**
* Returns a view of the portion of this sorted set whose elements are
* strictly less than toMapEntry, optionally including toMapEntry.
* This method does not exist in the standard {@link SortedSet} interface.
*
* <p>Note that the return value is a StoredCollection and must be treated
* as such; for example, its iterators must be explicitly closed.</p>
*
* @param toMapEntry is the upper bound.
*
* @param toInclusive is true to include toMapEntry.
*
* @return the subset.
*
* @throws RuntimeExceptionWrapper if a checked exception is thrown,
* including a {@code DatabaseException} on BDB (C edition).
*/
public SortedSet<Map.Entry<K, V>> headSet(Map.Entry<K, V> toMapEntry,
boolean toInclusive) {
return subSet(null, false, toMapEntry, toInclusive);
}
/**
* Returns a view of the portion of this sorted set whose elements are
* greater than or equal to fromMapEntry.
* This method conforms to the {@link SortedSet#tailSet} interface.
*
* <p>Note that the return value is a StoredCollection and must be treated
* as such; for example, its iterators must be explicitly closed.</p>
*
* @param fromMapEntry is the lower bound.
*
* @return the subset.
*
* @throws RuntimeExceptionWrapper if a checked exception is thrown,
* including a {@code DatabaseException} on BDB (C edition).
*/
public SortedSet<Map.Entry<K, V>> tailSet(Map.Entry<K, V> fromMapEntry) {
return subSet(fromMapEntry, true, null, false);
}
/**
* Returns a view of the portion of this sorted set whose elements are
* strictly greater than fromMapEntry, optionally including fromMapEntry.
* This method does not exist in the standard {@link SortedSet} interface.
*
* <p>Note that the return value is a StoredCollection and must be treated
* as such; for example, its iterators must be explicitly closed.</p>
*
* @param fromMapEntry is the lower bound.
*
* @param fromInclusive is true to include fromMapEntry.
*
* @return the subset.
*
* @throws RuntimeExceptionWrapper if a checked exception is thrown,
* including a {@code DatabaseException} on BDB (C edition).
*/
public SortedSet<Map.Entry<K, V>> tailSet(Map.Entry<K, V> fromMapEntry,
boolean fromInclusive) {
return subSet(fromMapEntry, fromInclusive, null, false);
}
/**
* Returns a view of the portion of this sorted set whose elements range
* from fromMapEntry, inclusive, to toMapEntry, exclusive.
* This method conforms to the {@link SortedSet#subSet} interface.
*
* <p>Note that the return value is a StoredCollection and must be treated
* as such; for example, its iterators must be explicitly closed.</p>
*
* @param fromMapEntry is the lower bound.
*
* @param toMapEntry is the upper bound.
*
* @return the subset.
*
* @throws RuntimeExceptionWrapper if a checked exception is thrown,
* including a {@code DatabaseException} on BDB (C edition).
*/
public SortedSet<Map.Entry<K, V>> subSet(Map.Entry<K, V> fromMapEntry,
Map.Entry<K, V> toMapEntry) {
return subSet(fromMapEntry, true, toMapEntry, false);
}
/**
* Returns a view of the portion of this sorted set whose elements are
* strictly greater than fromMapEntry and strictly less than toMapEntry,
* optionally including fromMapEntry and toMapEntry.
* This method does not exist in the standard {@link SortedSet} interface.
*
* <p>Note that the return value is a StoredCollection and must be treated
* as such; for example, its iterators must be explicitly closed.</p>
*
* @param fromMapEntry is the lower bound.
*
* @param fromInclusive is true to include fromMapEntry.
*
* @param toMapEntry is the upper bound.
*
* @param toInclusive is true to include toMapEntry.
*
* @return the subset.
*
* @throws RuntimeExceptionWrapper if a checked exception is thrown,
* including a {@code DatabaseException} on BDB (C edition).
*/
public SortedSet<Map.Entry<K, V>> subSet(Map.Entry<K, V> fromMapEntry,
boolean fromInclusive,
Map.Entry<K, V> toMapEntry,
boolean toInclusive) {
Object fromKey = (fromMapEntry != null) ? fromMapEntry.getKey() : null;
Object toKey = (toMapEntry != null) ? toMapEntry.getKey() : null;
try {
return new StoredSortedEntrySet<K, V>(
view.subView(fromKey, fromInclusive, toKey, toInclusive, null));
} catch (Exception e) {
throw StoredContainer.convertException(e);
}
}
}