/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2000-2003
* Sleepycat Software. All rights reserved.
*
* $Id: StoredSortedMap.java,v 1.10 2003/10/22 14:28:40 mhayes Exp $
*/
package com.sleepycat.bdb.collection;
import com.sleepycat.bdb.bind.DataBinding;
import com.sleepycat.bdb.bind.EntityBinding;
import com.sleepycat.bdb.DataCursor;
import com.sleepycat.bdb.DataIndex;
import com.sleepycat.bdb.DataStore;
import com.sleepycat.bdb.DataView;
import com.sleepycat.db.Db;
import com.sleepycat.db.DbException;
import java.util.Comparator;
import java.util.SortedMap;
/**
* A SortedMap view of a {@link DataStore} or {@link DataIndex}.
*
* <p>In addition to the standard SortedMap methods, this class provides the
* following methods for stored sorted maps only. Note that the use of these
* methods is not compatible with the standard Java collections interface.</p>
* <ul>
* <li>{@link #duplicates(Object)}</li>
* <li>{@link #headMap(Object, boolean)}</li>
* <li>{@link #tailMap(Object, boolean)}</li>
* <li>{@link #subMap(Object, boolean, Object, boolean)}</li>
* </ul>
*
* @author Mark Hayes
*/
public class StoredSortedMap extends StoredMap implements SortedMap {
/**
* Creates a sorted map view of a {@link DataStore}.
*
* @param store is the DataStore underlying the new collection.
*
* @param keyBinding is the binding used to translate between key buffers
* and key objects.
*
* @param valueBinding is the binding used to translate between value
* buffers and value objects.
*
* @param writeAllowed is true to create a read-write collection or false
* to create a read-only collection.
*
* @throws IllegalArgumentException if formats are not consistently
* defined or a parameter is invalid.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public StoredSortedMap(DataStore store, DataBinding keyBinding,
DataBinding valueBinding, boolean writeAllowed) {
super(new DataView(store, null, keyBinding, valueBinding,
null, writeAllowed));
}
/**
* Creates a sorted map entity view of a {@link DataStore}.
*
* @param store is the DataStore underlying the new collection.
*
* @param keyBinding is the binding used to translate between key buffers
* and key objects.
*
* @param valueEntityBinding is the binding used to translate between
* key/value buffers and entity value objects.
*
* @param writeAllowed is true to create a read-write collection or false
* to create a read-only collection.
*
* @throws IllegalArgumentException if formats are not consistently
* defined or a parameter is invalid.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public StoredSortedMap(DataStore store, DataBinding keyBinding,
EntityBinding valueEntityBinding,
boolean writeAllowed) {
super(new DataView(store, null, keyBinding, null,
valueEntityBinding, writeAllowed));
}
/**
* Creates a sorted map view of a {@link DataIndex}.
*
* @param index is the DataIndex underlying the new collection.
*
* @param keyBinding is the binding used to translate between key buffers
* and key objects.
*
* @param valueBinding is the binding used to translate between value
* buffers and value objects.
*
* @param writeAllowed is true to create a read-write collection or false
* to create a read-only collection.
*
* @throws IllegalArgumentException if formats are not consistently
* defined or a parameter is invalid.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public StoredSortedMap(DataIndex index, DataBinding keyBinding,
DataBinding valueBinding, boolean writeAllowed) {
super(new DataView(null, index, keyBinding, valueBinding,
null, writeAllowed));
}
/**
* Creates a sorted map entity view of a {@link DataIndex}.
*
* @param index is the DataIndex underlying the new collection.
*
* @param keyBinding is the binding used to translate between key buffers
* and key objects.
*
* @param valueEntityBinding is the binding used to translate between
* key/value buffers and entity value objects.
*
* @param writeAllowed is true to create a read-write collection or false
* to create a read-only collection.
*
* @throws IllegalArgumentException if formats are not consistently
* defined or a parameter is invalid.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public StoredSortedMap(DataIndex index, DataBinding keyBinding,
EntityBinding valueEntityBinding,
boolean writeAllowed) {
super(new DataView(null, index, keyBinding, null,
valueEntityBinding, writeAllowed));
}
StoredSortedMap(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 SortedMap#comparator}
* interface.
*
* @return null.
*/
public Comparator comparator() {
return null;
}
/**
* Returns the first (lowest) key currently in this sorted map.
* This method conforms to the {@link SortedMap#firstKey} interface.
*
* @return the first key.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public Object firstKey() {
return getFirstOrLastKey(true);
}
/**
* Returns the last (highest) element currently in this sorted map.
* This method conforms to the {@link SortedMap#lastKey} interface.
*
* @return the last key.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public Object lastKey() {
return getFirstOrLastKey(false);
}
private Object getFirstOrLastKey(boolean doGetFirst) {
DataCursor cursor = null;
try {
cursor = new DataCursor(view, false);
int err = cursor.get(null, null,
doGetFirst ? Db.DB_FIRST : Db.DB_LAST,
false);
return (err == 0) ? cursor.getCurrentKey() : null;
} catch (Exception e) {
throw StoredContainer.convertException(e);
} finally {
closeCursor(cursor);
}
}
/**
* Returns a view of the portion of this sorted set whose keys are
* strictly less than toKey.
* This method conforms to the {@link SortedMap#headMap} interface.
*
* @param toKey is the upper bound.
*
* @return the submap.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public SortedMap headMap(Object toKey) {
return subMap(null, false, toKey, false);
}
/**
* Returns a view of the portion of this sorted map whose elements are
* strictly less than toKey, optionally including toKey.
* This method does not exist in the standard {@link SortedMap} interface.
*
* @param toKey is the upper bound.
*
* @param toInclusive is true to include toKey.
*
* @return the submap.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public SortedMap headMap(Object toKey, boolean toInclusive) {
return subMap(null, false, toKey, toInclusive);
}
/**
* Returns a view of the portion of this sorted map whose elements are
* greater than or equal to fromKey.
* This method conforms to the {@link SortedMap#tailMap} interface.
*
* @param fromKey is the lower bound.
*
* @return the submap.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public SortedMap tailMap(Object fromKey) {
return subMap(fromKey, true, null, false);
}
/**
* Returns a view of the portion of this sorted map whose elements are
* strictly greater than fromKey, optionally including fromKey.
* This method does not exist in the standard {@link SortedMap} interface.
*
* @param fromKey is the lower bound.
*
* @param fromInclusive is true to include fromKey.
*
* @return the submap.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public SortedMap tailMap(Object fromKey, boolean fromInclusive) {
return subMap(fromKey, fromInclusive, null, false);
}
/**
* Returns a view of the portion of this sorted map whose elements range
* from fromKey, inclusive, to toKey, exclusive.
* This method conforms to the {@link SortedMap#subMap} interface.
*
* @param fromKey is the lower bound.
*
* @param toKey is the upper bound.
*
* @return the submap.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public SortedMap subMap(Object fromKey, Object toKey) {
return subMap(fromKey, true, toKey, false);
}
/**
* Returns a view of the portion of this sorted map whose elements are
* strictly greater than fromKey and strictly less than toKey,
* optionally including fromKey and toKey.
* This method does not exist in the standard {@link SortedMap} interface.
*
* @param fromKey is the lower bound.
*
* @param fromInclusive is true to include fromKey.
*
* @param toKey is the upper bound.
*
* @param toInclusive is true to include toKey.
*
* @return the submap.
*
* @throws RuntimeExceptionWrapper if a {@link DbException} is thrown.
*/
public SortedMap subMap(Object fromKey, boolean fromInclusive,
Object toKey, boolean toInclusive) {
try {
return new StoredSortedMap(
view.subView(fromKey, fromInclusive, toKey, toInclusive, null));
} catch (Exception e) {
throw StoredContainer.convertException(e);
}
}
}