org.apache.commons.collections.map.PredicatedSortedMap Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* 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
*
* 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.apache.commons.collections.map;
import java.util.Comparator;
import java.util.SortedMap;
import org.apache.commons.collections.Predicate;
/**
* Decorates another SortedMap to validate that additions
* match a specified predicate.
*
* This map exists to provide validation for the decorated map.
* It is normally created to decorate an empty map.
* If an object cannot be added to the map, an IllegalArgumentException is thrown.
*
* One usage would be to ensure that no null keys are added to the map.
*
SortedMap map = PredicatedSortedSet.decorate(new TreeMap(), NotNullPredicate.INSTANCE, null);
*
* Note that PredicatedSortedMap is not synchronized and is not thread-safe.
* If you wish to use this map from multiple threads concurrently, you must use
* appropriate synchronization. The simplest approach is to wrap this map
* using {@link java.util.Collections#synchronizedSortedMap}. This class may throw
* exceptions when accessed by concurrent threads without synchronization.
*
* This class is Serializable from Commons Collections 3.1.
*
* @since Commons Collections 3.0
* @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $
*
* @author Stephen Colebourne
* @author Paul Jack
*/
public class PredicatedSortedMap
extends PredicatedMap
implements SortedMap {
/** Serialization version */
private static final long serialVersionUID = 3359846175935304332L;
/**
* Factory method to create a predicated (validating) sorted map.
*
* If there are any elements already in the list being decorated, they
* are validated.
*
* @param map the map to decorate, must not be null
* @param keyPredicate the predicate to validate the keys, null means no check
* @param valuePredicate the predicate to validate to values, null means no check
* @throws IllegalArgumentException if the map is null
*/
public static SortedMap decorate(SortedMap map, Predicate keyPredicate, Predicate valuePredicate) {
return new PredicatedSortedMap(map, keyPredicate, valuePredicate);
}
//-----------------------------------------------------------------------
/**
* Constructor that wraps (not copies).
*
* @param map the map to decorate, must not be null
* @param keyPredicate the predicate to validate the keys, null means no check
* @param valuePredicate the predicate to validate to values, null means no check
* @throws IllegalArgumentException if the map is null
*/
protected PredicatedSortedMap(SortedMap map, Predicate keyPredicate, Predicate valuePredicate) {
super(map, keyPredicate, valuePredicate);
}
//-----------------------------------------------------------------------
/**
* Gets the map being decorated.
*
* @return the decorated map
*/
protected SortedMap getSortedMap() {
return (SortedMap) map;
}
//-----------------------------------------------------------------------
public Object firstKey() {
return getSortedMap().firstKey();
}
public Object lastKey() {
return getSortedMap().lastKey();
}
public Comparator comparator() {
return getSortedMap().comparator();
}
public SortedMap subMap(Object fromKey, Object toKey) {
SortedMap map = getSortedMap().subMap(fromKey, toKey);
return new PredicatedSortedMap(map, keyPredicate, valuePredicate);
}
public SortedMap headMap(Object toKey) {
SortedMap map = getSortedMap().headMap(toKey);
return new PredicatedSortedMap(map, keyPredicate, valuePredicate);
}
public SortedMap tailMap(Object fromKey) {
SortedMap map = getSortedMap().tailMap(fromKey);
return new PredicatedSortedMap(map, keyPredicate, valuePredicate);
}
}