    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.collections4.set;
    018
    019import java.util.Iterator;
    020import java.util.NavigableSet;
    021
    022import org.apache.commons.collections4.Predicate;
    023
    024/**
    025 * Decorates another <code>NavigableSet</code> to validate that all additions
    026 * match a specified predicate.
    027 * <p>
    028 * This set exists to provide validation for the decorated set.
    029 * It is normally created to decorate an empty set.
    030 * If an object cannot be added to the set, an IllegalArgumentException is thrown.
    031 * <p>
    032 * One usage would be to ensure that no null entries are added to the set.
    033 * <pre>
    034 * NavigableSet set =
    035 *   PredicatedSortedSet.predicatedNavigableSet(new TreeSet(),
    036 *                                              NotNullPredicate.notNullPredicate());
    037 * </pre>
    038 *
    039 * @param <E> the type of the elements in this set
    040 * @since 4.1
    041 */
    042public class PredicatedNavigableSet<E> extends PredicatedSortedSet<E> implements NavigableSet<E> {
    043
    044    /** Serialization version */
    045    private static final long serialVersionUID = 20150528L;
    046
    047    /**
    048     * Factory method to create a predicated (validating) navigable set.
    049     * <p>
    050     * If there are any elements already in the set being decorated, they
    051     * are validated.
    052     *
    053     * @param <E> the element type
    054     * @param set  the set to decorate, must not be null
    055     * @param predicate  the predicate to use for validation, must not be null
    056     * @return a new predicated navigable set.
    057     * @throws NullPointerException if set or predicate is null
    058     * @throws IllegalArgumentException if the set contains invalid elements
    059     * @since 4.0
    060     */
    061    public static <E> PredicatedNavigableSet<E> predicatedNavigableSet(final NavigableSet<E> set,
    062                                                                       final Predicate<? super E> predicate) {
    063        return new PredicatedNavigableSet<>(set, predicate);
    064    }
    065
    066    //-----------------------------------------------------------------------
    067    /**
    068     * Constructor that wraps (not copies).
    069     * <p>
    070     * If there are any elements already in the set being decorated, they
    071     * are validated.
    072     *
    073     * @param set  the set to decorate, must not be null
    074     * @param predicate  the predicate to use for validation, must not be null
    075     * @throws NullPointerException if set or predicate is null
    076     * @throws IllegalArgumentException if the set contains invalid elements
    077     */
    078    protected PredicatedNavigableSet(final NavigableSet<E> set, final Predicate<? super E> predicate) {
    079        super(set, predicate);
    080    }
    081
    082    /**
    083     * Gets the navigable set being decorated.
    084     *
    085     * @return the decorated navigable set
    086     */
    087    @Override
    088    protected NavigableSet<E> decorated() {
    089        return (NavigableSet<E>) super.decorated();
    090    }
    091
    092    //-----------------------------------------------------------------------
    093
    094    @Override
    095    public E lower(final E e) {
    096        return decorated().lower(e);
    097    }
    098
    099    @Override
    100    public E floor(final E e) {
    101        return decorated().floor(e);
    102    }
    103
    104    @Override
    105    public E ceiling(final E e) {
    106        return decorated().ceiling(e);
    107    }
    108
    109    @Override
    110    public E higher(final E e) {
    111        return decorated().higher(e);
    112    }
    113
    114    @Override
    115    public E pollFirst() {
    116        return decorated().pollFirst();
    117    }
    118
    119    @Override
    120    public E pollLast() {
    121        return decorated().pollLast();
    122    }
    123
    124    @Override
    125    public NavigableSet<E> descendingSet() {
    126        return predicatedNavigableSet(decorated().descendingSet(), predicate);
    127    }
    128
    129    @Override
    130    public Iterator<E> descendingIterator() {
    131        return decorated().descendingIterator();
    132    }
    133
    134    @Override
    135    public NavigableSet<E> subSet(final E fromElement, final boolean fromInclusive, final E toElement,
    136            final boolean toInclusive) {
    137        final NavigableSet<E> sub = decorated().subSet(fromElement, fromInclusive, toElement, toInclusive);
    138        return predicatedNavigableSet(sub, predicate);
    139    }
    140
    141    @Override
    142    public NavigableSet<E> headSet(final E toElement, final boolean inclusive) {
    143        final NavigableSet<E> head = decorated().headSet(toElement, inclusive);
    144        return predicatedNavigableSet(head, predicate);
    145    }
    146
    147    @Override
    148    public NavigableSet<E> tailSet(final E fromElement, final boolean inclusive) {
    149        final NavigableSet<E> tail = decorated().tailSet(fromElement, inclusive);
    150        return predicatedNavigableSet(tail, predicate);
    151    }
    152
    153}