    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 * <p>
    033 * One usage would be to ensure that no null entries are added to the set.
    034 * </p>
    035 * <pre>
    036 * NavigableSet set =
    037 *   PredicatedSortedSet.predicatedNavigableSet(new TreeSet(),
    038 *                                              NotNullPredicate.notNullPredicate());
    039 * </pre>
    040 *
    041 * @param <E> the type of the elements in this set
    042 * @since 4.1
    043 */
    044public class PredicatedNavigableSet<E> extends PredicatedSortedSet<E> implements NavigableSet<E> {
    045
    046    /** Serialization version */
    047    private static final long serialVersionUID = 20150528L;
    048
    049    /**
    050     * Factory method to create a predicated (validating) navigable set.
    051     * <p>
    052     * If there are any elements already in the set being decorated, they
    053     * are validated.
    054     *
    055     * @param <E> the element type
    056     * @param set  the set to decorate, must not be null
    057     * @param predicate  the predicate to use for validation, must not be null
    058     * @return a new predicated navigable set.
    059     * @throws NullPointerException if set or predicate is null
    060     * @throws IllegalArgumentException if the set contains invalid elements
    061     * @since 4.0
    062     */
    063    public static <E> PredicatedNavigableSet<E> predicatedNavigableSet(final NavigableSet<E> set,
    064                                                                       final Predicate<? super E> predicate) {
    065        return new PredicatedNavigableSet<>(set, predicate);
    066    }
    067
    068    //-----------------------------------------------------------------------
    069    /**
    070     * Constructor that wraps (not copies).
    071     * <p>
    072     * If there are any elements already in the set being decorated, they
    073     * are validated.
    074     *
    075     * @param set  the set to decorate, must not be null
    076     * @param predicate  the predicate to use for validation, must not be null
    077     * @throws NullPointerException if set or predicate is null
    078     * @throws IllegalArgumentException if the set contains invalid elements
    079     */
    080    protected PredicatedNavigableSet(final NavigableSet<E> set, final Predicate<? super E> predicate) {
    081        super(set, predicate);
    082    }
    083
    084    /**
    085     * Gets the navigable set being decorated.
    086     *
    087     * @return the decorated navigable set
    088     */
    089    @Override
    090    protected NavigableSet<E> decorated() {
    091        return (NavigableSet<E>) super.decorated();
    092    }
    093
    094    //-----------------------------------------------------------------------
    095
    096    @Override
    097    public E lower(final E e) {
    098        return decorated().lower(e);
    099    }
    100
    101    @Override
    102    public E floor(final E e) {
    103        return decorated().floor(e);
    104    }
    105
    106    @Override
    107    public E ceiling(final E e) {
    108        return decorated().ceiling(e);
    109    }
    110
    111    @Override
    112    public E higher(final E e) {
    113        return decorated().higher(e);
    114    }
    115
    116    @Override
    117    public E pollFirst() {
    118        return decorated().pollFirst();
    119    }
    120
    121    @Override
    122    public E pollLast() {
    123        return decorated().pollLast();
    124    }
    125
    126    @Override
    127    public NavigableSet<E> descendingSet() {
    128        return predicatedNavigableSet(decorated().descendingSet(), predicate);
    129    }
    130
    131    @Override
    132    public Iterator<E> descendingIterator() {
    133        return decorated().descendingIterator();
    134    }
    135
    136    @Override
    137    public NavigableSet<E> subSet(final E fromElement, final boolean fromInclusive, final E toElement,
    138            final boolean toInclusive) {
    139        final NavigableSet<E> sub = decorated().subSet(fromElement, fromInclusive, toElement, toInclusive);
    140        return predicatedNavigableSet(sub, predicate);
    141    }
    142
    143    @Override
    144    public NavigableSet<E> headSet(final E toElement, final boolean inclusive) {
    145        final NavigableSet<E> head = decorated().headSet(toElement, inclusive);
    146        return predicatedNavigableSet(head, predicate);
    147    }
    148
    149    @Override
    150    public NavigableSet<E> tailSet(final E fromElement, final boolean inclusive) {
    151        final NavigableSet<E> tail = decorated().tailSet(fromElement, inclusive);
    152        return predicatedNavigableSet(tail, predicate);
    153    }
    154
    155}