| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| TransposedPredicate |
|
| 2.142857142857143;2.143 |
| 1 | /* | |
| 2 | * Licensed to the Apache Software Foundation (ASF) under one or more | |
| 3 | * contributor license agreements. See the NOTICE file distributed with | |
| 4 | * this work for additional information regarding copyright ownership. | |
| 5 | * The ASF licenses this file to You under the Apache License, Version 2.0 | |
| 6 | * (the "License"); you may not use this file except in compliance with | |
| 7 | * the License. You may obtain a copy of the License at | |
| 8 | * | |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 | |
| 10 | * | |
| 11 | * Unless required by applicable law or agreed to in writing, software | |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, | |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
| 14 | * See the License for the specific language governing permissions and | |
| 15 | * limitations under the License. | |
| 16 | */ | |
| 17 | package org.apache.commons.functor.core.composite; | |
| 18 | ||
| 19 | import java.io.Serializable; | |
| 20 | ||
| 21 | import org.apache.commons.functor.BinaryPredicate; | |
| 22 | ||
| 23 | /** | |
| 24 | * Transposes (swaps) the arguments to some other | |
| 25 | * {@link BinaryPredicate predicate}. | |
| 26 | * For example, given a predicate <i>p</i> | |
| 27 | * and the ordered pair of arguments <i>a</i>, | |
| 28 | * <i>b</i>. | |
| 29 | * {@link #test tests} | |
| 30 | * <code>p.test(b,a)</code>. | |
| 31 | * <p> | |
| 32 | * Note that although this class implements | |
| 33 | * {@link Serializable}, a given instance will | |
| 34 | * only be truly <code>Serializable</code> if the | |
| 35 | * underlying functor is. Attempts to serialize | |
| 36 | * an instance whose delegate is not | |
| 37 | * <code>Serializable</code> will result in an exception. | |
| 38 | * </p> | |
| 39 | * @version $Revision: 1170828 $ $Date: 2011-09-14 22:00:19 +0200 (Wed, 14 Sep 2011) $ | |
| 40 | * @author Rodney Waldhoff | |
| 41 | */ | |
| 42 | public class TransposedPredicate<L, R> implements BinaryPredicate<L, R>, Serializable { | |
| 43 | /** | |
| 44 | * serialVersionUID declaration. | |
| 45 | */ | |
| 46 | private static final long serialVersionUID = 3441209087576289240L; | |
| 47 | // attributes | |
| 48 | // ------------------------------------------------------------------------ | |
| 49 | private final BinaryPredicate<? super R, ? super L> predicate; | |
| 50 | ||
| 51 | // constructor | |
| 52 | // ------------------------------------------------------------------------ | |
| 53 | /** | |
| 54 | * Create a new TransposedPredicate. | |
| 55 | * @param predicate the BinaryPredicate to transpose | |
| 56 | */ | |
| 57 | 20 | public TransposedPredicate(BinaryPredicate<? super R, ? super L> predicate) { |
| 58 | 20 | if (predicate == null) { |
| 59 | 0 | throw new IllegalArgumentException("BinaryPredicate argument must not be null"); |
| 60 | } | |
| 61 | 20 | this.predicate = predicate; |
| 62 | 20 | } |
| 63 | ||
| 64 | // functor interface | |
| 65 | // ------------------------------------------------------------------------ | |
| 66 | /** | |
| 67 | * {@inheritDoc} | |
| 68 | */ | |
| 69 | public final boolean test(L left, R right) { | |
| 70 | 4 | return predicate.test(right, left); |
| 71 | } | |
| 72 | ||
| 73 | /** | |
| 74 | * {@inheritDoc} | |
| 75 | */ | |
| 76 | public boolean equals(Object that) { | |
| 77 | 26 | return that == this || (that instanceof TransposedPredicate<?, ?> && equals((TransposedPredicate<?, ?>) that)); |
| 78 | } | |
| 79 | ||
| 80 | /** | |
| 81 | * Learn whether another TransposedPredicate is equal to this. | |
| 82 | * @param that the TransposedPredicate to test | |
| 83 | * @return boolean | |
| 84 | */ | |
| 85 | public boolean equals(TransposedPredicate<?, ?> that) { | |
| 86 | 18 | return null != that && (null == predicate ? null == that.predicate : predicate.equals(that.predicate)); |
| 87 | } | |
| 88 | ||
| 89 | /** | |
| 90 | * {@inheritDoc} | |
| 91 | */ | |
| 92 | public int hashCode() { | |
| 93 | 28 | int hash = "TransposedPredicate".hashCode(); |
| 94 | 28 | if (null != predicate) { |
| 95 | 28 | hash ^= predicate.hashCode(); |
| 96 | } | |
| 97 | 28 | return hash; |
| 98 | } | |
| 99 | ||
| 100 | /** | |
| 101 | * {@inheritDoc} | |
| 102 | */ | |
| 103 | public String toString() { | |
| 104 | 20 | return "TransposedPredicate<" + predicate + ">"; |
| 105 | } | |
| 106 | ||
| 107 | // static | |
| 108 | // ------------------------------------------------------------------------ | |
| 109 | /** | |
| 110 | * Return the transposition of <code>p</code>. | |
| 111 | * @param p BinaryPredicate to transpose | |
| 112 | * @return TransposedPredicate | |
| 113 | */ | |
| 114 | public static <L, R> TransposedPredicate<R, L> transpose(BinaryPredicate<? super L, ? super R> p) { | |
| 115 | 6 | return null == p ? null : new TransposedPredicate<R, L>(p); |
| 116 | } | |
| 117 | ||
| 118 | } |