| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| BoundPredicate |
|
| 2.5714285714285716;2.571 |
| 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.adapter; | |
| 18 | ||
| 19 | import java.io.Serializable; | |
| 20 | ||
| 21 | import org.apache.commons.functor.Predicate; | |
| 22 | import org.apache.commons.functor.UnaryPredicate; | |
| 23 | ||
| 24 | /** | |
| 25 | * Adapts a | |
| 26 | * {@link UnaryPredicate UnaryPredicate} | |
| 27 | * to the | |
| 28 | * {@link Predicate Predicate} interface | |
| 29 | * using a constant unary argument. | |
| 30 | * <p/> | |
| 31 | * Note that although this class implements | |
| 32 | * {@link Serializable}, a given instance will | |
| 33 | * only be truly <code>Serializable</code> if the | |
| 34 | * underlying objects are. Attempts to serialize | |
| 35 | * an instance whose delegates are not | |
| 36 | * <code>Serializable</code> will result in an exception. | |
| 37 | * | |
| 38 | * @version $Revision: 1156320 $ $Date: 2011-08-10 21:14:50 +0200 (Wed, 10 Aug 2011) $ | |
| 39 | * @author Rodney Waldhoff | |
| 40 | */ | |
| 41 | public final class BoundPredicate implements Predicate, Serializable { | |
| 42 | /** | |
| 43 | * serialVersionUID declaration. | |
| 44 | */ | |
| 45 | private static final long serialVersionUID = -5721164265625291834L; | |
| 46 | /** The {@link UnaryPredicate UnaryPredicate} I'm wrapping. */ | |
| 47 | private final UnaryPredicate<Object> predicate; | |
| 48 | /** The parameter to pass to {@code predicate}. */ | |
| 49 | private final Object param; | |
| 50 | ||
| 51 | /** | |
| 52 | * Create a new BoundPredicate instance. | |
| 53 | * @param <A> input type | |
| 54 | * @param predicate the predicate to adapt | |
| 55 | * @param arg the constant argument to use | |
| 56 | */ | |
| 57 | @SuppressWarnings("unchecked") | |
| 58 | 30 | public <A> BoundPredicate(UnaryPredicate<? super A> predicate, A arg) { |
| 59 | 30 | if (predicate == null) { |
| 60 | 0 | throw new IllegalArgumentException("UnaryPredicate argument was null"); |
| 61 | } | |
| 62 | 30 | this.predicate = (UnaryPredicate<Object>) predicate; |
| 63 | 30 | this.param = arg; |
| 64 | 30 | } |
| 65 | ||
| 66 | /** | |
| 67 | * {@inheritDoc} | |
| 68 | */ | |
| 69 | public boolean test() { | |
| 70 | 30 | return predicate.test(param); |
| 71 | } | |
| 72 | ||
| 73 | /** | |
| 74 | * {@inheritDoc} | |
| 75 | */ | |
| 76 | public boolean equals(Object that) { | |
| 77 | 30 | return that == this || (that instanceof BoundPredicate && equals((BoundPredicate) that)); |
| 78 | } | |
| 79 | ||
| 80 | /** | |
| 81 | * Learn whether another BoundPredicate is equal to this. | |
| 82 | * @param that BoundPredicate to test | |
| 83 | * @return boolean | |
| 84 | */ | |
| 85 | public boolean equals(BoundPredicate that) { | |
| 86 | 22 | return null != that |
| 87 | && (null == predicate ? null == that.predicate : predicate.equals(that.predicate)) | |
| 88 | && (null == param ? null == that.param : param.equals(that.param)); | |
| 89 | ||
| 90 | } | |
| 91 | ||
| 92 | /** | |
| 93 | * {@inheritDoc} | |
| 94 | */ | |
| 95 | public int hashCode() { | |
| 96 | 32 | int hash = "BoundPredicate".hashCode(); |
| 97 | 32 | if (null != predicate) { |
| 98 | 32 | hash <<= 2; |
| 99 | 32 | hash ^= predicate.hashCode(); |
| 100 | } | |
| 101 | 32 | if (null != param) { |
| 102 | 30 | hash <<= 2; |
| 103 | 30 | hash ^= param.hashCode(); |
| 104 | } | |
| 105 | 32 | return hash; |
| 106 | } | |
| 107 | ||
| 108 | /** | |
| 109 | * {@inheritDoc} | |
| 110 | */ | |
| 111 | public String toString() { | |
| 112 | 24 | return "BoundPredicate<" + predicate + "(" + param + ")>"; |
| 113 | } | |
| 114 | ||
| 115 | /** | |
| 116 | * Adapt the given, possibly-<code>null</code>, | |
| 117 | * {@link UnaryPredicate UnaryPredicate} to the | |
| 118 | * {@link Predicate Predicate} interface by binding | |
| 119 | * the specified <code>Object</code> as a constant | |
| 120 | * argument. | |
| 121 | * When the given <code>UnaryPredicate</code> is <code>null</code>, | |
| 122 | * returns <code>null</code>. | |
| 123 | * | |
| 124 | * @param <A> input type | |
| 125 | * @param predicate the possibly-<code>null</code> | |
| 126 | * {@link UnaryPredicate UnaryPredicate} to adapt | |
| 127 | * @param arg the object to bind as a constant argument | |
| 128 | * @return a <code>BoundPredicate</code> wrapping the given | |
| 129 | * {@link UnaryPredicate UnaryPredicate}, or <code>null</code> | |
| 130 | * if the given <code>UnaryPredicate</code> is <code>null</code> | |
| 131 | */ | |
| 132 | public static <A> BoundPredicate bind(UnaryPredicate<? super A> predicate, A arg) { | |
| 133 | 6 | return null == predicate ? null : new BoundPredicate(predicate, arg); |
| 134 | } | |
| 135 | ||
| 136 | } |