| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| ConditionalUnaryFunction |
|
| 4.0;4 |
| 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.UnaryFunction; | |
| 22 | import org.apache.commons.functor.UnaryPredicate; | |
| 23 | ||
| 24 | /** | |
| 25 | * A {@link UnaryFunction UnaryFunction} | |
| 26 | * similiar to Java's "ternary" | |
| 27 | * or "conditional" operator (<code>? :</code>). | |
| 28 | * Given a {@link UnaryPredicate predicate} | |
| 29 | * <i>p</i> and {@link UnaryFunction functions} | |
| 30 | * <i>f</i> and <i>g</i>, {@link #evaluate evalautes} | |
| 31 | * to | |
| 32 | * <code>p.test(x) ? f.evaluate(x) : g.evaluate(x)</code>. | |
| 33 | * <p> | |
| 34 | * Note that although this class implements | |
| 35 | * {@link Serializable}, a given instance will | |
| 36 | * only be truly <code>Serializable</code> if all the | |
| 37 | * underlying functors are. Attempts to serialize | |
| 38 | * an instance whose delegates are not all | |
| 39 | * <code>Serializable</code> will result in an exception. | |
| 40 | * </p> | |
| 41 | * @version $Revision: 1170778 $ $Date: 2011-09-14 21:15:01 +0200 (Wed, 14 Sep 2011) $ | |
| 42 | * @author Rodney Waldhoff | |
| 43 | */ | |
| 44 | public final class ConditionalUnaryFunction<A, T> implements UnaryFunction<A, T>, Serializable { | |
| 45 | /** | |
| 46 | * serialVersionUID declaration. | |
| 47 | */ | |
| 48 | private static final long serialVersionUID = -8152490481969255068L; | |
| 49 | ||
| 50 | /** Base hash integer used to shift hash */ | |
| 51 | private static final int HASH_SHIFT = 4; | |
| 52 | // attributes | |
| 53 | // ------------------------------------------------------------------------ | |
| 54 | private final UnaryPredicate<? super A> ifPred; | |
| 55 | private final UnaryFunction<? super A, ? extends T> thenFunc; | |
| 56 | private final UnaryFunction<? super A, ? extends T> elseFunc; | |
| 57 | ||
| 58 | // constructor | |
| 59 | // ------------------------------------------------------------------------ | |
| 60 | /** | |
| 61 | * Create a new ConditionalUnaryFunction. | |
| 62 | * @param ifPred if | |
| 63 | * @param thenFunc then | |
| 64 | * @param elseFunc else | |
| 65 | */ | |
| 66 | public ConditionalUnaryFunction(UnaryPredicate<? super A> ifPred, UnaryFunction<? super A, ? extends T> thenFunc, | |
| 67 | 20 | UnaryFunction<? super A, ? extends T> elseFunc) { |
| 68 | 20 | if (ifPred == null) { |
| 69 | 0 | throw new IllegalArgumentException("UnaryPredicate argument was null"); |
| 70 | } | |
| 71 | 20 | this.ifPred = ifPred; |
| 72 | 20 | if (thenFunc == null || elseFunc == null) { |
| 73 | 0 | throw new IllegalArgumentException("One or more UnaryFunction arguments was null"); |
| 74 | } | |
| 75 | 20 | this.thenFunc = thenFunc; |
| 76 | 20 | this.elseFunc = elseFunc; |
| 77 | 20 | } |
| 78 | ||
| 79 | // predicate interface | |
| 80 | // ------------------------------------------------------------------------ | |
| 81 | /** | |
| 82 | * {@inheritDoc} | |
| 83 | */ | |
| 84 | public T evaluate(A obj) { | |
| 85 | 4 | if (ifPred.test(obj)) { |
| 86 | 2 | return thenFunc.evaluate(obj); |
| 87 | } else { | |
| 88 | 2 | return elseFunc.evaluate(obj); |
| 89 | } | |
| 90 | } | |
| 91 | ||
| 92 | /** | |
| 93 | * {@inheritDoc} | |
| 94 | */ | |
| 95 | public boolean equals(Object that) { | |
| 96 | 24 | return that == this || (that instanceof ConditionalUnaryFunction<?, ?> |
| 97 | && equals((ConditionalUnaryFunction<?, ?>) that)); | |
| 98 | } | |
| 99 | ||
| 100 | /** | |
| 101 | * Learn whether another ConditionalUnaryFunction is equal to this. | |
| 102 | * @param that ConditionalUnaryFunction to test | |
| 103 | * @return boolean | |
| 104 | */ | |
| 105 | public boolean equals(ConditionalUnaryFunction<?, ?> that) { | |
| 106 | 18 | return null != that |
| 107 | && (null == ifPred ? null == that.ifPred : ifPred.equals(that.ifPred)) | |
| 108 | && (null == thenFunc ? null == that.thenFunc : thenFunc.equals(that.thenFunc)) | |
| 109 | && (null == elseFunc ? null == that.elseFunc : elseFunc.equals(that.elseFunc)); | |
| 110 | } | |
| 111 | ||
| 112 | /** | |
| 113 | * {@inheritDoc} | |
| 114 | */ | |
| 115 | public int hashCode() { | |
| 116 | 26 | int hash = "ConditionalUnaryFunction".hashCode(); |
| 117 | 26 | if (null != ifPred) { |
| 118 | 26 | hash <<= HASH_SHIFT; |
| 119 | 26 | hash ^= ifPred.hashCode(); |
| 120 | } | |
| 121 | 26 | if (null != thenFunc) { |
| 122 | 26 | hash <<= HASH_SHIFT; |
| 123 | 26 | hash ^= thenFunc.hashCode(); |
| 124 | } | |
| 125 | 26 | if (null != elseFunc) { |
| 126 | 26 | hash <<= HASH_SHIFT; |
| 127 | 26 | hash ^= elseFunc.hashCode(); |
| 128 | } | |
| 129 | 26 | return hash; |
| 130 | } | |
| 131 | ||
| 132 | /** | |
| 133 | * {@inheritDoc} | |
| 134 | */ | |
| 135 | public String toString() { | |
| 136 | 18 | return "ConditionalUnaryFunction<" + ifPred + "?" + thenFunc + ":" + elseFunc + ">"; |
| 137 | } | |
| 138 | ||
| 139 | } |