| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| Identity |
|
| 1.0;1 |
| 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; | |
| 18 | ||
| 19 | import java.io.Serializable; | |
| 20 | ||
| 21 | import org.apache.commons.functor.UnaryFunction; | |
| 22 | import org.apache.commons.functor.UnaryPredicate; | |
| 23 | ||
| 24 | /** | |
| 25 | * {@link #evaluate Evaluates} to its input argument. | |
| 26 | * | |
| 27 | * {@link #test Tests} to the <code>boolean</code> | |
| 28 | * value of the <code>Boolean</code>-valued parameter. | |
| 29 | * The {@link #test} method throws an exception if | |
| 30 | * the parameter isn't a non-<code>null</code> | |
| 31 | * <code>Boolean</code>. | |
| 32 | * | |
| 33 | * @param <T> the returned value type. | |
| 34 | * @version $Revision: 1160385 $ $Date: 2011-08-22 21:28:37 +0200 (Mon, 22 Aug 2011) $ | |
| 35 | * @author Rodney Waldhoff | |
| 36 | */ | |
| 37 | public final class Identity<T> implements UnaryFunction<T, T>, UnaryPredicate<T>, Serializable { | |
| 38 | // static attributes | |
| 39 | // ------------------------------------------------------------------------ | |
| 40 | /** | |
| 41 | * A generic {@code Identity<Object>} instance. | |
| 42 | */ | |
| 43 | 2 | public static final Identity<Object> INSTANCE = new Identity<Object>(); |
| 44 | ||
| 45 | /** | |
| 46 | * serialVersionUID declaration. | |
| 47 | */ | |
| 48 | private static final long serialVersionUID = 4145504259013789494L; | |
| 49 | ||
| 50 | // constructor | |
| 51 | // ------------------------------------------------------------------------ | |
| 52 | ||
| 53 | /** | |
| 54 | * Create a new Identity. | |
| 55 | */ | |
| 56 | 154 | public Identity() { |
| 57 | 154 | } |
| 58 | ||
| 59 | // function interface | |
| 60 | // ------------------------------------------------------------------------ | |
| 61 | ||
| 62 | /** | |
| 63 | * {@inheritDoc} | |
| 64 | */ | |
| 65 | public T evaluate(T obj) { | |
| 66 | 340 | return obj; |
| 67 | } | |
| 68 | ||
| 69 | /** | |
| 70 | * {@inheritDoc} | |
| 71 | */ | |
| 72 | public boolean test(Object obj) { | |
| 73 | 22 | return test((Boolean) obj); |
| 74 | } | |
| 75 | ||
| 76 | /** | |
| 77 | * Test a Boolean object by returning its <code>booleanValue</code>. | |
| 78 | * @param bool Boolean | |
| 79 | * @return boolean | |
| 80 | */ | |
| 81 | public boolean test(Boolean bool) { | |
| 82 | 20 | return bool.booleanValue(); |
| 83 | } | |
| 84 | ||
| 85 | /** | |
| 86 | * {@inheritDoc} | |
| 87 | */ | |
| 88 | public boolean equals(Object that) { | |
| 89 | 138 | return (that instanceof Identity<?>); |
| 90 | } | |
| 91 | ||
| 92 | /** | |
| 93 | * {@inheritDoc} | |
| 94 | */ | |
| 95 | public int hashCode() { | |
| 96 | 436 | return "Identity".hashCode(); |
| 97 | } | |
| 98 | ||
| 99 | /** | |
| 100 | * {@inheritDoc} | |
| 101 | */ | |
| 102 | public String toString() { | |
| 103 | 324 | return "Identity"; |
| 104 | } | |
| 105 | ||
| 106 | // static methods | |
| 107 | // ------------------------------------------------------------------------ | |
| 108 | ||
| 109 | /** | |
| 110 | * Get an Identity instance. | |
| 111 | * @param <T> the identity returned value type. | |
| 112 | * @return Identity | |
| 113 | */ | |
| 114 | public static <T> Identity<T> instance() { | |
| 115 | 66 | return new Identity<T>(); |
| 116 | } | |
| 117 | ||
| 118 | } |