Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
FunctionUnaryFunction |
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| 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.adapter; | |
18 | ||
19 | import java.io.Serializable; | |
20 | ||
21 | import org.apache.commons.functor.Function; | |
22 | import org.apache.commons.functor.UnaryFunction; | |
23 | ||
24 | /** | |
25 | * Adapts a | |
26 | * {@link Function Function} | |
27 | * to the | |
28 | * {@link UnaryFunction UnaryFunction} interface | |
29 | * by ignoring the 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 functor is. Attempts to serialize | |
35 | * an instance whose delegate is not | |
36 | * <code>Serializable</code> will result in an exception. | |
37 | * | |
38 | * @param <A> the argument type. | |
39 | * @param <T> the returned value type. | |
40 | * @version $Revision: 1157609 $ $Date: 2011-08-14 21:42:21 +0200 (Sun, 14 Aug 2011) $ | |
41 | * @author Rodney Waldhoff | |
42 | */ | |
43 | public final class FunctionUnaryFunction<A, T> implements UnaryFunction<A, T>, Serializable { | |
44 | /** | |
45 | * serialVersionUID declaration. | |
46 | */ | |
47 | private static final long serialVersionUID = 1993899041200996524L; | |
48 | /** The {@link Function Function} I'm wrapping. */ | |
49 | private final Function<? extends T> function; | |
50 | ||
51 | /** | |
52 | * Create a new FunctionUnaryFunction. | |
53 | * @param function to adapt | |
54 | */ | |
55 | 18 | public FunctionUnaryFunction(Function<? extends T> function) { |
56 | 18 | if (function == null) { |
57 | 0 | throw new IllegalArgumentException("Function argument was null"); |
58 | } | |
59 | 18 | this.function = function; |
60 | 18 | } |
61 | ||
62 | /** | |
63 | * {@inheritDoc} | |
64 | */ | |
65 | public T evaluate(A obj) { | |
66 | 4 | return function.evaluate(); |
67 | } | |
68 | ||
69 | /** | |
70 | * {@inheritDoc} | |
71 | */ | |
72 | public boolean equals(Object that) { | |
73 | 24 | return that == this || (that instanceof FunctionUnaryFunction<?, ?> |
74 | && equals((FunctionUnaryFunction<?, ?>) that)); | |
75 | } | |
76 | ||
77 | /** | |
78 | * Learn whether another FunctionUnaryFunction is equal to this. | |
79 | * @param that FunctionUnaryFunction to test | |
80 | * @return boolean | |
81 | */ | |
82 | public boolean equals(FunctionUnaryFunction<?, ?> that) { | |
83 | 14 | return null != that && (null == function ? null == that.function : function.equals(that.function)); |
84 | } | |
85 | ||
86 | /** | |
87 | * {@inheritDoc} | |
88 | */ | |
89 | public int hashCode() { | |
90 | 26 | int hash = "FunctionUnaryFunction".hashCode(); |
91 | 26 | if (null != function) { |
92 | 26 | hash ^= function.hashCode(); |
93 | } | |
94 | 26 | return hash; |
95 | } | |
96 | ||
97 | /** | |
98 | * {@inheritDoc} | |
99 | */ | |
100 | public String toString() { | |
101 | 18 | return "FunctionUnaryFunction<" + function + ">"; |
102 | } | |
103 | ||
104 | /** | |
105 | * Adapt a Function to the UnaryFunction interface. | |
106 | * @param <A> arg type | |
107 | * @param <T> result type | |
108 | * @param function to adapt | |
109 | * @return FunctionUnaryFunction | |
110 | */ | |
111 | public static <A, T> FunctionUnaryFunction<A, T> adapt(Function<? extends T> function) { | |
112 | 4 | return null == function ? null : new FunctionUnaryFunction<A, T>(function); |
113 | } | |
114 | ||
115 | } |