Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
FunctionPredicate |
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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.Predicate; | |
23 | ||
24 | /** | |
25 | * Adapts a <code>Boolean</code>-valued | |
26 | * {@link Function Function} to the | |
27 | * {@link Predicate Predicate} interface. | |
28 | * <p/> | |
29 | * Note that although this class implements | |
30 | * {@link Serializable}, a given instance will | |
31 | * only be truly <code>Serializable</code> if the | |
32 | * underlying functor is. Attempts to serialize | |
33 | * an instance whose delegate is not | |
34 | * <code>Serializable</code> will result in an exception. | |
35 | * | |
36 | * @version $Revision: 1157608 $ $Date: 2011-08-14 21:40:57 +0200 (Sun, 14 Aug 2011) $ | |
37 | * @author Rodney Waldhoff | |
38 | */ | |
39 | public final class FunctionPredicate implements Predicate, Serializable { | |
40 | ||
41 | /** | |
42 | * serialVersionUID declaration. | |
43 | */ | |
44 | private static final long serialVersionUID = 6564796937660102222L; | |
45 | /** The {@link Function Function} I'm wrapping. */ | |
46 | private final Function<Boolean> function; | |
47 | ||
48 | /** | |
49 | * Create a new FunctionPredicate. | |
50 | * @param function to adapt | |
51 | */ | |
52 | 20 | public FunctionPredicate(Function<Boolean> function) { |
53 | 20 | if (function == null) { |
54 | 0 | throw new IllegalArgumentException("Function argument was null"); |
55 | } | |
56 | 20 | this.function = function; |
57 | 20 | } |
58 | ||
59 | /** | |
60 | * Returns the <code>boolean</code> value of the non-<code>null</code> | |
61 | * <code>Boolean</code> returned by the {@link Function#evaluate evaluate} | |
62 | * method of my underlying function. | |
63 | * {@inheritDoc} | |
64 | */ | |
65 | public boolean test() { | |
66 | 4 | return function.evaluate(); |
67 | } | |
68 | ||
69 | /** | |
70 | * {@inheritDoc} | |
71 | */ | |
72 | public boolean equals(Object that) { | |
73 | 22 | return that == this || (that instanceof FunctionPredicate && equals((FunctionPredicate) that)); |
74 | } | |
75 | ||
76 | /** | |
77 | * Learn whether another FunctionPredicate is equal to this. | |
78 | * @param that FunctionPredicate to test | |
79 | * @return boolean | |
80 | */ | |
81 | public boolean equals(FunctionPredicate that) { | |
82 | 14 | return null != that && (null == function ? null == that.function : function.equals(that.function)); |
83 | } | |
84 | ||
85 | /** | |
86 | * {@inheritDoc} | |
87 | */ | |
88 | public int hashCode() { | |
89 | 24 | int hash = "FunctionPredicate".hashCode(); |
90 | 24 | if (null != function) { |
91 | 24 | hash ^= function.hashCode(); |
92 | } | |
93 | 24 | return hash; |
94 | } | |
95 | ||
96 | /** | |
97 | * {@inheritDoc} | |
98 | */ | |
99 | public String toString() { | |
100 | 16 | return "FunctionPredicate<" + function + ">"; |
101 | } | |
102 | ||
103 | /** | |
104 | * Adapt a Function as a Predicate. | |
105 | * @param function to adapt | |
106 | * @return FunctionPredicate | |
107 | */ | |
108 | public static FunctionPredicate adapt(Function<Boolean> function) { | |
109 | 6 | return null == function ? null : new FunctionPredicate(function); |
110 | } | |
111 | } |