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 import java.util.ArrayList;
21 import java.util.List;
22
23 import org.apache.commons.functor.BinaryPredicate;
24
25 /**
26 * Abstract base class for {@link BinaryPredicate BinaryPredicates}
27 * composed of a list of {@link BinaryPredicate BinaryPredicates}.
28 * <p>
29 * Note that although this class implements
30 * {@link Serializable}, a given instance will
31 * only be truly <code>Serializable</code> if all the
32 * underlying functors are. Attempts to serialize
33 * an instance whose delegates are not all
34 * <code>Serializable</code> will result in an exception.
35 * </p>
36 * @version $Revision: 1156337 $ $Date: 2011-08-10 21:44:54 +0200 (Wed, 10 Aug 2011) $
37 * @author Rodney Waldhoff
38 */
39 abstract class BaseBinaryPredicateList<L, R> implements BinaryPredicate<L, R>, Serializable {
40
41 /**
42 * serialVersionUID declaration.
43 */
44 private static final long serialVersionUID = -8218822378485819939L;
45 // attributes
46 // ------------------------------------------------------------------------
47 private final List<BinaryPredicate<? super L, ? super R>> list =
48 new ArrayList<BinaryPredicate<? super L, ? super R>>();
49
50 // constructor
51 // ------------------------------------------------------------------------
52 /**
53 * Create a new BaseBinaryPredicateList.
54 */
55 protected BaseBinaryPredicateList() {
56 super();
57 }
58
59 /**
60 * Create a new BaseBinaryPredicateList instance.
61 *
62 * @param predicates to add
63 */
64 protected BaseBinaryPredicateList(BinaryPredicate<? super L, ? super R>... predicates) {
65 this();
66 if (predicates != null) {
67 for (BinaryPredicate<? super L, ? super R> p : predicates) {
68 addBinaryPredicate(p);
69 }
70 }
71 }
72
73 /**
74 * Create a new BaseBinaryPredicateList instance.
75 *
76 * @param predicates to add
77 */
78 protected BaseBinaryPredicateList(Iterable<BinaryPredicate<? super L, ? super R>> predicates) {
79 this();
80 if (predicates != null) {
81 for (BinaryPredicate<? super L, ? super R> p : predicates) {
82 addBinaryPredicate(p);
83 }
84 }
85 }
86
87 // abstract
88 // ------------------------------------------------------------------------
89 /**
90 * {@inheritDoc}
91 */
92 public abstract boolean equals(Object that);
93
94 /**
95 * {@inheritDoc}
96 */
97 public abstract int hashCode();
98
99 /**
100 * {@inheritDoc}
101 */
102 public abstract String toString();
103
104 // modifiers
105 // ------------------------------------------------------------------------
106 /**
107 * Add a BinaryPredicate to the list
108 * @param p BinaryPredicate to add
109 */
110 protected void addBinaryPredicate(BinaryPredicate<? super L, ? super R> p) {
111 if (p == null) {
112 throw new IllegalArgumentException("Cannot add null BinaryPredicate");
113 }
114 list.add(p);
115 }
116
117 // protected
118 // ------------------------------------------------------------------------
119 /**
120 * Get the "live" list of contained {@link BinaryPredicate} instances.
121 * @return List
122 */
123 protected List<BinaryPredicate<? super L, ? super R>> getBinaryPredicateList() {
124 return list;
125 }
126
127 /**
128 * Learn whether another list is equal to this one.
129 * @param that BaseBinaryPredicateList to test
130 * @return boolean
131 */
132 protected boolean getBinaryPredicateListEquals(BaseBinaryPredicateList<?, ?> that) {
133 return (null != that && this.list.equals(that.list));
134 }
135
136 /**
137 * Get a hashCode for the list.
138 * @return int
139 */
140 protected int getBinaryPredicateListHashCode() {
141 return list.hashCode();
142 }
143
144 /**
145 * Get a toString for the list.
146 * @return String
147 */
148 protected String getBinaryPredicateListToString() {
149 return String.valueOf(list);
150 }
151
152 }