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 org.apache.commons.functor.BinaryProcedure;
20 import org.apache.commons.functor.Procedure;
21 import org.apache.commons.lang3.Validate;
22
23 /**
24 * Adapts a
25 * {@link BinaryProcedure BinaryProcedure}
26 * to the
27 * {@link Procedure Procedure} interface
28 * using a constant left-side argument.
29 *
30 * @param <A> the argument type.
31 * @version $Revision: 1537906 $ $Date: 2013-11-01 12:47:33 +0100 (Fr, 01 Nov 2013) $
32 */
33 public final class RightBoundProcedure<A> implements Procedure<A> {
34 /** The {@link BinaryProcedure BinaryProcedure} I'm wrapping. */
35 private final BinaryProcedure<? super A, Object> procedure;
36 /** The parameter to pass to {@code procedure}. */
37 private final Object param;
38
39 /**
40 * Create a new RightBoundProcedure.
41 * @param <R> bound arg type
42 * @param procedure the procedure to adapt
43 * @param arg the constant argument to use
44 */
45 @SuppressWarnings("unchecked")
46 public <R> RightBoundProcedure(BinaryProcedure<? super A, ? super R> procedure, R arg) {
47 this.procedure =
48 (BinaryProcedure<? super A, Object>) Validate.notNull(procedure,
49 "BinaryProcedure argument was null");
50 this.param = arg;
51 }
52
53 /**
54 * {@inheritDoc}
55 */
56 public void run(A obj) {
57 procedure.run(obj, param);
58 }
59
60 /**
61 * {@inheritDoc}
62 */
63 @Override
64 public boolean equals(Object obj) {
65 if (obj == this) {
66 return true;
67 }
68 if (!(obj instanceof RightBoundProcedure<?>)) {
69 return false;
70 }
71 RightBoundProcedure<?> that = (RightBoundProcedure<?>) obj;
72 return this.procedure.equals(that.procedure)
73 && (null == param ? null == that.param : param.equals(that.param));
74 }
75
76 /**
77 * {@inheritDoc}
78 */
79 @Override
80 public int hashCode() {
81 int hash = "RightBoundProcedure".hashCode();
82 hash <<= 2;
83 hash ^= procedure.hashCode();
84 if (null != param) {
85 hash <<= 2;
86 hash ^= param.hashCode();
87 }
88 return hash;
89 }
90
91 /**
92 * {@inheritDoc}
93 */
94 @Override
95 public String toString() {
96 return "RightBoundProcedure<" + procedure + "(?," + param + ")>";
97 }
98
99 /**
100 * Get a Procedure from <code>procedure</code>.
101 * @param <L> the left argument type.
102 * @param <R> the right argument type.
103 * @param procedure to adapt
104 * @param arg right side argument
105 * @return RightBoundProcedure
106 */
107 public static <L, R> RightBoundProcedure<L> bind(BinaryProcedure<? super L, ? super R> procedure, R arg) {
108 return null == procedure ? null : new RightBoundProcedure<L>(procedure, arg);
109 }
110
111 }