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.collections4.functors;
18
19 import org.apache.commons.collections4.Closure;
20
21 /**
22 * Closure implementation that calls another closure n times, like a for loop.
23 * <p>
24 * <b>WARNING:</b> from v4.1 onwards this class will <b>not</b> be serializable anymore
25 * in order to prevent potential remote code execution exploits. Please refer to
26 * <a href="https://issues.apache.org/jira/browse/COLLECTIONS-580">COLLECTIONS-580</a>
27 * for more details.
28 * </p>
29 *
30 * @since 3.0
31 */
32 public class ForClosure<E> implements Closure<E> {
33
34 /**
35 * Factory method that performs validation.
36 * <p>
37 * A null closure or zero count returns the {@code NOPClosure}.
38 * A count of one returns the specified closure.
39 *
40 * @param <E> the type that the closure acts on
41 * @param count the number of times to execute the closure
42 * @param closure the closure to execute, not null
43 * @return the {@code for} closure
44 */
45 @SuppressWarnings("unchecked")
46 public static <E> Closure<E> forClosure(final int count, final Closure<? super E> closure) {
47 if (count <= 0 || closure == null) {
48 return NOPClosure.<E>nopClosure();
49 }
50 if (count == 1) {
51 return (Closure<E>) closure;
52 }
53 return new ForClosure<>(count, closure);
54 }
55 /** The number of times to loop */
56 private final int iCount;
57
58 /** The closure to call */
59 private final Closure<? super E> iClosure;
60
61 /**
62 * Constructor that performs no validation.
63 * Use {@code forClosure} if you want that.
64 *
65 * @param count the number of times to execute the closure
66 * @param closure the closure to execute, not null
67 */
68 public ForClosure(final int count, final Closure<? super E> closure) {
69 iCount = count;
70 iClosure = closure;
71 }
72
73 /**
74 * Executes the closure {@code count} times.
75 *
76 * @param input the input object
77 */
78 @Override
79 public void execute(final E input) {
80 for (int i = 0; i < iCount; i++) {
81 iClosure.execute(input);
82 }
83 }
84
85 /**
86 * Gets the closure.
87 *
88 * @return the closure
89 * @since 3.1
90 */
91 public Closure<? super E> getClosure() {
92 return iClosure;
93 }
94
95 /**
96 * Gets the count.
97 *
98 * @return the count
99 * @since 3.1
100 */
101 public int getCount() {
102 return iCount;
103 }
104
105 }