ForClosure.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.collections4.functors;
import org.apache.commons.collections4.Closure;
/**
* Closure implementation that calls another closure n times, like a for loop.
* <p>
* <strong>WARNING:</strong> from v4.1 onwards this class will <strong>not</strong> be serializable anymore
* in order to prevent potential remote code execution exploits. Please refer to
* <a href="https://issues.apache.org/jira/browse/COLLECTIONS-580">COLLECTIONS-580</a>
* for more details.
* </p>
*
* @param <T> the type of the input to the operation.
* @since 3.0
*/
public class ForClosure<T> implements Closure<T> {
/**
* Factory method that performs validation.
* <p>
* A null closure or zero count returns the {@code NOPClosure}.
* A count of one returns the specified closure.
*
* @param <E> the type that the closure acts on
* @param count the number of times to execute the closure
* @param closure the closure to execute, not null
* @return the {@code for} closure
*/
@SuppressWarnings("unchecked")
public static <E> Closure<E> forClosure(final int count, final Closure<? super E> closure) {
if (count <= 0 || closure == null) {
return NOPClosure.<E>nopClosure();
}
if (count == 1) {
return (Closure<E>) closure;
}
return new ForClosure<>(count, closure);
}
/** The number of times to loop */
private final int iCount;
/** The closure to call */
private final Closure<? super T> iClosure;
/**
* Constructor that performs no validation.
* Use {@code forClosure} if you want that.
*
* @param count the number of times to execute the closure
* @param closure the closure to execute, not null
*/
public ForClosure(final int count, final Closure<? super T> closure) {
iCount = count;
iClosure = closure;
}
/**
* Executes the closure {@code count} times.
*
* @param input the input object
*/
@Override
public void execute(final T input) {
for (int i = 0; i < iCount; i++) {
iClosure.accept(input);
}
}
/**
* Gets the closure.
*
* @return the closure
* @since 3.1
*/
public Closure<? super T> getClosure() {
return iClosure;
}
/**
* Gets the count.
*
* @return the count
* @since 3.1
*/
public int getCount() {
return iCount;
}
}