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/*
* 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.collections.functors;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import org.apache.commons.collections.Closure;
/**
* Closure implementation that calls another closure n times, like a for loop.
*
* WARNING: from v3.2.2 onwards this class will throw an
* {@link UnsupportedOperationException} when trying to serialize or
* de-serialize an instance to prevent potential remote code execution exploits.
*
* In order to re-enable serialization support for {@code ForClosure}
* the following system property can be used (via -Dproperty=true):
*
* org.apache.commons.collections.enableUnsafeSerialization
*
*
* @since Commons Collections 3.0
* @version $Revision: 1713845 $ $Date: 2015-11-11 15:02:16 +0100 (Wed, 11 Nov 2015) $
*
* @author Stephen Colebourne
*/
public class ForClosure implements Closure, Serializable {
/** Serial version UID */
private static final long serialVersionUID = -1190120533393621674L;
/** The number of times to loop */
private final int iCount;
/** The closure to call */
private final Closure iClosure;
/**
* Factory method that performs validation.
*
* A null closure or zero count returns the NOPClosure.
* A count of one returns the specified closure.
*
* @param count the number of times to execute the closure
* @param closure the closure to execute, not null
* @return the for closure
*/
public static Closure getInstance(int count, Closure closure) {
if (count <= 0 || closure == null) {
return NOPClosure.INSTANCE;
}
if (count == 1) {
return closure;
}
return new ForClosure(count, closure);
}
/**
* Constructor that performs no validation.
* Use getInstance if you want that.
*
* @param count the number of times to execute the closure
* @param closure the closure to execute, not null
*/
public ForClosure(int count, Closure closure) {
super();
iCount = count;
iClosure = closure;
}
/**
* Executes the closure count times.
*
* @param input the input object
*/
public void execute(Object input) {
for (int i = 0; i < iCount; i++) {
iClosure.execute(input);
}
}
/**
* Gets the closure.
*
* @return the closure
* @since Commons Collections 3.1
*/
public Closure getClosure() {
return iClosure;
}
/**
* Gets the count.
*
* @return the count
* @since Commons Collections 3.1
*/
public int getCount() {
return iCount;
}
/**
* Overrides the default writeObject implementation to prevent
* serialization (see COLLECTIONS-580).
*/
private void writeObject(ObjectOutputStream os) throws IOException {
FunctorUtils.checkUnsafeSerialization(ForClosure.class);
os.defaultWriteObject();
}
/**
* Overrides the default readObject implementation to prevent
* de-serialization (see COLLECTIONS-580).
*/
private void readObject(ObjectInputStream is) throws ClassNotFoundException, IOException {
FunctorUtils.checkUnsafeSerialization(ForClosure.class);
is.defaultReadObject();
}
}