org.apache.commons.collections4.functors.FactoryTransformer Maven / Gradle / Ivy
/*
* 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 java.io.Serializable;
import org.apache.commons.collections4.Factory;
import org.apache.commons.collections4.Transformer;
/**
* Transformer implementation that calls a Factory and returns the result.
*
* @since 3.0
* @version $Id: FactoryTransformer.java 1686855 2015-06-22 13:00:27Z tn $
*/
public class FactoryTransformer implements Transformer, Serializable {
/** Serial version UID */
private static final long serialVersionUID = -6817674502475353160L;
/** The factory to wrap */
private final Factory iFactory;
/**
* Factory method that performs validation.
*
* @param the input type
* @param the output type
* @param factory the factory to call, not null
* @return the factory
transformer
* @throws NullPointerException if the factory is null
*/
public static Transformer factoryTransformer(final Factory factory) {
if (factory == null) {
throw new NullPointerException("Factory must not be null");
}
return new FactoryTransformer(factory);
}
/**
* Constructor that performs no validation.
* Use factoryTransformer
if you want that.
*
* @param factory the factory to call, not null
*/
public FactoryTransformer(final Factory factory) {
super();
iFactory = factory;
}
/**
* Transforms the input by ignoring the input and returning the result of
* calling the decorated factory.
*
* @param input the input object to transform
* @return the transformed result
*/
public O transform(final I input) {
return iFactory.create();
}
/**
* Gets the factory.
*
* @return the factory
* @since 3.1
*/
public Factory getFactory() {
return iFactory;
}
}