/*

 * 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.Transformer;

/**

 * Transformer implementation that returns a clone of the input object.

 * <p>

 * Clone is performed using <code>PrototypeFactory.prototypeFactory(input).create()</code>.

 * </p>

 * <p>

 * <b>WARNING:</b> from v4.1 onwards this class will <b>not</b> 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>

 *

 * @since 3.0

 */

public class CloneTransformer<T> implements Transformer<T, T> {

    /** Singleton predicate instance */

    @SuppressWarnings("rawtypes") // the singleton instance works for all types

    public static final Transformer INSTANCE = new CloneTransformer<>();

    /**

     * Factory returning the singleton instance.

     *

     * @param <T>  the type of the objects to be cloned

     * @return the singleton instance

     * @since 3.1

     */

    public static <T> Transformer<T, T> cloneTransformer() {

        return INSTANCE;

    }

    /**

     * Constructor.

     */

    private CloneTransformer() {

        super();

    }

    /**

     * Transforms the input to result by cloning it.

     *

     * @param input  the input object to transform

     * @return the transformed result

     */

    @Override

    public T transform(final T input) {

        if (input == null) {

            return null;

        }

        return PrototypeFactory.prototypeFactory(input).create();

    }

}