/*

 * 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;

/**

 * Defines a functor interface implemented by classes that do something.

 * <p>

 * A <code>Closure</code> represents a block of code which is executed from

 * inside some block, function or iteration. It operates an input object.

 * </p>

 * <p>

 * Standard implementations of common closures are provided by

 * {@link ClosureUtils}. These include method invocation and for/while loops.

 * </p>

 *

 * @param <T> the type that the closure acts on

 * @since 1.0

 */

@FunctionalInterface

public interface Closure<T> {

    /**

     * Performs an action on the specified input object.

     *

     * @param input  the input to execute on

     * @throws ClassCastException (runtime) if the input is the wrong class

     * @throws IllegalArgumentException (runtime) if the input is invalid

     * @throws FunctorException (runtime) if any other error occurs

     */

    void execute(T input);

}