function-composition/src/main/java/com/iluwatar/function/composition/FunctionComposer.java - master - githubmirror/java-design-patterns

function-composition/src/main/java/com/iluwatar/function/composition/FunctionComposer.java

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Ilkka Seppälä

docs: update function composition pattern

12 апр 2025, 16:11

12 апр 2025, 16:118ca487e

/*
 * This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
 *
 * The MIT License
 * Copyright © 2014-2022 Ilkka Seppälä
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.iluwatar.function.composition;

import java.util.function.Function;

/**
 * Class for composing functions using the Function Composition pattern. Provides a static method to
 * compose two functions using the 'andThen' method.
 */
public class FunctionComposer {

  private FunctionComposer() {}

  /**
   * Composes two functions where the output of the first function becomes the input of the second
   * function.
   *
   * @param f1 the first function to apply
   * @param f2 the second function to apply after the first
   * @return a composed function that applies f1 and then f2
   */
  public static Function<Integer, Integer> composeFunctions(
      Function<Integer, Integer> f1, Function<Integer, Integer> f2) {
    return f1.andThen(f2);
  }
}