001/* 002 * Units of Measurement Reference Implementation 003 * Copyright (c) 2005-2020, Units of Measurement project. 004 * 005 * All rights reserved. 006 * 007 * Redistribution and use in source and binary forms, with or without modification, 008 * are permitted provided that the following conditions are met: 009 * 010 * 1. Redistributions of source code must retain the above copyright notice, 011 * this list of conditions and the following disclaimer. 012 * 013 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions 014 * and the following disclaimer in the documentation and/or other materials provided with the distribution. 015 * 016 * 3. Neither the name of JSR-385, Indriya nor the names of their contributors may be used to endorse or promote products 017 * derived from this software without specific prior written permission. 018 * 019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 020 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 021 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 022 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE 023 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 026 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 028 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 029 */ 030package tech.units.indriya.function; 031 032import java.util.function.BiPredicate; 033import java.util.function.BinaryOperator; 034 035import tech.units.indriya.internal.function.simplify.UnitCompositionHandlerYieldingNormalForm; 036 037/** 038 * Functional interface for handling the composition (concatenation) of two unit converters. 039 * 040 * @author Andi Huber 041 * @author Werner Keil 042 * @version 1.2 043 * @since 2.0 044 */ 045public interface ConverterCompositionHandler { 046 047 /** 048 * Takes two converters {@code left}, {@code right} and returns a (not necessarily new) 049 * converter that is equivalent to the mathematical composition of these: 050 * <p> 051 * compose(left, right) === left o right 052 * 053 * <p> 054 * Implementation Note: Instead of using AbstractConverter as parameter 055 * and result types, this could be generalized to UnitConverter, but that 056 * would require some careful changes within AbstractConverter itself. 057 * 058 * @param left 059 * @param right 060 * @param canReduce 061 * @param doReduce 062 * @return 063 */ 064 public AbstractConverter compose( 065 AbstractConverter left, 066 AbstractConverter right, 067 BiPredicate<AbstractConverter, AbstractConverter> canReduce, 068 BinaryOperator<AbstractConverter> doReduce); 069 070 // -- FACTORIES (BUILT-IN) 071 072 /** 073 * @return the default built-in UnitCompositionHandler which is yielding a normal-form, 074 * required to decide whether two UnitConverters are equivalent 075 */ 076 public static ConverterCompositionHandler yieldingNormalForm() { 077 return new UnitCompositionHandlerYieldingNormalForm(); 078 } 079 080}