/* * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.util.function; import java.util.Objects; /** * Represents an operation on a single {@code long}-valued operand that produces * a {@code long}-valued result. This is the primitive type specialization of * {@link UnaryOperator} for {@code long}. * *

This is a functional interface * whose functional method is {@link #applyAsLong(long)}. * * @see UnaryOperator * @since 1.8 */ @FunctionalInterface public interface LongUnaryOperator { /** * Applies this operator to the given operand. * * @param operand the operand * @return the operator result */ long applyAsLong(long operand); /** * Returns a composed operator that first applies the {@code before} * operator to its input, and then applies this operator to the result. * If evaluation of either operator throws an exception, it is relayed to * the caller of the composed operator. * * @param before the operator to apply before this operator is applied * @return a composed operator that first applies the {@code before} * operator and then applies this operator * @throws NullPointerException if before is null * * @see #andThen(LongUnaryOperator) */ default LongUnaryOperator compose(LongUnaryOperator before) { Objects.requireNonNull(before); return (long v) -> applyAsLong(before.applyAsLong(v)); } /** * Returns a composed operator that first applies this operator to * its input, and then applies the {@code after} operator to the result. * If evaluation of either operator throws an exception, it is relayed to * the caller of the composed operator. * * @param after the operator to apply after this operator is applied * @return a composed operator that first applies this operator and then * applies the {@code after} operator * @throws NullPointerException if after is null * * @see #compose(LongUnaryOperator) */ default LongUnaryOperator andThen(LongUnaryOperator after) { Objects.requireNonNull(after); return (long t) -> after.applyAsLong(applyAsLong(t)); } /** * Returns a unary operator that always returns its input argument. * * @return a unary operator that always returns its input argument */ static LongUnaryOperator identity() { return t -> t; } }