Here you can find the source of roundDown(final LocalDate dateTime, final TemporalUnit temporalUnit, final int size)
private static LocalDate roundDown(final LocalDate dateTime, final TemporalUnit temporalUnit, final int size)
//package com.java2s; /*/* w w w .j a v a 2s . c o m*/ * Copyright 2017 Crown Copyright * * Licensed 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. */ import java.time.LocalDate; import java.time.temporal.TemporalUnit; public class Main { private static LocalDate roundDown(final LocalDate dateTime, final TemporalUnit temporalUnit, final int size) { LocalDate epoch = LocalDate.ofEpochDay(0); long count = temporalUnit.between(epoch, dateTime); long round = count / size * size; long diff = round - count; return dateTime.plus(diff, temporalUnit); } }