Java tutorial
/* * Copyright 2010-2011 Ning, Inc. * * Ning 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 com.ning.billing.util.clock; import java.util.ArrayList; import java.util.List; import org.joda.time.DateTime; import org.joda.time.DateTimeZone; import org.joda.time.LocalDate; import com.ning.billing.catalog.api.Duration; public class DefaultClock implements Clock { @Override public DateTime getNow(final DateTimeZone tz) { final DateTime result = new DateTime(tz); return truncateMs(result); } @Override public DateTime getUTCNow() { return getNow(DateTimeZone.UTC); } @Override public LocalDate getUTCToday() { return getToday(DateTimeZone.UTC); } @Override public LocalDate getToday(final DateTimeZone timeZone) { return new LocalDate(getUTCNow(), DateTimeZone.UTC); } public static DateTime toUTCDateTime(final DateTime input) { if (input == null) { return null; } final DateTime result = input.toDateTime(DateTimeZone.UTC); return truncateMs(result); } public static DateTime truncateMs(final DateTime input) { return input.minus(input.getMillisOfSecond()); } public static DateTime addOrRemoveDuration(final DateTime input, final List<Duration> durations, final boolean add) { DateTime result = input; for (final Duration cur : durations) { switch (cur.getUnit()) { case DAYS: result = add ? result.plusDays(cur.getNumber()) : result.minusDays(cur.getNumber()); break; case MONTHS: result = add ? result.plusMonths(cur.getNumber()) : result.minusMonths(cur.getNumber()); break; case YEARS: result = add ? result.plusYears(cur.getNumber()) : result.minusYears(cur.getNumber()); break; case UNLIMITED: default: throw new RuntimeException("Trying to move to unlimited time period"); } } return result; } public static DateTime addDuration(final DateTime input, final List<Duration> durations) { return addOrRemoveDuration(input, durations, true); } public static DateTime removeDuration(final DateTime input, final List<Duration> durations) { return addOrRemoveDuration(input, durations, false); } public static DateTime addDuration(final DateTime input, final Duration duration) { final List<Duration> list = new ArrayList<Duration>(); list.add(duration); return addOrRemoveDuration(input, list, true); } public static DateTime removeDuration(final DateTime input, final Duration duration) { final List<Duration> list = new ArrayList<Duration>(); list.add(duration); return addOrRemoveDuration(input, list, false); } }