Java tutorial
/* * Copyright 2010-2013 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 org.killbill.billing.subscription.alignment; import org.joda.time.DateTime; import org.killbill.billing.catalog.api.Duration; public class BaseAligner { protected DateTime addDuration(final DateTime input, final Duration duration) { return addOrRemoveDuration(input, duration, true); } protected DateTime removeDuration(final DateTime input, final Duration duration) { return addOrRemoveDuration(input, duration, false); } private DateTime addOrRemoveDuration(final DateTime input, final Duration duration, boolean add) { DateTime result = input; switch (duration.getUnit()) { case DAYS: result = add ? result.plusDays(duration.getNumber()) : result.minusDays(duration.getNumber()); ; break; case MONTHS: result = add ? result.plusMonths(duration.getNumber()) : result.minusMonths(duration.getNumber()); break; case YEARS: result = add ? result.plusYears(duration.getNumber()) : result.minusYears(duration.getNumber()); break; case UNLIMITED: default: throw new RuntimeException("Trying to move to unlimited time period"); } return result; } }