Java tutorial
/* * Copyright 2001-2005 Stephen Colebourne * * 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. */ package org.joda.time.format; /** * Factory that creates instances of PeriodFormatter for the ISO8601 standard. * <p> * Period formatting is performed by the {@link PeriodFormatter} class. * Three classes provide factory methods to create formatters, and this is one. * The others are {@link PeriodFormat} and {@link PeriodFormatterBuilder}. * <p> * ISOPeriodFormat is thread-safe and immutable, and the formatters it * returns are as well. * * @author Brian S O'Neill * @since 1.0 * @see PeriodFormat * @see PeriodFormatterBuilder */ public class ISOPeriodFormat { /** Cache of standard format. */ private static PeriodFormatter cStandard; /** Cache of alternate months format. */ private static PeriodFormatter cAlternate; /** Cache of alternate extended months format. */ private static PeriodFormatter cAlternateExtended; /** Cache of alternate weeks format. */ private static PeriodFormatter cAlternateWithWeeks; /** Cache of alternate extended weeks format. */ private static PeriodFormatter cAlternateExtendedWihWeeks; /** * Constructor. * * @since 1.1 (previously private) */ protected ISOPeriodFormat() { super(); } //----------------------------------------------------------------------- /** * The standard ISO format - PyYmMwWdDThHmMsS. * Milliseconds are not output. * Note that the ISO8601 standard actually indicates weeks should not * be shown if any other field is present and vice versa. * * @return the formatter */ public static PeriodFormatter standard() { if (cStandard == null) { cStandard = new PeriodFormatterBuilder().appendLiteral("P").appendYears().appendSuffix("Y") .appendMonths().appendSuffix("M").appendWeeks().appendSuffix("W").appendDays().appendSuffix("D") .appendSeparatorIfFieldsAfter("T").appendHours().appendSuffix("H").appendMinutes() .appendSuffix("M").appendSecondsWithOptionalMillis().appendSuffix("S").toFormatter(); } return cStandard; } /** * The alternate ISO format, PyyyymmddThhmmss, which excludes weeks. * <p> * Even if weeks are present in the period, they are not output. * Fractional seconds (milliseconds) will appear if required. * * @return the formatter */ public static PeriodFormatter alternate() { if (cAlternate == null) { cAlternate = new PeriodFormatterBuilder().appendLiteral("P").printZeroAlways().minimumPrintedDigits(4) .appendYears().minimumPrintedDigits(2).appendMonths().appendDays() .appendSeparatorIfFieldsAfter("T").appendHours().appendMinutes() .appendSecondsWithOptionalMillis().toFormatter(); } return cAlternate; } /** * The alternate ISO format, Pyyyy-mm-ddThh:mm:ss, which excludes weeks. * <p> * Even if weeks are present in the period, they are not output. * Fractional seconds (milliseconds) will appear if required. * * @return the formatter */ public static PeriodFormatter alternateExtended() { if (cAlternateExtended == null) { cAlternateExtended = new PeriodFormatterBuilder().appendLiteral("P").printZeroAlways() .minimumPrintedDigits(4).appendYears().appendSeparator("-").minimumPrintedDigits(2) .appendMonths().appendSeparator("-").appendDays().appendSeparatorIfFieldsAfter("T") .appendHours().appendSeparator(":").appendMinutes().appendSeparator(":") .appendSecondsWithOptionalMillis().toFormatter(); } return cAlternateExtended; } /** * The alternate ISO format, PyyyyWwwddThhmmss, which excludes months. * <p> * Even if months are present in the period, they are not output. * Fractional seconds (milliseconds) will appear if required. * * @return the formatter */ public static PeriodFormatter alternateWithWeeks() { if (cAlternateWithWeeks == null) { cAlternateWithWeeks = new PeriodFormatterBuilder().appendLiteral("P").printZeroAlways() .minimumPrintedDigits(4).appendYears().minimumPrintedDigits(2).appendPrefix("W").appendWeeks() .appendDays().appendSeparatorIfFieldsAfter("T").appendHours().appendMinutes() .appendSecondsWithOptionalMillis().toFormatter(); } return cAlternateWithWeeks; } /** * The alternate ISO format, Pyyyy-Www-ddThh:mm:ss, which excludes months. * <p> * Even if months are present in the period, they are not output. * Fractional seconds (milliseconds) will appear if required. * * @return the formatter */ public static PeriodFormatter alternateExtendedWithWeeks() { if (cAlternateExtendedWihWeeks == null) { cAlternateExtendedWihWeeks = new PeriodFormatterBuilder().appendLiteral("P").printZeroAlways() .minimumPrintedDigits(4).appendYears().appendSeparator("-").minimumPrintedDigits(2) .appendPrefix("W").appendWeeks().appendSeparator("-").appendDays() .appendSeparatorIfFieldsAfter("T").appendHours().appendSeparator(":").appendMinutes() .appendSeparator(":").appendSecondsWithOptionalMillis().toFormatter(); } return cAlternateExtendedWihWeeks; } }