001/*
002 *  Copyright 2001-2005 Stephen Colebourne
003 *
004 *  Licensed under the Apache License, Version 2.0 (the "License");
005 *  you may not use this file except in compliance with the License.
006 *  You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 *  Unless required by applicable law or agreed to in writing, software
011 *  distributed under the License is distributed on an "AS IS" BASIS,
012 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 *  See the License for the specific language governing permissions and
014 *  limitations under the License.
015 */
016package org.joda.time.format;
017
018/**
019 * Factory that creates instances of PeriodFormatter for the ISO8601 standard.
020 * <p>
021 * Period formatting is performed by the {@link PeriodFormatter} class.
022 * Three classes provide factory methods to create formatters, and this is one.
023 * The others are {@link PeriodFormat} and {@link PeriodFormatterBuilder}.
024 * <p>
025 * ISOPeriodFormat is thread-safe and immutable, and the formatters it
026 * returns are as well.
027 *
028 * @author Brian S O'Neill
029 * @since 1.0
030 * @see PeriodFormat
031 * @see PeriodFormatterBuilder
032 */
033public class ISOPeriodFormat {
034
035    /** Cache of standard format. */
036    private static PeriodFormatter cStandard;
037    /** Cache of alternate months format. */
038    private static PeriodFormatter cAlternate;
039    /** Cache of alternate extended months format. */
040    private static PeriodFormatter cAlternateExtended;
041    /** Cache of alternate weeks format. */
042    private static PeriodFormatter cAlternateWithWeeks;
043    /** Cache of alternate extended weeks format. */
044    private static PeriodFormatter cAlternateExtendedWihWeeks;
045
046    /**
047     * Constructor.
048     *
049     * @since 1.1 (previously private)
050     */
051    protected ISOPeriodFormat() {
052        super();
053    }
054
055    //-----------------------------------------------------------------------
056    /**
057     * The standard ISO format - PyYmMwWdDThHmMsS.
058     * Milliseconds are not output.
059     * Note that the ISO8601 standard actually indicates weeks should not
060     * be shown if any other field is present and vice versa.
061     * 
062     * @return the formatter
063     */
064    public static PeriodFormatter standard() {
065        if (cStandard == null) {
066            cStandard = new PeriodFormatterBuilder()
067                .appendLiteral("P")
068                .appendYears()
069                .appendSuffix("Y")
070                .appendMonths()
071                .appendSuffix("M")
072                .appendWeeks()
073                .appendSuffix("W")
074                .appendDays()
075                .appendSuffix("D")
076                .appendSeparatorIfFieldsAfter("T")
077                .appendHours()
078                .appendSuffix("H")
079                .appendMinutes()
080                .appendSuffix("M")
081                .appendSecondsWithOptionalMillis()
082                .appendSuffix("S")
083                .toFormatter();
084        }
085        return cStandard;
086    }
087
088    /**
089     * The alternate ISO format, PyyyymmddThhmmss, which excludes weeks.
090     * <p>
091     * Even if weeks are present in the period, they are not output.
092     * Fractional seconds (milliseconds) will appear if required.
093     * 
094     * @return the formatter
095     */
096    public static PeriodFormatter alternate() {
097        if (cAlternate == null) {
098            cAlternate = new PeriodFormatterBuilder()
099                .appendLiteral("P")
100                .printZeroAlways()
101                .minimumPrintedDigits(4)
102                .appendYears()
103                .minimumPrintedDigits(2)
104                .appendMonths()
105                .appendDays()
106                .appendSeparatorIfFieldsAfter("T")
107                .appendHours()
108                .appendMinutes()
109                .appendSecondsWithOptionalMillis()
110                .toFormatter();
111        }
112        return cAlternate;
113    }
114
115    /**
116     * The alternate ISO format, Pyyyy-mm-ddThh:mm:ss, which excludes weeks.
117     * <p>
118     * Even if weeks are present in the period, they are not output.
119     * Fractional seconds (milliseconds) will appear if required.
120     * 
121     * @return the formatter
122     */
123    public static PeriodFormatter alternateExtended() {
124        if (cAlternateExtended == null) {
125            cAlternateExtended = new PeriodFormatterBuilder()
126                .appendLiteral("P")
127                .printZeroAlways()
128                .minimumPrintedDigits(4)
129                .appendYears()
130                .appendSeparator("-")
131                .minimumPrintedDigits(2)
132                .appendMonths()
133                .appendSeparator("-")
134                .appendDays()
135                .appendSeparatorIfFieldsAfter("T")
136                .appendHours()
137                .appendSeparator(":")
138                .appendMinutes()
139                .appendSeparator(":")
140                .appendSecondsWithOptionalMillis()
141                .toFormatter();
142        }
143        return cAlternateExtended;
144    }
145
146    /**
147     * The alternate ISO format, PyyyyWwwddThhmmss, which excludes months.
148     * <p>
149     * Even if months are present in the period, they are not output.
150     * Fractional seconds (milliseconds) will appear if required.
151     * 
152     * @return the formatter
153     */
154    public static PeriodFormatter alternateWithWeeks() {
155        if (cAlternateWithWeeks == null) {
156            cAlternateWithWeeks = new PeriodFormatterBuilder()
157                .appendLiteral("P")
158                .printZeroAlways()
159                .minimumPrintedDigits(4)
160                .appendYears()
161                .minimumPrintedDigits(2)
162                .appendPrefix("W")
163                .appendWeeks()
164                .appendDays()
165                .appendSeparatorIfFieldsAfter("T")
166                .appendHours()
167                .appendMinutes()
168                .appendSecondsWithOptionalMillis()
169                .toFormatter();
170        }
171        return cAlternateWithWeeks;
172    }
173
174    /**
175     * The alternate ISO format, Pyyyy-Www-ddThh:mm:ss, which excludes months.
176     * <p>
177     * Even if months are present in the period, they are not output.
178     * Fractional seconds (milliseconds) will appear if required.
179     * 
180     * @return the formatter
181     */
182    public static PeriodFormatter alternateExtendedWithWeeks() {
183        if (cAlternateExtendedWihWeeks == null) {
184            cAlternateExtendedWihWeeks = new PeriodFormatterBuilder()
185                .appendLiteral("P")
186                .printZeroAlways()
187                .minimumPrintedDigits(4)
188                .appendYears()
189                .appendSeparator("-")
190                .minimumPrintedDigits(2)
191                .appendPrefix("W")
192                .appendWeeks()
193                .appendSeparator("-")
194                .appendDays()
195                .appendSeparatorIfFieldsAfter("T")
196                .appendHours()
197                .appendSeparator(":")
198                .appendMinutes()
199                .appendSeparator(":")
200                .appendSecondsWithOptionalMillis()
201                .toFormatter();
202        }
203        return cAlternateExtendedWihWeeks;
204    }
205
206}