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com.xiaoleilu.hutool.date.format.FastDatePrinter Maven / Gradle / Ivy

package com.xiaoleilu.hutool.date.format;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.text.DateFormatSymbols;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.List;
import java.util.Locale;
import java.util.TimeZone;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

import com.xiaoleilu.hutool.date.DateException;

/**
 * {@link java.text.SimpleDateFormat} 的线程安全版本,用于将 {@link Date} 格式化输出
* Thanks to Apache Commons Lang 3.5 * * @since 2.16.2 * @see FastDateParser */ class FastDatePrinter extends AbstractDateBasic implements DatePrinter { private static final long serialVersionUID = -6305750172255764887L; /** 规则列表. */ private transient Rule[] rules; /** 估算最大长度. */ private transient int mMaxLengthEstimate; // Constructor // ----------------------------------------------------------------------- /** * 构造,内部使用
* * @param pattern 使用{@link java.text.SimpleDateFormat} 相同的日期格式 * @param timeZone 非空时区{@link TimeZone} * @param locale 非空{@link Locale} 日期地理位置 */ protected FastDatePrinter(final String pattern, final TimeZone timeZone, final Locale locale) { super(pattern, timeZone, locale); init(); } /** * 初始化 */ private void init() { final List rulesList = parsePattern(); rules = rulesList.toArray(new Rule[rulesList.size()]); int len = 0; for (int i = rules.length; --i >= 0;) { len += rules[i].estimateLength(); } mMaxLengthEstimate = len; } // Parse the pattern // ----------------------------------------------------------------------- /** *

* Returns a list of Rules given a pattern. *

* * @return a {@code List} of Rule objects * @throws IllegalArgumentException if pattern is invalid */ protected List parsePattern() { final DateFormatSymbols symbols = new DateFormatSymbols(locale); final List rules = new ArrayList<>(); final String[] ERAs = symbols.getEras(); final String[] months = symbols.getMonths(); final String[] shortMonths = symbols.getShortMonths(); final String[] weekdays = symbols.getWeekdays(); final String[] shortWeekdays = symbols.getShortWeekdays(); final String[] AmPmStrings = symbols.getAmPmStrings(); final int length = pattern.length(); final int[] indexRef = new int[1]; for (int i = 0; i < length; i++) { indexRef[0] = i; final String token = parseToken(pattern, indexRef); i = indexRef[0]; final int tokenLen = token.length(); if (tokenLen == 0) { break; } Rule rule; final char c = token.charAt(0); switch (c) { case 'G': // era designator (text) rule = new TextField(Calendar.ERA, ERAs); break; case 'y': // year (number) case 'Y': // week year if (tokenLen == 2) { rule = TwoDigitYearField.INSTANCE; } else { rule = selectNumberRule(Calendar.YEAR, tokenLen < 4 ? 4 : tokenLen); } if (c == 'Y') { rule = new WeekYear((NumberRule) rule); } break; case 'M': // month in year (text and number) if (tokenLen >= 4) { rule = new TextField(Calendar.MONTH, months); } else if (tokenLen == 3) { rule = new TextField(Calendar.MONTH, shortMonths); } else if (tokenLen == 2) { rule = TwoDigitMonthField.INSTANCE; } else { rule = UnpaddedMonthField.INSTANCE; } break; case 'd': // day in month (number) rule = selectNumberRule(Calendar.DAY_OF_MONTH, tokenLen); break; case 'h': // hour in am/pm (number, 1..12) rule = new TwelveHourField(selectNumberRule(Calendar.HOUR, tokenLen)); break; case 'H': // hour in day (number, 0..23) rule = selectNumberRule(Calendar.HOUR_OF_DAY, tokenLen); break; case 'm': // minute in hour (number) rule = selectNumberRule(Calendar.MINUTE, tokenLen); break; case 's': // second in minute (number) rule = selectNumberRule(Calendar.SECOND, tokenLen); break; case 'S': // millisecond (number) rule = selectNumberRule(Calendar.MILLISECOND, tokenLen); break; case 'E': // day in week (text) rule = new TextField(Calendar.DAY_OF_WEEK, tokenLen < 4 ? shortWeekdays : weekdays); break; case 'u': // day in week (number) rule = new DayInWeekField(selectNumberRule(Calendar.DAY_OF_WEEK, tokenLen)); break; case 'D': // day in year (number) rule = selectNumberRule(Calendar.DAY_OF_YEAR, tokenLen); break; case 'F': // day of week in month (number) rule = selectNumberRule(Calendar.DAY_OF_WEEK_IN_MONTH, tokenLen); break; case 'w': // week in year (number) rule = selectNumberRule(Calendar.WEEK_OF_YEAR, tokenLen); break; case 'W': // week in month (number) rule = selectNumberRule(Calendar.WEEK_OF_MONTH, tokenLen); break; case 'a': // am/pm marker (text) rule = new TextField(Calendar.AM_PM, AmPmStrings); break; case 'k': // hour in day (1..24) rule = new TwentyFourHourField(selectNumberRule(Calendar.HOUR_OF_DAY, tokenLen)); break; case 'K': // hour in am/pm (0..11) rule = selectNumberRule(Calendar.HOUR, tokenLen); break; case 'X': // ISO 8601 rule = Iso8601_Rule.getRule(tokenLen); break; case 'z': // time zone (text) if (tokenLen >= 4) { rule = new TimeZoneNameRule(timeZone, locale, TimeZone.LONG); } else { rule = new TimeZoneNameRule(timeZone, locale, TimeZone.SHORT); } break; case 'Z': // time zone (value) if (tokenLen == 1) { rule = TimeZoneNumberRule.INSTANCE_NO_COLON; } else if (tokenLen == 2) { rule = Iso8601_Rule.ISO8601_HOURS_COLON_MINUTES; } else { rule = TimeZoneNumberRule.INSTANCE_COLON; } break; case '\'': // literal text final String sub = token.substring(1); if (sub.length() == 1) { rule = new CharacterLiteral(sub.charAt(0)); } else { rule = new StringLiteral(sub); } break; default: throw new IllegalArgumentException("Illegal pattern component: " + token); } rules.add(rule); } return rules; } /** *

* Performs the parsing of tokens. *

* * @param pattern the pattern * @param indexRef index references * @return parsed token */ protected String parseToken(final String pattern, final int[] indexRef) { final StringBuilder buf = new StringBuilder(); int i = indexRef[0]; final int length = pattern.length(); char c = pattern.charAt(i); if (c >= 'A' && c <= 'Z' || c >= 'a' && c <= 'z') { // Scan a run of the same character, which indicates a time // pattern. buf.append(c); while (i + 1 < length) { final char peek = pattern.charAt(i + 1); if (peek == c) { buf.append(c); i++; } else { break; } } } else { // This will identify token as text. buf.append('\''); boolean inLiteral = false; for (; i < length; i++) { c = pattern.charAt(i); if (c == '\'') { if (i + 1 < length && pattern.charAt(i + 1) == '\'') { // '' is treated as escaped ' i++; buf.append(c); } else { inLiteral = !inLiteral; } } else if (!inLiteral && (c >= 'A' && c <= 'Z' || c >= 'a' && c <= 'z')) { i--; break; } else { buf.append(c); } } } indexRef[0] = i; return buf.toString(); } /** *

* Gets an appropriate rule for the padding required. *

* * @param field the field to get a rule for * @param padding the padding required * @return a new rule with the correct padding */ protected NumberRule selectNumberRule(final int field, final int padding) { switch (padding) { case 1: return new UnpaddedNumberField(field); case 2: return new TwoDigitNumberField(field); default: return new PaddedNumberField(field, padding); } } // Format methods // ----------------------------------------------------------------------- /** *

* Formats a {@code Date}, {@code Calendar} or {@code Long} (milliseconds) object. *

* * @param obj the object to format * @return The formatted value. */ String format(final Object obj) { if (obj instanceof Date) { return format((Date) obj); } else if (obj instanceof Calendar) { return format((Calendar) obj); } else if (obj instanceof Long) { return format(((Long) obj).longValue()); } else { throw new IllegalArgumentException("Unknown class: " + (obj == null ? "" : obj.getClass().getName())); } } @Override public String format(final long millis) { final Calendar c = Calendar.getInstance(timeZone, locale); c.setTimeInMillis(millis); return applyRulesToString(c); } @Override public String format(final Date date) { final Calendar c = Calendar.getInstance(timeZone, locale); c.setTime(date); return applyRulesToString(c); } @Override public String format(final Calendar calendar) { return format(calendar, new StringBuilder(mMaxLengthEstimate)).toString(); } @Override public B format(final long millis, final B buf) { final Calendar c = Calendar.getInstance(timeZone, locale); c.setTimeInMillis(millis); return applyRules(c, buf); } @Override public B format(final Date date, final B buf) { final Calendar c = Calendar.getInstance(timeZone, locale); c.setTime(date); return applyRules(c, buf); } @Override public B format(Calendar calendar, final B buf) { // do not pass in calendar directly, this will cause TimeZone of FastDatePrinter to be ignored if (!calendar.getTimeZone().equals(timeZone)) { calendar = (Calendar) calendar.clone(); calendar.setTimeZone(timeZone); } return applyRules(calendar, buf); } /** * Creates a String representation of the given Calendar by applying the rules of this printer to it. * * @param c the Calender to apply the rules to. * @return a String representation of the given Calendar. */ private String applyRulesToString(final Calendar c) { return applyRules(c, new StringBuilder(mMaxLengthEstimate)).toString(); } /** *

* Performs the formatting by applying the rules to the specified calendar. *

* * @param calendar the calendar to format * @param buf the buffer to format into * @param the Appendable class type, usually StringBuilder or StringBuffer. * @return the specified string buffer */ private B applyRules(final Calendar calendar, final B buf) { try { for (final Rule rule : this.rules) { rule.appendTo(buf, calendar); } } catch (final IOException e) { throw new DateException(e); } return buf; } /** *估算生成的日期字符串长度
* 实际生成的字符串长度小于或等于此值 * * @return 日期字符串长度 */ public int getMaxLengthEstimate() { return mMaxLengthEstimate; } // Serializing // ----------------------------------------------------------------------- /** * Create the object after serialization. This implementation reinitializes the transient properties. * * @param in ObjectInputStream from which the object is being deserialized. * @throws IOException if there is an IO issue. * @throws ClassNotFoundException if a class cannot be found. */ private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException { in.defaultReadObject(); init(); } /** * Appends two digits to the given buffer. * * @param buffer the buffer to append to. * @param value the value to append digits from. */ private static void appendDigits(final Appendable buffer, final int value) throws IOException { buffer.append((char) (value / 10 + '0')); buffer.append((char) (value % 10 + '0')); } private static final int MAX_DIGITS = 10; // log10(Integer.MAX_VALUE) ~= 9.3 /** * Appends all digits to the given buffer. * * @param buffer the buffer to append to. * @param value the value to append digits from. */ private static void appendFullDigits(final Appendable buffer, int value, int minFieldWidth) throws IOException { // specialized paths for 1 to 4 digits -> avoid the memory allocation from the temporary work array // see LANG-1248 if (value < 10000) { // less memory allocation path works for four digits or less int nDigits = 4; if (value < 1000) { --nDigits; if (value < 100) { --nDigits; if (value < 10) { --nDigits; } } } // left zero pad for (int i = minFieldWidth - nDigits; i > 0; --i) { buffer.append('0'); } switch (nDigits) { case 4: buffer.append((char) (value / 1000 + '0')); value %= 1000; case 3: if (value >= 100) { buffer.append((char) (value / 100 + '0')); value %= 100; } else { buffer.append('0'); } case 2: if (value >= 10) { buffer.append((char) (value / 10 + '0')); value %= 10; } else { buffer.append('0'); } case 1: buffer.append((char) (value + '0')); } } else { // more memory allocation path works for any digits // build up decimal representation in reverse final char[] work = new char[MAX_DIGITS]; int digit = 0; while (value != 0) { work[digit++] = (char) (value % 10 + '0'); value = value / 10; } // pad with zeros while (digit < minFieldWidth) { buffer.append('0'); --minFieldWidth; } // reverse while (--digit >= 0) { buffer.append(work[digit]); } } } // Rules // ----------------------------------------------------------------------- /** * 规则 */ private interface Rule { /** * Returns the estimated length of the result. * * @return the estimated length */ int estimateLength(); /** * Appends the value of the specified calendar to the output buffer based on the rule implementation. * * @param buf the output buffer * @param calendar calendar to be appended * @throws IOException if an I/O error occurs */ void appendTo(Appendable buf, Calendar calendar) throws IOException; } /** *

* Inner class defining a numeric rule. *

*/ private interface NumberRule extends Rule { /** * Appends the specified value to the output buffer based on the rule implementation. * * @param buffer the output buffer * @param value the value to be appended * @throws IOException if an I/O error occurs */ void appendTo(Appendable buffer, int value) throws IOException; } /** *

* Inner class to output a constant single character. *

*/ private static class CharacterLiteral implements Rule { private final char mValue; /** * Constructs a new instance of {@code CharacterLiteral} to hold the specified value. * * @param value the character literal */ CharacterLiteral(final char value) { mValue = value; } @Override public int estimateLength() { return 1; } @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { buffer.append(mValue); } } /** *

* Inner class to output a constant string. *

*/ private static class StringLiteral implements Rule { private final String mValue; /** * Constructs a new instance of {@code StringLiteral} to hold the specified value. * * @param value the string literal */ StringLiteral(final String value) { mValue = value; } /** * {@inheritDoc} */ @Override public int estimateLength() { return mValue.length(); } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { buffer.append(mValue); } } /** *

* Inner class to output one of a set of values. *

*/ private static class TextField implements Rule { private final int mField; private final String[] mValues; /** * Constructs an instance of {@code TextField} with the specified field and values. * * @param field the field * @param values the field values */ TextField(final int field, final String[] values) { mField = field; mValues = values; } /** * {@inheritDoc} */ @Override public int estimateLength() { int max = 0; for (int i = mValues.length; --i >= 0;) { final int len = mValues[i].length(); if (len > max) { max = len; } } return max; } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { buffer.append(mValues[calendar.get(mField)]); } } /** *

* Inner class to output an unpadded number. *

*/ private static class UnpaddedNumberField implements NumberRule { private final int mField; /** * Constructs an instance of {@code UnpadedNumberField} with the specified field. * * @param field the field */ UnpaddedNumberField(final int field) { mField = field; } /** * {@inheritDoc} */ @Override public int estimateLength() { return 4; } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { appendTo(buffer, calendar.get(mField)); } /** * {@inheritDoc} */ @Override public final void appendTo(final Appendable buffer, final int value) throws IOException { if (value < 10) { buffer.append((char) (value + '0')); } else if (value < 100) { appendDigits(buffer, value); } else { appendFullDigits(buffer, value, 1); } } } /** *

* Inner class to output an unpadded month. *

*/ private static class UnpaddedMonthField implements NumberRule { static final UnpaddedMonthField INSTANCE = new UnpaddedMonthField(); /** * Constructs an instance of {@code UnpaddedMonthField}. * */ UnpaddedMonthField() { super(); } /** * {@inheritDoc} */ @Override public int estimateLength() { return 2; } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { appendTo(buffer, calendar.get(Calendar.MONTH) + 1); } /** * {@inheritDoc} */ @Override public final void appendTo(final Appendable buffer, final int value) throws IOException { if (value < 10) { buffer.append((char) (value + '0')); } else { appendDigits(buffer, value); } } } /** *

* Inner class to output a padded number. *

*/ private static class PaddedNumberField implements NumberRule { private final int mField; private final int mSize; /** * Constructs an instance of {@code PaddedNumberField}. * * @param field the field * @param size size of the output field */ PaddedNumberField(final int field, final int size) { if (size < 3) { // Should use UnpaddedNumberField or TwoDigitNumberField. throw new IllegalArgumentException(); } mField = field; mSize = size; } /** * {@inheritDoc} */ @Override public int estimateLength() { return mSize; } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { appendTo(buffer, calendar.get(mField)); } /** * {@inheritDoc} */ @Override public final void appendTo(final Appendable buffer, final int value) throws IOException { appendFullDigits(buffer, value, mSize); } } /** *

* Inner class to output a two digit number. *

*/ private static class TwoDigitNumberField implements NumberRule { private final int mField; /** * Constructs an instance of {@code TwoDigitNumberField} with the specified field. * * @param field the field */ TwoDigitNumberField(final int field) { mField = field; } /** * {@inheritDoc} */ @Override public int estimateLength() { return 2; } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { appendTo(buffer, calendar.get(mField)); } /** * {@inheritDoc} */ @Override public final void appendTo(final Appendable buffer, final int value) throws IOException { if (value < 100) { appendDigits(buffer, value); } else { appendFullDigits(buffer, value, 2); } } } /** *

* Inner class to output a two digit year. *

*/ private static class TwoDigitYearField implements NumberRule { static final TwoDigitYearField INSTANCE = new TwoDigitYearField(); /** * Constructs an instance of {@code TwoDigitYearField}. */ TwoDigitYearField() { super(); } /** * {@inheritDoc} */ @Override public int estimateLength() { return 2; } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { appendTo(buffer, calendar.get(Calendar.YEAR) % 100); } /** * {@inheritDoc} */ @Override public final void appendTo(final Appendable buffer, final int value) throws IOException { appendDigits(buffer, value); } } /** *

* Inner class to output a two digit month. *

*/ private static class TwoDigitMonthField implements NumberRule { static final TwoDigitMonthField INSTANCE = new TwoDigitMonthField(); /** * Constructs an instance of {@code TwoDigitMonthField}. */ TwoDigitMonthField() { super(); } /** * {@inheritDoc} */ @Override public int estimateLength() { return 2; } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { appendTo(buffer, calendar.get(Calendar.MONTH) + 1); } /** * {@inheritDoc} */ @Override public final void appendTo(final Appendable buffer, final int value) throws IOException { appendDigits(buffer, value); } } /** *

* Inner class to output the twelve hour field. *

*/ private static class TwelveHourField implements NumberRule { private final NumberRule mRule; /** * Constructs an instance of {@code TwelveHourField} with the specified {@code NumberRule}. * * @param rule the rule */ TwelveHourField(final NumberRule rule) { mRule = rule; } /** * {@inheritDoc} */ @Override public int estimateLength() { return mRule.estimateLength(); } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { int value = calendar.get(Calendar.HOUR); if (value == 0) { value = calendar.getLeastMaximum(Calendar.HOUR) + 1; } mRule.appendTo(buffer, value); } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final int value) throws IOException { mRule.appendTo(buffer, value); } } /** *

* Inner class to output the twenty four hour field. *

*/ private static class TwentyFourHourField implements NumberRule { private final NumberRule mRule; /** * Constructs an instance of {@code TwentyFourHourField} with the specified {@code NumberRule}. * * @param rule the rule */ TwentyFourHourField(final NumberRule rule) { mRule = rule; } /** * {@inheritDoc} */ @Override public int estimateLength() { return mRule.estimateLength(); } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { int value = calendar.get(Calendar.HOUR_OF_DAY); if (value == 0) { value = calendar.getMaximum(Calendar.HOUR_OF_DAY) + 1; } mRule.appendTo(buffer, value); } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final int value) throws IOException { mRule.appendTo(buffer, value); } } /** *

* Inner class to output the numeric day in week. *

*/ private static class DayInWeekField implements NumberRule { private final NumberRule mRule; DayInWeekField(final NumberRule rule) { mRule = rule; } @Override public int estimateLength() { return mRule.estimateLength(); } @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { final int value = calendar.get(Calendar.DAY_OF_WEEK); mRule.appendTo(buffer, value != Calendar.SUNDAY ? value - 1 : 7); } @Override public void appendTo(final Appendable buffer, final int value) throws IOException { mRule.appendTo(buffer, value); } } /** *

* Inner class to output the numeric day in week. *

*/ private static class WeekYear implements NumberRule { private final NumberRule mRule; WeekYear(final NumberRule rule) { mRule = rule; } @Override public int estimateLength() { return mRule.estimateLength(); } @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { mRule.appendTo(buffer, calendar.getWeekYear()); } @Override public void appendTo(final Appendable buffer, final int value) throws IOException { mRule.appendTo(buffer, value); } } // ----------------------------------------------------------------------- private static final ConcurrentMap cTimeZoneDisplayCache = new ConcurrentHashMap<>(7); /** *

* Gets the time zone display name, using a cache for performance. *

* * @param tz the zone to query * @param daylight true if daylight savings * @param style the style to use {@code TimeZone.LONG} or {@code TimeZone.SHORT} * @param locale the locale to use * @return the textual name of the time zone */ static String getTimeZoneDisplay(final TimeZone tz, final boolean daylight, final int style, final Locale locale) { final TimeZoneDisplayKey key = new TimeZoneDisplayKey(tz, daylight, style, locale); String value = cTimeZoneDisplayCache.get(key); if (value == null) { // This is a very slow call, so cache the results. value = tz.getDisplayName(daylight, style, locale); final String prior = cTimeZoneDisplayCache.putIfAbsent(key, value); if (prior != null) { value = prior; } } return value; } /** *

* Inner class to output a time zone name. *

*/ private static class TimeZoneNameRule implements Rule { private final Locale mLocale; private final int mStyle; private final String mStandard; private final String mDaylight; /** * Constructs an instance of {@code TimeZoneNameRule} with the specified properties. * * @param timeZone the time zone * @param locale the locale * @param style the style */ TimeZoneNameRule(final TimeZone timeZone, final Locale locale, final int style) { mLocale = locale; mStyle = style; mStandard = getTimeZoneDisplay(timeZone, false, style, locale); mDaylight = getTimeZoneDisplay(timeZone, true, style, locale); } /** * {@inheritDoc} */ @Override public int estimateLength() { // We have no access to the Calendar object that will be passed to // appendTo so base estimate on the TimeZone passed to the // constructor return Math.max(mStandard.length(), mDaylight.length()); } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { final TimeZone zone = calendar.getTimeZone(); if (calendar.get(Calendar.DST_OFFSET) != 0) { buffer.append(getTimeZoneDisplay(zone, true, mStyle, mLocale)); } else { buffer.append(getTimeZoneDisplay(zone, false, mStyle, mLocale)); } } } /** *

* Inner class to output a time zone as a number {@code +/-HHMM} or {@code +/-HH:MM}. *

*/ private static class TimeZoneNumberRule implements Rule { static final TimeZoneNumberRule INSTANCE_COLON = new TimeZoneNumberRule(true); static final TimeZoneNumberRule INSTANCE_NO_COLON = new TimeZoneNumberRule(false); final boolean mColon; /** * Constructs an instance of {@code TimeZoneNumberRule} with the specified properties. * * @param colon add colon between HH and MM in the output if {@code true} */ TimeZoneNumberRule(final boolean colon) { mColon = colon; } /** * {@inheritDoc} */ @Override public int estimateLength() { return 5; } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { int offset = calendar.get(Calendar.ZONE_OFFSET) + calendar.get(Calendar.DST_OFFSET); if (offset < 0) { buffer.append('-'); offset = -offset; } else { buffer.append('+'); } final int hours = offset / (60 * 60 * 1000); appendDigits(buffer, hours); if (mColon) { buffer.append(':'); } final int minutes = offset / (60 * 1000) - 60 * hours; appendDigits(buffer, minutes); } } /** *

* Inner class to output a time zone as a number {@code +/-HHMM} or {@code +/-HH:MM}. *

*/ private static class Iso8601_Rule implements Rule { // Sign TwoDigitHours or Z static final Iso8601_Rule ISO8601_HOURS = new Iso8601_Rule(3); // Sign TwoDigitHours Minutes or Z static final Iso8601_Rule ISO8601_HOURS_MINUTES = new Iso8601_Rule(5); // Sign TwoDigitHours : Minutes or Z static final Iso8601_Rule ISO8601_HOURS_COLON_MINUTES = new Iso8601_Rule(6); /** * Factory method for Iso8601_Rules. * * @param tokenLen a token indicating the length of the TimeZone String to be formatted. * @return a Iso8601_Rule that can format TimeZone String of length {@code tokenLen}. If no such rule exists, an IllegalArgumentException will be thrown. */ static Iso8601_Rule getRule(final int tokenLen) { switch (tokenLen) { case 1: return Iso8601_Rule.ISO8601_HOURS; case 2: return Iso8601_Rule.ISO8601_HOURS_MINUTES; case 3: return Iso8601_Rule.ISO8601_HOURS_COLON_MINUTES; default: throw new IllegalArgumentException("invalid number of X"); } } final int length; /** * Constructs an instance of {@code Iso8601_Rule} with the specified properties. * * @param length The number of characters in output (unless Z is output) */ Iso8601_Rule(final int length) { this.length = length; } /** * {@inheritDoc} */ @Override public int estimateLength() { return length; } /** * {@inheritDoc} */ @Override public void appendTo(final Appendable buffer, final Calendar calendar) throws IOException { int offset = calendar.get(Calendar.ZONE_OFFSET) + calendar.get(Calendar.DST_OFFSET); if (offset == 0) { buffer.append("Z"); return; } if (offset < 0) { buffer.append('-'); offset = -offset; } else { buffer.append('+'); } final int hours = offset / (60 * 60 * 1000); appendDigits(buffer, hours); if (length < 5) { return; } if (length == 6) { buffer.append(':'); } final int minutes = offset / (60 * 1000) - 60 * hours; appendDigits(buffer, minutes); } } // ---------------------------------------------------------------------- /** *

* Inner class that acts as a compound key for time zone names. *

*/ private static class TimeZoneDisplayKey { private final TimeZone mTimeZone; private final int mStyle; private final Locale mLocale; /** * Constructs an instance of {@code TimeZoneDisplayKey} with the specified properties. * * @param timeZone the time zone * @param daylight adjust the style for daylight saving time if {@code true} * @param style the timezone style * @param locale the timezone locale */ TimeZoneDisplayKey(final TimeZone timeZone, final boolean daylight, final int style, final Locale locale) { mTimeZone = timeZone; if (daylight) { mStyle = style | 0x80000000; } else { mStyle = style; } mLocale = locale; } /** * {@inheritDoc} */ @Override public int hashCode() { return (mStyle * 31 + mLocale.hashCode()) * 31 + mTimeZone.hashCode(); } /** * {@inheritDoc} */ @Override public boolean equals(final Object obj) { if (this == obj) { return true; } if (obj instanceof TimeZoneDisplayKey) { final TimeZoneDisplayKey other = (TimeZoneDisplayKey) obj; return mTimeZone.equals(other.mTimeZone) && mStyle == other.mStyle && mLocale.equals(other.mLocale); } return false; } } }