FastDatePrinter.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.sqlite.date;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.text.DateFormat;
import java.text.DateFormatSymbols;
import java.text.FieldPosition;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.List;
import java.util.Locale;
import java.util.TimeZone;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
/**
* FastDatePrinter is a fast and thread-safe version of {@link java.text.SimpleDateFormat}.
*
* <p>To obtain a FastDatePrinter, use {@link FastDateFormat#getInstance(String, TimeZone, Locale)}
* or another variation of the factory methods of {@link FastDateFormat}.
*
* <p>Since FastDatePrinter is thread safe, you can use a static member instance: <code>
* private static final DatePrinter DATE_PRINTER = FastDateFormat.getInstance("yyyy-MM-dd");
* </code>
*
* <p>This class can be used as a direct replacement to {@code SimpleDateFormat} in most formatting
* situations. This class is especially useful in multi-threaded server environments. {@code
* SimpleDateFormat} is not thread-safe in any JDK version, nor will it be as Sun have closed the
* bug/RFE.
*
* <p>Only formatting is supported by this class, but all patterns are compatible with
* SimpleDateFormat (except time zones and some year patterns - see below).
*
* <p>Java 1.4 introduced a new pattern letter, {@code 'Z'}, to represent time zones in RFC822
* format (eg. {@code +0800} or {@code -1100}). This pattern letter can be used here (on all JDK
* versions).
*
* <p>In addition, the pattern {@code 'ZZ'} has been made to represent ISO 8601 full format time
* zones (eg. {@code +08:00} or {@code -11:00}). This introduces a minor incompatibility with Java
* 1.4, but at a gain of useful functionality.
*
* <p>Starting with JDK7, ISO 8601 support was added using the pattern {@code 'X'}. To maintain
* compatibility, {@code 'ZZ'} will continue to be supported, but using one of the {@code 'X'}
* formats is recommended.
*
* <p>Javadoc cites for the year pattern: <i>For formatting, if the number of pattern letters is 2,
* the year is truncated to 2 digits; otherwise it is interpreted as a number.</i> Starting with
* Java 1.7 a pattern of 'Y' or 'YYY' will be formatted as '2003', while it was '03' in former Java
* versions. FastDatePrinter implements the behavior of Java 7.
*
* @version $Id$
* @since 3.2
* @see FastDateParser
*/
public class FastDatePrinter implements DatePrinter, Serializable {
// A lot of the speed in this class comes from caching, but some comes
// from the special int to StringBuffer conversion.
//
// The following produces a padded 2 digit number:
// buffer.append((char)(value / 10 + '0'));
// buffer.append((char)(value % 10 + '0'));
//
// Note that the fastest append to StringBuffer is a single char (used here).
// Note that Integer.toString() is not called, the conversion is simply
// taking the value and adding (mathematically) the ASCII value for '0'.
// So, don't change this code! It works and is very fast.
/**
* Required for serialization support.
*
* @see java.io.Serializable
*/
private static final long serialVersionUID = 1L;
/** FULL locale dependent date or time style. */
public static final int FULL = DateFormat.FULL;
/** LONG locale dependent date or time style. */
public static final int LONG = DateFormat.LONG;
/** MEDIUM locale dependent date or time style. */
public static final int MEDIUM = DateFormat.MEDIUM;
/** SHORT locale dependent date or time style. */
public static final int SHORT = DateFormat.SHORT;
/** The pattern. */
private final String mPattern;
/** The time zone. */
private final TimeZone mTimeZone;
/** The locale. */
private final Locale mLocale;
/** The parsed rules. */
private transient Rule[] mRules;
/** The estimated maximum length. */
private transient int mMaxLengthEstimate;
// Constructor
// -----------------------------------------------------------------------
/**
* Constructs a new FastDatePrinter. Use {@link FastDateFormat#getInstance(String, TimeZone,
* Locale)} or another variation of the factory methods of {@link FastDateFormat} to get a
* cached FastDatePrinter instance.
*
* @param pattern {@link java.text.SimpleDateFormat} compatible pattern
* @param timeZone non-null time zone to use
* @param locale non-null locale to use
* @throws NullPointerException if pattern, timeZone, or locale is null.
*/
protected FastDatePrinter(final String pattern, final TimeZone timeZone, final Locale locale) {
mPattern = pattern;
mTimeZone = timeZone;
mLocale = locale;
init();
}
/** Initializes the instance for first use. */
private void init() {
final List<Rule> rulesList = parsePattern();
mRules = rulesList.toArray(new Rule[rulesList.size()]);
int len = 0;
for (int i = mRules.length; --i >= 0; ) {
len += mRules[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<Rule> parsePattern() {
final DateFormatSymbols symbols = new DateFormatSymbols(mLocale);
final List<Rule> rules = new ArrayList<Rule>();
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 = mPattern.length();
final int[] indexRef = new int[1];
for (int i = 0; i < length; i++) {
indexRef[0] = i;
final String token = parseToken(mPattern, 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)
if (tokenLen == 2) {
rule = TwoDigitYearField.INSTANCE;
} else {
rule = selectNumberRule(Calendar.YEAR, tokenLen < 4 ? 4 : tokenLen);
}
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 '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(mTimeZone, mLocale, TimeZone.LONG);
} else {
rule = new TimeZoneNameRule(mTimeZone, mLocale, TimeZone.SHORT);
}
break;
case 'Z': // time zone (value)
if (tokenLen == 1) {
rule = TimeZoneNumberRule.INSTANCE_NO_COLON;
} else if (tokenLen == 2) {
rule = TimeZoneNumberRule.INSTANCE_ISO_8601;
} 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
* @param toAppendTo the buffer to append to
* @param pos the position - ignored
* @return the buffer passed in
*/
public StringBuffer format(
final Object obj, final StringBuffer toAppendTo, final FieldPosition pos) {
if (obj instanceof Date) {
return format((Date) obj, toAppendTo);
} else if (obj instanceof Calendar) {
return format((Calendar) obj, toAppendTo);
} else if (obj instanceof Long) {
return format(((Long) obj).longValue(), toAppendTo);
} else {
throw new IllegalArgumentException(
"Unknown class: " + (obj == null ? "<null>" : obj.getClass().getName()));
}
}
/* (non-Javadoc)
* @see org.apache.commons.lang3.time.DatePrinter#format(long)
*/
public String format(final long millis) {
final Calendar c = newCalendar(); // hard code GregorianCalendar
c.setTimeInMillis(millis);
return applyRulesToString(c);
}
/**
* 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 StringBuffer(mMaxLengthEstimate)).toString();
}
/**
* Creation method for ne calender instances.
*
* @return a new Calendar instance.
*/
private GregorianCalendar newCalendar() {
// hard code GregorianCalendar
return new GregorianCalendar(mTimeZone, mLocale);
}
/* (non-Javadoc)
* @see org.apache.commons.lang3.time.DatePrinter#format(java.util.Date)
*/
public String format(final Date date) {
final Calendar c = newCalendar(); // hard code GregorianCalendar
c.setTime(date);
return applyRulesToString(c);
}
/* (non-Javadoc)
* @see org.apache.commons.lang3.time.DatePrinter#format(java.util.Calendar)
*/
public String format(final Calendar calendar) {
return format(calendar, new StringBuffer(mMaxLengthEstimate)).toString();
}
/* (non-Javadoc)
* @see org.apache.commons.lang3.time.DatePrinter#format(long, java.lang.StringBuffer)
*/
public StringBuffer format(final long millis, final StringBuffer buf) {
return format(new Date(millis), buf);
}
/* (non-Javadoc)
* @see org.apache.commons.lang3.time.DatePrinter#format(java.util.Date, java.lang.StringBuffer)
*/
public StringBuffer format(final Date date, final StringBuffer buf) {
final Calendar c = newCalendar(); // hard code GregorianCalendar
c.setTime(date);
return applyRules(c, buf);
}
/* (non-Javadoc)
* @see org.apache.commons.lang3.time.DatePrinter#format(java.util.Calendar, java.lang.StringBuffer)
*/
public StringBuffer format(final Calendar calendar, final StringBuffer buf) {
return applyRules(calendar, buf);
}
/**
* Performs the formatting by applying the rules to the specified calendar.
*
* @param calendar the calendar to format
* @param buf the buffer to format into
* @return the specified string buffer
*/
protected StringBuffer applyRules(final Calendar calendar, final StringBuffer buf) {
for (final Rule rule : mRules) {
rule.appendTo(buf, calendar);
}
return buf;
}
// Accessors
// -----------------------------------------------------------------------
/* (non-Javadoc)
* @see org.apache.commons.lang3.time.DatePrinter#getPattern()
*/
public String getPattern() {
return mPattern;
}
/* (non-Javadoc)
* @see org.apache.commons.lang3.time.DatePrinter#getTimeZone()
*/
public TimeZone getTimeZone() {
return mTimeZone;
}
/* (non-Javadoc)
* @see org.apache.commons.lang3.time.DatePrinter#getLocale()
*/
public Locale getLocale() {
return mLocale;
}
/**
* Gets an estimate for the maximum string length that the formatter will produce.
*
* <p>The actual formatted length will almost always be less than or equal to this amount.
*
* @return the maximum formatted length
*/
public int getMaxLengthEstimate() {
return mMaxLengthEstimate;
}
// Basics
// -----------------------------------------------------------------------
/**
* Compares two objects for equality.
*
* @param obj the object to compare to
* @return {@code true} if equal
*/
@Override
public boolean equals(final Object obj) {
if (obj instanceof FastDatePrinter == false) {
return false;
}
final FastDatePrinter other = (FastDatePrinter) obj;
return mPattern.equals(other.mPattern)
&& mTimeZone.equals(other.mTimeZone)
&& mLocale.equals(other.mLocale);
}
/**
* Returns a hashcode compatible with equals.
*
* @return a hashcode compatible with equals
*/
@Override
public int hashCode() {
return mPattern.hashCode() + 13 * (mTimeZone.hashCode() + 13 * mLocale.hashCode());
}
/**
* Gets a debugging string version of this formatter.
*
* @return a debugging string
*/
@Override
public String toString() {
return "FastDatePrinter[" + mPattern + "," + mLocale + "," + mTimeZone.getID() + "]";
}
// 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 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 StringBuffer buffer, final int value) {
buffer.append((char) (value / 10 + '0'));
buffer.append((char) (value % 10 + '0'));
}
// Rules
// -----------------------------------------------------------------------
/** Inner class defining a rule. */
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 buffer the output buffer
* @param calendar calendar to be appended
*/
void appendTo(StringBuffer buffer, Calendar calendar);
}
/** 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
*/
void appendTo(StringBuffer buffer, int value);
}
/** 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;
}
/** {@inheritDoc} */
public int estimateLength() {
return 1;
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
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} */
public int estimateLength() {
return mValue.length();
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
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} */
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} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
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 UnpaddedNumberField} with the specified field.
*
* @param field the field
*/
UnpaddedNumberField(final int field) {
mField = field;
}
/** {@inheritDoc} */
public int estimateLength() {
return 4;
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
appendTo(buffer, calendar.get(mField));
}
/** {@inheritDoc} */
public final void appendTo(final StringBuffer buffer, final int value) {
if (value < 10) {
buffer.append((char) (value + '0'));
} else if (value < 100) {
appendDigits(buffer, value);
} else {
buffer.append(value);
}
}
}
/** 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} */
public int estimateLength() {
return 2;
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
appendTo(buffer, calendar.get(Calendar.MONTH) + 1);
}
/** {@inheritDoc} */
public final void appendTo(final StringBuffer buffer, final int value) {
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} */
public int estimateLength() {
return mSize;
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
appendTo(buffer, calendar.get(mField));
}
/** {@inheritDoc} */
public final void appendTo(final StringBuffer buffer, int value) {
// pad the buffer with adequate zeros
for (int digit = 0; digit < mSize; ++digit) {
buffer.append('0');
}
// backfill the buffer with non-zero digits
int index = buffer.length();
for (; value > 0; value /= 10) {
buffer.setCharAt(--index, (char) ('0' + value % 10));
}
}
}
/** 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} */
public int estimateLength() {
return 2;
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
appendTo(buffer, calendar.get(mField));
}
/** {@inheritDoc} */
public final void appendTo(final StringBuffer buffer, final int value) {
if (value < 100) {
appendDigits(buffer, value);
} else {
buffer.append(value);
}
}
}
/** 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} */
public int estimateLength() {
return 2;
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
appendTo(buffer, calendar.get(Calendar.YEAR) % 100);
}
/** {@inheritDoc} */
public final void appendTo(final StringBuffer buffer, final int value) {
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} */
public int estimateLength() {
return 2;
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
appendTo(buffer, calendar.get(Calendar.MONTH) + 1);
}
/** {@inheritDoc} */
public final void appendTo(final StringBuffer buffer, final int value) {
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} */
public int estimateLength() {
return mRule.estimateLength();
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
int value = calendar.get(Calendar.HOUR);
if (value == 0) {
value = calendar.getLeastMaximum(Calendar.HOUR) + 1;
}
mRule.appendTo(buffer, value);
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final int value) {
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} */
public int estimateLength() {
return mRule.estimateLength();
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
int value = calendar.get(Calendar.HOUR_OF_DAY);
if (value == 0) {
value = calendar.getMaximum(Calendar.HOUR_OF_DAY) + 1;
}
mRule.appendTo(buffer, value);
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final int value) {
mRule.appendTo(buffer, value);
}
}
// -----------------------------------------------------------------------
private static final ConcurrentMap<TimeZoneDisplayKey, String> cTimeZoneDisplayCache =
new ConcurrentHashMap<TimeZoneDisplayKey, String>(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} */
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} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
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, false);
static final TimeZoneNumberRule INSTANCE_NO_COLON = new TimeZoneNumberRule(false, false);
static final TimeZoneNumberRule INSTANCE_ISO_8601 = new TimeZoneNumberRule(true, true);
final boolean mColon;
final boolean mISO8601;
/**
* Constructs an instance of {@code TimeZoneNumberRule} with the specified properties.
*
* @param colon add colon between HH and MM in the output if {@code true}
* @param iso8601 create an ISO 8601 format output
*/
TimeZoneNumberRule(final boolean colon, final boolean iso8601) {
mColon = colon;
mISO8601 = iso8601;
}
/** {@inheritDoc} */
public int estimateLength() {
return 5;
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
if (mISO8601 && calendar.getTimeZone().getID().equals("UTC")) {
buffer.append("Z");
return;
}
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(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} */
public int estimateLength() {
return length;
}
/** {@inheritDoc} */
public void appendTo(final StringBuffer buffer, final Calendar calendar) {
int zoneOffset = calendar.get(Calendar.ZONE_OFFSET);
if (zoneOffset == 0) {
buffer.append("Z");
return;
}
int offset = zoneOffset + 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 (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;
}
}
}