/// <summary>
/// Returns a name in the specified {@code style} of this {@code TimeZone}
/// suitable for presentation to the user in the specified {@code
/// locale}. If the specified {@code daylight} is {@code true}, a Daylight
/// Saving Time name is returned (even if this {@code TimeZone} doesn't
/// observe Daylight Saving Time). Otherwise, a Standard Time name is
/// returned.
///
/// <para>When looking up a time zone name, the {@linkplain
/// ResourceBundle.Control#getCandidateLocales(String,Locale) default
/// <code>Locale</code> search path of <code>ResourceBundle</code>} derived
/// from the specified {@code locale} is used. (No {@linkplain
/// ResourceBundle.Control#getFallbackLocale(String,Locale) fallback
/// <code>Locale</code>} search is performed.) If a time zone name in any
/// {@code Locale} of the search path, including <seealso cref="Locale#ROOT"/>, is
/// found, the name is returned. Otherwise, a string in the
/// <a href="#NormalizedCustomID">normalized custom ID format</a> is returned.
///
/// </para>
/// </summary>
/// <param name="daylight"> {@code true} specifying a Daylight Saving Time name, or
/// {@code false} specifying a Standard Time name </param>
/// <param name="style"> either <seealso cref="#LONG"/> or <seealso cref="#SHORT"/> </param>
/// <param name="locale"> the locale in which to supply the display name. </param>
/// <returns> the human-readable name of this time zone in the given locale. </returns>
/// <exception cref="IllegalArgumentException"> if {@code style} is invalid. </exception>
/// <exception cref="NullPointerException"> if {@code locale} is {@code null}.
/// @since 1.2 </exception>
/// <seealso cref= java.text.DateFormatSymbols#getZoneStrings() </seealso>
public virtual String GetDisplayName(bool daylight, int style, Locale locale)
{
if (style != SHORT && style != LONG)
{
throw new IllegalArgumentException("Illegal style: " + style);
}
String id = ID;
String name = TimeZoneNameUtility.retrieveDisplayName(id, daylight, style, locale);
if (name != null)
{
return(name);
}
if (id.StartsWith("GMT") && id.Length() > 3)
{
char sign = id.CharAt(3);
if (sign == '+' || sign == '-')
{
return(id);
}
}
int offset = RawOffset;
if (daylight)
{
offset += DSTSavings;
}
return(ZoneInfoFile.toCustomID(offset));
}
/// <summary>
/// Converts this {@code TimeZone} object to a {@code ZoneId}.
/// </summary>
/// <returns> a {@code ZoneId} representing the same time zone as this
/// {@code TimeZone}
/// @since 1.8 </returns>
public virtual ZoneId ToZoneId()
{
String id = ID;
if (ZoneInfoFile.useOldMapping() && id.Length() == 3)
{
if ("EST".Equals(id))
{
return(ZoneId.Of("America/New_York"));
}
if ("MST".Equals(id))
{
return(ZoneId.Of("America/Denver"));
}
if ("HST".Equals(id))
{
return(ZoneId.Of("America/Honolulu"));
}
}
return(ZoneId.Of(id, ZoneId.SHORT_IDS));
}
/// <summary>
/// Parses a custom time zone identifier and returns a corresponding zone.
/// This method doesn't support the RFC 822 time zone format. (e.g., +hhmm)
/// </summary>
/// <param name="id"> a string of the <a href="#CustomID">custom ID form</a>. </param>
/// <returns> a newly created TimeZone with the given offset and
/// no daylight saving time, or null if the id cannot be parsed. </returns>
private static TimeZone ParseCustomTimeZone(String id)
{
int length;
// Error if the length of id isn't long enough or id doesn't
// start with "GMT".
if ((length = id.Length()) < (GMT_ID_LENGTH + 2) || id.IndexOf(GMT_ID) != 0)
{
return(null);
}
ZoneInfo zi;
// First, we try to find it in the cache with the given
// id. Even the id is not normalized, the returned ZoneInfo
// should have its normalized id.
zi = ZoneInfoFile.getZoneInfo(id);
if (zi != null)
{
return(zi);
}
int index = GMT_ID_LENGTH;
bool negative = false;
char c = id.CharAt(index++);
if (c == '-')
{
negative = true;
}
else if (c != '+')
{
return(null);
}
int hours = 0;
int num = 0;
int countDelim = 0;
int len = 0;
while (index < length)
{
c = id.CharAt(index++);
if (c == ':')
{
if (countDelim > 0)
{
return(null);
}
if (len > 2)
{
return(null);
}
hours = num;
countDelim++;
num = 0;
len = 0;
continue;
}
if (c < '0' || c > '9')
{
return(null);
}
num = num * 10 + (c - '0');
len++;
}
if (index != length)
{
return(null);
}
if (countDelim == 0)
{
if (len <= 2)
{
hours = num;
num = 0;
}
else
{
hours = num / 100;
num %= 100;
}
}
else
{
if (len != 2)
{
return(null);
}
}
if (hours > 23 || num > 59)
{
return(null);
}
int gmtOffset = (hours * 60 + num) * 60 * 1000;
if (gmtOffset == 0)
{
zi = ZoneInfoFile.getZoneInfo(GMT_ID);
if (negative)
{
zi.ID = "GMT-00:00";
}
else
{
zi.ID = "GMT+00:00";
}
}
else
{
zi = ZoneInfoFile.getCustomTimeZone(id, negative ? -gmtOffset : gmtOffset);
}
return(zi);
}
