org.apache.commons.lang3.time

Class FastDateParser

java.lang.Object

org.apache.commons.lang3.time.FastDateParser

All Implemented Interfaces:

Serializable, DateParser

public class FastDateParser
extends Object
implements DateParser, Serializable

FastDateParser is a fast and thread-safe version of SimpleDateFormat.

To obtain a proxy to a FastDateParser, use FastDateFormat.getInstance(String, TimeZone, Locale) or another variation of the factory methods of FastDateFormat.

Since FastDateParser is thread safe, you can use a static member instance:

private static final DateParser DATE_PARSER = FastDateFormat.getInstance("yyyy-MM-dd");

This class can be used as a direct replacement for SimpleDateFormat in most parsing situations. This class is especially useful in multi-threaded server environments. SimpleDateFormat is not thread-safe in any JDK version, nor will it be as Sun has closed the bug/RFE.

Only parsing is supported by this class, but all patterns are compatible with SimpleDateFormat.

The class operates in lenient mode, so for example a time of 90 minutes is treated as 1 hour 30 minutes.

Timing tests indicate this class is as about as fast as SimpleDateFormat in single thread applications and about 25% faster in multi-thread applications.

Since:

3.2

See Also:

FastDatePrinter, Serialized Form

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	FastDateParser(String pattern, TimeZone timeZone, Locale locale) Constructs a new FastDateParser.
protected	FastDateParser(String pattern, TimeZone timeZone, Locale locale, Date centuryStart) Constructs a new FastDateParser.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj) Compare another object for equality with this object.
Locale	getLocale() Gets the locale used by this parser.
String	getPattern() Gets the pattern used by this parser.
TimeZone	getTimeZone() Gets the time zone used by this parser.
int	hashCode() Return a hash code compatible with equals.
Date	parse(String source) Equivalent to DateFormat.parse(String).
Date	parse(String source, ParsePosition pos) This implementation updates the ParsePosition if the parse succeeds.
boolean	parse(String source, ParsePosition pos, Calendar calendar) Parse a formatted date string according to the format.
Object	parseObject(String source) Parses text from a string to produce a Date.
Object	parseObject(String source, ParsePosition pos) Parses a date/time string according to the given parse position.
String	toString() Get a string version of this formatter.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

FastDateParser

protected FastDateParser(String pattern,
                         TimeZone timeZone,
                         Locale locale)

Constructs a new FastDateParser.

Use FastDateFormat.getInstance(String, TimeZone, Locale) or another variation of the factory methods of FastDateFormat to get a cached FastDateParser instance.

Parameters:

pattern - non-null SimpleDateFormat compatible pattern

timeZone - non-null time zone to use

locale - non-null locale

FastDateParser

protected FastDateParser(String pattern,
                         TimeZone timeZone,
                         Locale locale,
                         Date centuryStart)

Constructs a new FastDateParser.

Parameters:

pattern - non-null SimpleDateFormat compatible pattern

timeZone - non-null time zone to use

locale - non-null locale

centuryStart - The start of the century for 2 digit year parsing

Since:

3.5

Method Detail

getPattern

public String getPattern()

Description copied from interface: DateParser

Gets the pattern used by this parser.

Specified by:

getPattern in interface DateParser

Returns:

the pattern, SimpleDateFormat compatible

getTimeZone

public TimeZone getTimeZone()

Description copied from interface: DateParser

Gets the time zone used by this parser.

The default TimeZone used to create a Date when the TimeZone is not specified by the format pattern.

Specified by:

getTimeZone in interface DateParser

Returns:

the time zone

getLocale

public Locale getLocale()

Description copied from interface: DateParser

Gets the locale used by this parser.

Specified by:

getLocale in interface DateParser

Returns:

the locale

equals

public boolean equals(Object obj)

Compare another object for equality with this object.

Overrides:

equals in class Object

Parameters:

obj - the object to compare to

Returns:

trueif equal to this instance

hashCode

public int hashCode()

Return a hash code compatible with equals.

Overrides:

hashCode in class Object

Returns:

a hash code compatible with equals

toString

public String toString()

Get a string version of this formatter.

Overrides:

toString in class Object

Returns:

a debugging string

parseObject

public Object parseObject(String source)
                   throws ParseException

Description copied from interface: DateParser

Parses text from a string to produce a Date.

Specified by:

parseObject in interface DateParser

Parameters:

source - A String whose beginning should be parsed.

Returns:

a java.util.Date object

Throws:

ParseException - if the beginning of the specified string cannot be parsed.

See Also:

Format.parseObject(String)

parse

public Date parse(String source)
           throws ParseException

Description copied from interface: DateParser

Equivalent to DateFormat.parse(String). See DateFormat.parse(String) for more information.

Specified by:

parse in interface DateParser

Parameters:

source - A String whose beginning should be parsed.

Returns:

A Date parsed from the string

Throws:

ParseException - if the beginning of the specified string cannot be parsed.

parseObject

public Object parseObject(String source,
                          ParsePosition pos)

Description copied from interface: DateParser

Parses a date/time string according to the given parse position.

Specified by:

parseObject in interface DateParser

Parameters:

source - A String whose beginning should be parsed.

pos - the parse position

Returns:

a java.util.Date object

See Also:

DateFormat.parseObject(String, ParsePosition)

parse

public Date parse(String source,
                  ParsePosition pos)

This implementation updates the ParsePosition if the parse succeeds. However, it sets the error index to the position before the failed field unlike the method SimpleDateFormat.parse(String, ParsePosition) which sets the error index to after the failed field.

To determine if the parse has succeeded, the caller must check if the current parse position given by ParsePosition.getIndex() has been updated. If the input buffer has been fully parsed, then the index will point to just after the end of the input buffer.

Specified by:

parse in interface DateParser

Parameters:

source - A String, part of which should be parsed.

pos - A ParsePosition object with index and error index information as described above.

Returns:

A Date parsed from the string. In case of error, returns null.

See Also:

DateParser.parse(java.lang.String, java.text.ParsePosition)

parse

public boolean parse(String source,
                     ParsePosition pos,
                     Calendar calendar)

Parse a formatted date string according to the format. Updates the Calendar with parsed fields. Upon success, the ParsePosition index is updated to indicate how much of the source text was consumed. Not all source text needs to be consumed. Upon parse failure, ParsePosition error index is updated to the offset of the source text which does not match the supplied format.

Specified by:

parse in interface DateParser

Parameters:

source - The text to parse.

pos - On input, the position in the source to start parsing, on output, updated position.

calendar - The calendar into which to set parsed fields.

Returns:

true, if source has been parsed (pos parsePosition is updated); otherwise false (and pos errorIndex is updated)

Throws:

IllegalArgumentException - when Calendar has been set to be not lenient, and a parsed field is out of range.