Module com.github.f4b6a3.uuid

Package com.github.f4b6a3.uuid.codec

Class StringCodec

java.lang.Object

com.github.f4b6a3.uuid.codec.StringCodec

All Implemented Interfaces:

UuidCodec<String>

public class StringCodec
extends Object
implements UuidCodec<String>

Codec for UUID string representation as defined in RFC-4122.

The string representation, also referred as canonical textual representation, is a string of 32 hexadecimal (base-16) digits, displayed in five groups separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters (32 hexadecimal characters and 4 hyphens).

This codec decodes (parses) strings in these formats, with/without hyphens:

• 00000000-0000-V000-0000-000000000000 (canonical string)
• {00000000-0000-V000-0000-000000000000} (MS GUID string)
• urn:uuid:00000000-0000-V000-0000-000000000000 (URN UUID string)

The encoding and decoding processes can be much faster (7x) than UUID.toString() and UUID.fromString(String) in JDK 8.

If you prefer a string representation without hyphens, use Base16Codec instead of StringCodec. Base16Codec can be much faster (22x) than doing uuid.toString().replaceAll("-", "").

Field Summary

Fields

Modifier and Type	Field	Description
static StringCodec	INSTANCE	A shared immutable instance.

Constructor Summary

Constructors

Constructor	Description
StringCodec()

Method Summary

Modifier and Type	Method	Description
UUID	decode(String string)	Get a UUID from a string.
String	encode(UUID uuid)	Get a string from a UUID.
protected static int	getJavaVersion()	Returns the java major version number.
protected static char[]	toCharArray(String string)	Returns a char array of a string.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

INSTANCE

public static final StringCodec INSTANCE

A shared immutable instance.

Constructor Detail

StringCodec

public StringCodec()

Method Detail

encode

public String encode(UUID uuid)

Get a string from a UUID.

It can be much faster than UUID.toString() in JDK 8.

Specified by:

encode in interface UuidCodec<String>

Parameters:

uuid - a UUID

Returns:

a UUID string

Throws:

InvalidUuidException - if the argument is invalid

decode

public UUID decode(String string)

Get a UUID from a string.

It accepts strings:

• With URN prefix: "urn:uuid:";
• With curly braces: '{' and '}';
• With upper or lower case;
• With or without hyphens.

It can be much faster than UUID.fromString(String) in JDK 8.

It also can be twice as fast as UUID.fromString(String) in JDK 11.

Specified by:

decode in interface UuidCodec<String>

Parameters:

string - a UUID string

Returns:

a UUID

Throws:

InvalidUuidException - if the argument is invalid

toCharArray

protected static char[] toCharArray(String string)

Returns a char array of a string.

It removes URN prefix and curly braces from the string.

Parameters:

string - a string

Returns:

a substring

getJavaVersion

protected static int getJavaVersion()

Returns the java major version number.

Returns:

major version number

See Also:

JDK Releases