net.sf.saxon.regex

Class UnicodeString

java.lang.Object

net.sf.saxon.regex.UnicodeString

Direct Known Subclasses:

BMPString, GeneralUnicodeString

public abstract class UnicodeString
extends Object

An abstract class that efficiently handles Unicode strings including non-BMP characters; it has two subclasses, one optimized for strings whose characters are all in the BMP, the other handling the general case.

Field Summary

Fields

Modifier and Type	Field and Description
static UnicodeString	EMPTY_STRING

Constructor Summary

Constructors

Constructor and Description
UnicodeString()

Method Summary

Methods

Modifier and Type	Method and Description
abstract int	charAt(int pos) Get the character at a specified position
static boolean	containsSurrogatePairs(CharSequence value) Test whether a CharSequence contains Unicode codepoints outside the BMP range
abstract CharSequence	getCharSequence() Get the value of this UnicodeString as a CharSequence
abstract int	indexOf(int search, int start) Get the first match for a given character
abstract boolean	isEnd(int pos) Ask whether a given position is at (or beyond) the end of the string
abstract int	length() Get the length of the string, in Unicode codepoints
static UnicodeString	makeUnicodeString(CharSequence in) Make a UnicodeString for a given CharSequence
static UnicodeString	makeUnicodeString(int[] in) Make a UnicodeString for a given array of codepoints
abstract UnicodeString	substring(int beginIndex, int endIndex) Get a substring of this string

Methods inherited from class java.lang.Object

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

Field Detail

EMPTY_STRING

public static UnicodeString EMPTY_STRING

Constructor Detail

UnicodeString

public UnicodeString()

Method Detail

makeUnicodeString

public static UnicodeString makeUnicodeString(CharSequence in)

Make a UnicodeString for a given CharSequence

Parameters:

in - the input CharSequence

Returns:

a UnicodeString using an appropriate implementation class

makeUnicodeString

public static UnicodeString makeUnicodeString(int[] in)

Make a UnicodeString for a given array of codepoints

Parameters:

in - the input CharSequence

Returns:

a UnicodeString using an appropriate implementation class

containsSurrogatePairs

public static boolean containsSurrogatePairs(CharSequence value)

Test whether a CharSequence contains Unicode codepoints outside the BMP range

Parameters:

value - the string to be tested

Returns:

true if the string contains non-BMP codepoints

substring

public abstract UnicodeString substring(int beginIndex,
                      int endIndex)

Get a substring of this string

Parameters:

beginIndex - the index of the first character to be included (counting codepoints, not 16-bit characters)

endIndex - the index of the first character to be NOT included (counting codepoints, not 16-bit characters)

Returns:

a substring

Throws:

IndexOutOfBoundsException - if the selection goes off the start or end of the string (this function follows the semantics of String.substring(), not the XPath semantics

indexOf

public abstract int indexOf(int search,
          int start)

Get the first match for a given character

Parameters:

search - the character to look for

start - the first position to look

Returns:

the position of the first occurrence of the sought character, or -1 if not found

charAt

public abstract int charAt(int pos)

Get the character at a specified position

Parameters:

pos - the index of the required character (counting codepoints, not 16-bit characters)

Returns:

a character (Unicode codepoint) at the specified position.

length

public abstract int length()

Get the length of the string, in Unicode codepoints

Returns:

the number of codepoints in the string

isEnd

public abstract boolean isEnd(int pos)

Ask whether a given position is at (or beyond) the end of the string

Parameters:

pos - the index of the required character (counting codepoints, not 16-bit characters)

Returns:

true iff if the specified index is after the end of the character stream

getCharSequence

public abstract CharSequence getCharSequence()

Get the value of this UnicodeString as a CharSequence

Returns:

a CharSequence representing the same characters as this UnicodeString