Package com.saxonica.expr.sort

Class UcaCollatorUsingIcu

java.lang.Object

com.saxonica.expr.sort.UcaCollatorUsingIcu

All Implemented Interfaces:

StringCollator, SubstringMatcher

public class UcaCollatorUsingIcu
extends java.lang.Object
implements SubstringMatcher

This class represents a collation (for comparing strings) implemented using the ICU library. It is available in Saxon-PE and Saxon-EE only.

Note that in the case that the ICU libraries have not been loaded, then this class is not instantiated. However, the public static functions, e.g. getLocales() could in theory be accessed via an XSLT stylesheet (such as the documentation generators for example) and these invoke ICU features The guard function com.saxonica.config.JavaPlatformPE.hasICUCollator() can be used to check.

Field Summary

Fields

Modifier and Type	Field	Description
int[]	maxIgnorable

Constructor Summary

Constructors

Constructor	Description
UcaCollatorUsingIcu(java.lang.String uri)	Construct a collation from a given UCA-based collation URI

Method Summary

Modifier and Type	Method	Description
boolean	comparesEqual(UnicodeString s1, UnicodeString s2)	Compare two strings for equality.
int	compareStrings(UnicodeString o1, UnicodeString o2)	Compare two strings
boolean	contains(UnicodeString s1, UnicodeString s2)	Test whether one string contains another, according to the rules of the XPath contains() function
boolean	endsWith(UnicodeString s1, UnicodeString s2)	Test whether one string ends with another, according to the rules of the XPath ends-with() function
java.text.CollationKey	getCollationKey(java.lang.String source)	Factory method to generate a collation key for a given string, using this collation
AtomicMatchKey	getCollationKey(UnicodeString s)	Get a collation key for a String.
java.lang.String	getCollationURI()	Get the collation URI.
static java.lang.String[]	getLocales()	Return the locales supported in this version of ICU Note that with Java 6 this method has been known to throw an array index exception from RuleBasedCollator, With Java 7 this performs correctly and getAvailableLocales() does not appear to be invoked from any of the UCA or numbering support.
com.ibm.icu.text.RuleBasedCollator	getRuleBasedCollator()	Get the underlying ICU collator represented by this collation object
int	getStrength()
static java.lang.String	getUCAVersion()	Return the version of UCA supported
int	hashCode()	Get a hash code for the purpose of comparing whether this is the same collation as another.
void	setProps(java.util.Properties props)	Set the properties for the UCA collation
void	setStrength(int newStrength)
java.lang.String	show()	Display details of this collation
boolean	startsWith(UnicodeString s1, UnicodeString s2)	Test whether one string starts with another, according to the rules of the XPath starts-with() function
UnicodeString	substringAfter(UnicodeString s1, UnicodeString s2)	Return the part of a string after a given substring, according to the rules of the XPath substring-after() function
UnicodeString	substringBefore(UnicodeString s1, UnicodeString s2)	Return the part of a string before a given substring, according to the rules of the XPath substring-before() function

Methods inherited from class java.lang.Object

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

Field Detail

maxIgnorable

public int[] maxIgnorable

Constructor Detail

UcaCollatorUsingIcu

public UcaCollatorUsingIcu(java.lang.String uri)
                    throws XPathException

Construct a collation from a given UCA-based collation URI

Parameters:

uri - the collation URI, conforming to the syntax defined in the W3C Functions and Operators specification.

Throws:

XPathException - if the URI is invalid

Method Detail

getUCAVersion

public static java.lang.String getUCAVersion()

Return the version of UCA supported

Returns:

UCA version as nn.nn.nn.nn

getRuleBasedCollator

public com.ibm.icu.text.RuleBasedCollator getRuleBasedCollator()

Get the underlying ICU collator represented by this collation object

Returns:

the underlying ICU collator

getLocales

public static java.lang.String[] getLocales()

Return the locales supported in this version of ICU Note that with Java 6 this method has been known to throw an array index exception from RuleBasedCollator, With Java 7 this performs correctly and getAvailableLocales() does not appear to be invoked from any of the UCA or numbering support.

Returns:

The language tags and display names separated by semicolon

show

public java.lang.String show()

Display details of this collation

Returns:

a string suitable for diagnostic display

getCollationKey

public java.text.CollationKey getCollationKey(java.lang.String source)

Factory method to generate a collation key for a given string, using this collation

Parameters:

source - the supplied string

Returns:

a collation key with the property that two strings that are deemed equal under this collation generate the same collation key (according to the Object.equals(Object) and CollationKey.compareTo(CollationKey) methods).

hashCode

public int hashCode()

Get a hash code for the purpose of comparing whether this is the same collation as another.

Overrides:

hashCode in class java.lang.Object

Returns:

a suitable hash code

setProps

public void setProps(java.util.Properties props)
              throws XPathException

Set the properties for the UCA collation

Parameters:

props - the set of properties parsed from the UCA parameters

Throws:

XPathException - if the properties are invalid

setStrength

public void setStrength(int newStrength)

getStrength

public int getStrength()

comparesEqual

public boolean comparesEqual(UnicodeString s1,
                             UnicodeString s2)

Description copied from interface: StringCollator

Compare two strings for equality. This may be more efficient than using compareStrings and testing whether the result is zero, but it must give the same result

Specified by:

comparesEqual in interface StringCollator

Parameters:

s1 - the first string

s2 - the second string

Returns:

true if and only if the strings are considered equal,

getCollationURI

public java.lang.String getCollationURI()

Description copied from interface: StringCollator

Get the collation URI. It must be possible to use this collation URI to reconstitute the collation

Specified by:

getCollationURI in interface StringCollator

Returns:

a collation URI that can be used to reconstruct the collation when an XSLT package is reloaded.

compareStrings

public int compareStrings(UnicodeString o1,
                          UnicodeString o2)

Description copied from interface: StringCollator

Compare two strings

Specified by:

compareStrings in interface StringCollator

Parameters:

o1 - the first string

o2 - the second string

Returns:

0 if the strings are considered equal, a negative integer if the first string is less than the second, a positive integer if the first string is greater than the second

getCollationKey

public AtomicMatchKey getCollationKey(UnicodeString s)

Description copied from interface: StringCollator

Get a collation key for a String. The essential property of collation keys is that if (and only if) two strings are equal under the collation, then comparing the collation keys using the equals() method must return true.

Specified by:

getCollationKey in interface StringCollator

Parameters:

s - the string whose collation key is required

Returns:

the collation key

contains

public boolean contains(UnicodeString s1,
                        UnicodeString s2)

Test whether one string contains another, according to the rules of the XPath contains() function

Specified by:

contains in interface SubstringMatcher

Parameters:

s1 - the containing string

s2 - the contained string

Returns:

true iff s1 contains s2

endsWith

public boolean endsWith(UnicodeString s1,
                        UnicodeString s2)

Test whether one string ends with another, according to the rules of the XPath ends-with() function

Specified by:

endsWith in interface SubstringMatcher

Parameters:

s1 - the containing string

s2 - the contained string

Returns:

true iff s1 ends with s2

startsWith

public boolean startsWith(UnicodeString s1,
                          UnicodeString s2)

Test whether one string starts with another, according to the rules of the XPath starts-with() function

Specified by:

startsWith in interface SubstringMatcher

Parameters:

s1 - the containing string

s2 - the contained string

Returns:

true iff s1 starts with s2

substringAfter

public UnicodeString substringAfter(UnicodeString s1,
                                    UnicodeString s2)

Return the part of a string after a given substring, according to the rules of the XPath substring-after() function

Specified by:

substringAfter in interface SubstringMatcher

Parameters:

s1 - the containing string

s2 - the contained string

Returns:

the part of s1 that follows the first occurrence of s2

substringBefore

public UnicodeString substringBefore(UnicodeString s1,
                                     UnicodeString s2)

Return the part of a string before a given substring, according to the rules of the XPath substring-before() function

Specified by:

substringBefore in interface SubstringMatcher

Parameters:

s1 - the containing string

s2 - the contained string

Returns:

the part of s1 that precedes the first occurrence of s2