Package net.sf.saxon.expr.sort

Class DecimalSortComparer

java.lang.Object

net.sf.saxon.expr.sort.DecimalSortComparer

All Implemented Interfaces:

AtomicComparer

public class DecimalSortComparer
extends java.lang.Object
implements AtomicComparer

An AtomicComparer used for sorting values that are known to be instances of xs:decimal (including xs:integer), It also supports a separate method for getting a collation key to test equality of items

Method Summary

Modifier and Type	Method	Description
int	compareAtomicValues(AtomicValue a, AtomicValue b)	Compare two AtomicValue objects according to the rules for their data type.
boolean	comparesEqual(AtomicValue a, AtomicValue b)	Compare two AtomicValue objects for equality according to the rules for their data type.
StringCollator	getCollator()	Get the collation used by this AtomicComparer if any
static DecimalSortComparer	getDecimalSortComparerInstance()
AtomicComparer	provideContext(XPathContext context)	Supply the dynamic context in case this is needed for the comparison
java.lang.String	save()	Create a string representation of this AtomicComparer that can be saved in a compiled package and used to reconstitute the AtomicComparer when the package is reloaded

Methods inherited from class java.lang.Object

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

Method Detail

getDecimalSortComparerInstance

public static DecimalSortComparer getDecimalSortComparerInstance()

getCollator

public StringCollator getCollator()

Description copied from interface: AtomicComparer

Get the collation used by this AtomicComparer if any

Specified by:

getCollator in interface AtomicComparer

Returns:

the collation used for comparing strings, or null if not applicable

provideContext

public AtomicComparer provideContext(XPathContext context)

Supply the dynamic context in case this is needed for the comparison

Specified by:

provideContext in interface AtomicComparer

Parameters:

context - the dynamic evaluation context

Returns:

either the original AtomicComparer, or a new AtomicComparer in which the context is known. The original AtomicComparer is not modified

compareAtomicValues

public int compareAtomicValues(AtomicValue a,
                               AtomicValue b)

Compare two AtomicValue objects according to the rules for their data type. UntypedAtomic values are compared as if they were strings; if different semantics are wanted, the conversion must be done by the caller.

Specified by:

compareAtomicValues in interface AtomicComparer

Parameters:

a - the first object to be compared. This must be an AtomicValue and it must implement Comparable with context-free XPath comparison semantics

b - the second object to be compared. This must be an AtomicValue and it must implement Comparable with context-free XPath comparison semantics

Returns:

<0 if a<b, 0 if a=b, >0 if a>b

Throws:

java.lang.ClassCastException - if the objects are not comparable

comparesEqual

public boolean comparesEqual(AtomicValue a,
                             AtomicValue b)

Compare two AtomicValue objects for equality according to the rules for their data type. UntypedAtomic values are compared by converting to the type of the other operand.

Specified by:

comparesEqual in interface AtomicComparer

Parameters:

a - the first object to be compared. This must be an AtomicValue and it must implement equals() with context-free XPath comparison semantics

b - the second object to be compared. This must be an AtomicValue and it must implement equals() with context-free XPath comparison semantics

Returns:

true if the values are equal, false if not

Throws:

java.lang.ClassCastException - if the objects are not comparable

save

public java.lang.String save()

Create a string representation of this AtomicComparer that can be saved in a compiled package and used to reconstitute the AtomicComparer when the package is reloaded

Specified by:

save in interface AtomicComparer

Returns:

a string representation of the AtomicComparer