Class EmptyGreatestComparer

java.lang.Object

net.sf.saxon.sort.EmptyGreatestComparer

All Implemented Interfaces:

Serializable, Comparator

public class EmptyGreatestComparer
extends Object
implements Comparator, Serializable

A Comparer that modifies a base comparer by sorting empty key values and NaN values last (greatest), as opposed to the default which sorts them first.

Author:

Michael H. Kay

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
EmptyGreatestComparer(AtomicComparer baseComparer)

Method Summary

Modifier and Type	Method	Description
int	compare(Object a, Object b)	Compare two AtomicValue objects according to the rules for their data type.

Methods inherited from class Object

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

Methods inherited from interface Comparator

equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Constructor Details

EmptyGreatestComparer

public EmptyGreatestComparer(AtomicComparer baseComparer)

Method Details

compare

public int compare(Object a,
 Object 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:

compare in interface Comparator

Parameters:

a - the first object to be compared. It is intended that this should normally be an instance of AtomicValue, though this restriction is not enforced. If it is a StringValue, the collator is used to compare the values, otherwise the value must implement the java.util.Comparable interface.

b - the second object to be compared. This must be comparable with the first object: for example, if one is a string, they must both be strings.

Returns:

invalid input: '<'0 if ainvalid input: '<'b, 0 if a=b, >0 if a>b

Throws:

ClassCastException - if the objects are not comparable