Class NumericComparer

  • All Implemented Interfaces:
    java.io.Serializable, java.util.Comparator

    public class NumericComparer
    extends java.lang.Object
    implements java.util.Comparator, java.io.Serializable
    A Comparer used for comparing sort keys when data-type="number". The items to be compared are converted to numbers, and the numbers are then compared directly.

    This class is used in XSLT only, so there is no need to handle XQuery's "empty least" vs "empty greatest" options.

    Author:
    Michael H. Kay
    See Also:
    Serialized Form
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int compare​(java.lang.Object a, java.lang.Object b)
      Compare two Items by converting them to numbers and comparing the numeric values.
      static NumericComparer getInstance()  
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
      • Methods inherited from interface java.util.Comparator

        equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong
    • Method Detail

      • compare

        public int compare​(java.lang.Object a,
                           java.lang.Object b)
        Compare two Items by converting them to numbers and comparing the numeric values. If either value cannot be converted to a number, it is treated as NaN, and compares less that the other (two NaN values compare equal).
        Specified by:
        compare in interface java.util.Comparator
        Parameters:
        a - the first Item to be compared.
        b - the second Item to be compared.
        Returns:
        <0 if a0 if a>b
        Throws:
        java.lang.ClassCastException - if the objects are not Items