sascha@3011: package de.intevation.flys.utils;
sascha@3011: 
sascha@3011: import java.io.Serializable;
sascha@3011: 
sascha@3011: import java.util.Comparator;
sascha@3011: 
sascha@3011: public class EpsilonComparator
sascha@3011: implements   Serializable, Comparator<Double>
sascha@3011: {
sascha@3011:     public static final double EPSILON = 1e-5;
sascha@3011: 
sascha@3011:     public static final EpsilonComparator INSTANCE =
sascha@3011:         new EpsilonComparator(EPSILON);
sascha@3011: 
sascha@3011:     protected double epsilon;
sascha@3011: 
sascha@3011:     public EpsilonComparator() {
sascha@3011:         this(EPSILON);
sascha@3011:     }
sascha@3011: 
sascha@3011:     public EpsilonComparator(double epsilon) {
sascha@3011:         this.epsilon = Math.abs(epsilon);
sascha@3011:     }
sascha@3011: 
sascha@3011:     private static final double value(Double x) {
sascha@3011:         return x != null ? x.doubleValue() : 0.0;
sascha@3011:     }
sascha@3011: 
sascha@3011:     @Override
sascha@3011:     public int compare(Double a, Double b) {
sascha@3011:         double diff = value(a) - value(b);
sascha@3011:         if (diff < epsilon) return -1;
sascha@3011:         return diff > epsilon ? +1 : 0;
sascha@3011:     }
sascha@3011: }
sascha@3011: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :