Here you can find the source of Abs(Object in)
public static final void Abs(Object in)
//package com.java2s; //License from project: Open Source License public class Main { public static final void Abs(Object in) { if (in == null) return; if (in instanceof double[]) { double[] inn = (double[]) in; for (int i = 0, s = inn.length; i < s; i++) { double x = inn[i]; inn[i] = (x > 0 ? x : -x); }//from w w w . j a v a 2 s. c o m } else { for (int i = 0, s = ((Object[]) in).length; i < s; i++) Abs(((Object[]) in)[i]); } } }