Here you can find the source of sizeOf(int[] arr)
public static int sizeOf(int[] arr)
//package com.java2s; //License from project: Open Source License public class Main { public static int sizeOf(int[] arr) { return arr == null ? 0 : arr.length; }//from w ww. j a va2s .co m public static int sizeOf(char[] arr) { return arr == null ? 0 : arr.length; } public static int sizeOf(byte[] arr) { return arr == null ? 0 : arr.length; } public static int sizeOf(Object[] arr) { return arr == null ? 0 : arr.length; } public static int sizeOf(String[] arr) { return arr == null ? 0 : arr.length; } }