Get Object[] length in ArrayList

Question

How do I get the size of the Object[] in ArrayList?
Not ArrayList.size() which returns how many Elements
are in the List.

Answer 1

You could use reflection if you really wanted to know
how much memory you have "wasted".
KajHere's a stupid class to do just that.
Thanks.
import java.util.*;
import java.lang.reflect.*;
public class Test{
public static void main(String[] args){
     new Test();
public Test(){
     List list = new ArrayList(1);
     double capacity = 0;
     double size = 0;
     Random rand = new Random();
     int iter = rand.nextInt(100);
     System.out.println("Iter: " + iter);
     for(int i = 0; i < iter; i++){
     int rn = rand.nextInt(10);
     Integer integer = new Integer(rn);
     list.add(integer);
     size = list.size();
     System.out.println("List Size: " + size);
     try{
     Class al = list.getClass();
     // Get Declared Fields
     System.out.println("\nGet Declared Fields");
     Field[] fields1 = al.getDeclaredFields();
     for(int i = 0; i < fields1.length; i++){
     System.out.println("Field: " + fields1.getName());
     // Get Fields
     System.out.println("\nGet Fields");
     Field[] fields2 = al.getFields();
     for(int i = 0; i < fields2.length; i++){
     System.out.println("Field: " + fields2[i].getName());
     // Get Field
     System.out.println("\nGet Field");
     //Field field = al.getField("elementData");
     Field field = fields1[1];
     field.setAccessible(true);
     System.out.println("Field (elementData): " + field.getName());
     Object obj = field.get(list);
     Object[] elementData = (Object[])obj;
     capacity = elementData.length;
     } catch(Exception e){
     e.printStackTrace();
System.out.println("List Capacity: " + capacity);
     int percentOver = (int)(((capacity - size) / capacity) * 100);
System.out.println("Percent Over: " + percentOver);