Java Integer Caching and Autoboxing

BoxingTest.java

package boxingtest;

import java.util.Scanner;

public class BoxingTest
{
  public static void main(String[] args)
  {
    Integer[] ints = new Integer[100000];
    for (int i = 0; i < ints.length; i++)
    {
      // Integer initializ              // Test -   count     size for java.lang.Integer
      // ints[i] = new Integer(i);      // T1   -  100003  1600048 // Always creates new instance
      // ints[i] = new Integer(1);      // T2   -  100003  1600048 // Always creates new instance
      // ints[i] = Integer.valueOf(i);  // T3   -  100131  1602096 // Triggers Integer cache
      // ints[i] = Integer.valueOf(1);  // T4   -     259     4144 // Triggers Integer cache
      // ints[i] = i;                   // T5   -  100131  1602096 // Triggers Integer cache via valueOf()
      // ints[i] = 1;                   // T6   -     259     4144 // Triggers Integer cache via valueOf()
    }
    System.out.println("Run 'jmap -histo:live <jpid>' and press Enter...");
    new Scanner(System.in).nextLine();
    // Keep a ref to ints to prevent them from being GCed during jmap.
    System.out.format("Allocated %d Integers.%n", ints.length);

    /**
     * NOTE: Use -Djava.lang.Integer.IntegerCache.high=N to alter the Integer cache range.
     *       Default highest value is 127.
     */
  }
}