Get the size and trim to size

To reduce the size of the array, call trimToSize( )

int size()
Returns the number of elements in this list.
void trimToSize()
Trims the capacity of this ArrayList instance to be the list's current size.

import java.util.ArrayList;

public class Main {
  public static void main(String args[]) {
    ArrayList<String> al = new ArrayList<String>();

    al.add("C");
    al.add("java2s.com");
    al.add("D");
    al.add("F");
    al.add(1, "java2s.com");

    al.trimToSize();

    System.out.println(al.size());
  }

}

The output: 


5
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ArrayList:
  1. ArrayList Class
  2. Create ArrayList object
  3. Add to ArrayList
  4. Clear an ArrayList
  5. Shallow copy of current ArrayList
  6. If contain a certain object
  7. Increases the capacity of an ArrayList
  8. Get/Replace element by index
  9. Get object for index
  10. Remove from ArrayList
  11. Get the size and trim to size
  12. If ArrayList is empty
  13. Convert ArrayList to array