Properties ArrayList (Class) and when ArrayList can be used .

ArrayList

1.  ArrayList is growable Array.
2.  ArrayList insertion order is preserved
3.  In ArrayList duplicates values are allowed
4.  In ArrayList null insertion is possible.
5.  In ArrayList we can insert Heterogeneous objects
6. During creation of object in ArrayList  it has default capacity 10.
     ArrayList obj=new ArrayList();  when ArrayList reaches default capacity it will increment based on this formula  
      new size=(current size*3/2)+1;
7. ArrayList implements Serializable,Clonable  and RandomAccess  interface.

ArrayList is best when accessing the elements frequently because ArrayList implements  RandomAccess  Interface. Because of RandomAccess we can access any elements at a same speed .