ARRAYLIST in java

ArrayList implements all List operations using List interface and is also accept null values.The ArrayList is re sizable i.e shrinks and grows automatically and it has a capacity .

The class hierarchy is as follow:
---->Java.Lang.Object
      ----->Java.Util.AbstactCollection
                ----->Java.Util.AbstractList
                        ------>Java.Util.ArrayList

The array list contains following methods for implementing different operations

Return type	Method name
void	add (int index, Object o)
boolean	add (Object o)
boolean	addAll (Collection c)
boolean	addAll (int index,Collection c)
void	clear ( )
Object	clone ( )
boolean	contains (Object o )
Object	get (int index)
int	indexOf(Object o)
boolean	isEmpty( )
int	lastIndexOf( Object o)
Object	remove( int index)
Protected void	removeRange( int fromIndex, int toIndex)
Object	set (int index, Object o)
int	size ( )
Object [ ]	toArray( )
Object [ ]	toArray (Object [ ] a)
void	trimToSize( )

The program bellow consists of above methods in a nutshell

package Object;

import java.util.ArrayList;
import java.util.ListIterator;

public class ArrayList1 {

 /**
  * @param args
  */
 public static void main(String[] args) {
  // TODO Auto-generated method stub
ArrayList<String> myList = new ArrayList<String>();
ArrayList<String>myList1 = new ArrayList<String>();
// adding elements
myList.add("a"); // add by object
myList.add("b");
myList.add("c");
myList.add("d");
myList.add("e");
myList.add("f");
myList.add("g");
myList.add(7, "k"); // add by index 
myList1.addAll(myList ); // adding all elements of myList to myList1

System.out.println(myList);
System.out.println(myList1);

// inserting a element at index 2
myList.add(2, "element");
System.out.println(myList);

// set the in particular index
myList.set(0, "new set"); // setting "new set" at index 0 

// checking the size
for (int i=0;i<myList.size();i++)
{
System.out.println("the element of index "+" " + i + " "+"is " + myList.get(i));
}
//remove by index
myList.remove(5);
System.out.println(myList); // e will be removed

//remove by object value

myList.remove("g");
System.out.println(myList); // g will be removed

//clone the array list
ArrayList<String>Testlist = (ArrayList<String>)myList.clone();
//shallow copy of this ArrayList instance prints 
//[a, b, element, c, d, f, k]
System.out.println("the clone is " + Testlist);     

// contains
System.out.println(myList.contains("a")); // returns false
System.out.println(myList.contains(Testlist)); // return false

// is empty
System.out.println(myList.isEmpty());

// lastIndexOf
System.out.println(myList.lastIndexOf("k")); // prints 6
System.out.println(myList.lastIndexOf("g")); //prints -1 because missing in list

//toArray
String [] myString = Testlist.toArray(new String[Testlist.size()]);

System.out.println(myString.toString()); //[Ljava.lang.String;@10385c1
System.out.println(Testlist.size());

//TrimToSize
Testlist.trimToSize();
System.out.println(Testlist);

//retainAll
System.out.println(myList1);
System.out.println(myList);
//retains all the elements which are common in in myList1 and myList
boolean b =myList1.retainAll(myList);
System.out.println(b);
System.out.println(myList1);

//ListIterator
System.out.println(myList1);
ListIterator<String> it = myList1.listIterator();
while(it.hasNext())
System.out.println(it.next()); // prints one by one elements in myList1
//remove, remove all
Testlist.remove(1);
System.out.println(Testlist); // b is removed

Testlist.removeAll(Testlist);
System.out.println(Testlist); // removes all element in Testlist, prints []

// clear the list
myList.clear();
System.out.println(myList); // prints []

}

}

//output are as follow:--

========================

[a, b, c, d, e, f, g, k]
[a, b, c, d, e, f, g, k]
[a, b, element, c, d, e, f, g, k]
the element of index  0 is new set
the element of index  1 is b
the element of index  2 is element
the element of index  3 is c
the element of index  4 is d
the element of index  5 is e
the element of index  6 is f
the element of index  7 is g
the element of index  8 is k
[new set, b, element, c, d, f, g, k]
[new set, b, element, c, d, f, k]
the clone is [new set, b, element, c, d, f, k]
false
false
false
6
-1
[Ljava.lang.String;@30c221
7
[new set, b, element, c, d, f, k]
[a, b, c, d, e, f, g, k]
[new set, b, element, c, d, f, k]
true
[b, c, d, f, k]
[b, c, d, f, k]
b
c
d
f
k
[new set, element, c, d, f, k]
[]
[]