Explain about Stack with an example

Stack is a child class of Vector. Stack is Last In First Out (LIFO).

Heterogeneous Objects are allowed.

Insertion order is preserved.

Duplicate Objects are allowed.

Null insertion is possible.

Constructor:

Stack s=new Stack();

Methods in Stack:

push() – To insert object into stack

pop() – To remove object

peek() – To return object without remove

boolean empty() – Return true if the stack is empty

int search() – Return offset, if the element is available otherwise return-1

import java.util.*;

public class StackDemo {

               public static void main(String[] arg) {                  

                               Stack s=new Stack();

                               s.push("a");

                               s.push("b");

                               s.push(null);//null insertion allowed

                               s.push("c");

                               s.push("a");//duplicates are allowed        

                               System.out.println(s); // [a, b, null, c, a]

                               s.pop();

                               System.out.println(s); //[a, b, null, c]

                               System.out.println(s.search("c")); // 1 (offset is 1)                            

               }

}