Java.util.Stack Class


The java.util.Stack class represents a last-in-first-out (LIFO) stack of objects.

  • When a stack is first created, it contains no items.

  • In this class, the last element inserted is accessed first.

Class declaration

Following is the declaration for java.util.Stack class −

public class Stack<E>
   extends Vector<E>

Class constructors

Sr.No. Constructor & Description


This constructor creates an empty stack.

Class methods

Sr.No. Method & Description
1 boolean empty()

This method tests if this stack is empty.

2 E peek()

This method looks at the object at the top of this stack without removing it from the stack.

3 E pop()

This method removes the object at the top of this stack and returns that object as the value of this function.

4 E push(E item)

This method pushes an item onto the top of this stack.

5 int search(Object o)

This method returns the 1-based position where an object is on this stack.

Methods inherited

This class inherits methods from the following classes −

  • java.util.Vector
  • java.util.AbstractList
  • java.util.Object
  • java.util.List