What happens if you peek an empty stack Java?

What happens if you peek an empty stack Java?

Return Value: The method returns the element at the top of the Stack else returns NULL if the Stack is empty. Exception: The method throws EmptyStackException if the stack is empty.

Can you peek an empty stack?

Answer. At this particular stage of the Stack class implementation, calling peek() on an empty stack will result in a Python error message: AttributeError: ‘NoneType’ object has no attribute ‘get_value’ .

What is empty stack exception in Java?

public class EmptyStackException extends RuntimeException. Thrown by methods in the Stack class to indicate that the stack is empty. Since: JDK1.0 See Also: Stack , Serialized Form.

Can a stack be empty in Java?

Stack empty() Method in Java util. Stack. empty() method in Java is used to check whether a stack is empty or not. The method is of boolean type and returns true if the stack is empty else false.

What is a Linkedlist Java?

In Java, the linked list class is an ordered collection that contains many objects of the same type. Data in a Linked List is stored in a sequence of containers. The list holds a reference to the first container and each container has a link to the next one in the sequence.

What does peek () do in Java?

The peek() method of Queue Interface returns the element at the front the container. It does not deletes the element in the container. This method returns the head of the queue. The method does not throws an exception when the Queue is empty, it returns null instead.

What is peek () in stack?

In computer science, peek is an operation on certain abstract data types, specifically sequential collections such as stacks and queues, which returns the value of the top (“front”) of the collection without removing the element from the collection.

What is the type of exception thrown by peek method in Java?

Queue peek() method in Java This method returns the head of the queue. The method does not throws an exception when the Queue is empty, it returns null instead.

What is an empty stack?

stack::empty() function is an inbuilt function in C++ STL, which is defined in header file. empty() is used to check whether the associated container is empty or not and return true or false accordingly. The function checks the container should be empty means the size of the container should be 0.

How do you handle EmptyStackException in Java?

This example shows how to handle the empty stack exception by using s. empty(), s. pop() methods of Stack class and System. currentTimeMillis()method of Date class.

How do you empty a stack?

clear() method is used to remove all the elements from a Stack. Using the clear() method only clears all the element from the Stack and does not delete the Stack. In other words, we can say that the clear() method is used to only empty an existing Stack. Return Value: The function does not returns any value.

Is Empty method in Java?

Definition and Usage The isEmpty() method checks whether a string is empty or not. This method returns true if the string is empty (length() is 0), and false if not.