Complete Java SE 8 Developer Bootcamp - Collections

The video tutorial explains the Java ArrayList, a dynamic collection similar to arrays but resizable. It covers creating and using ArrayLists, adding and removing elements, and checking contents. The tutorial highlights the importance of overriding equals and hashCode methods for collections and discusses the collection interface's role in enabling polymorphism, making code flexible and interchangeable.

What is a key feature of an ArrayList that differentiates it from a regular array?

• It is dynamically resizable.

• It does not allow duplicate elements.

• It is statically sized.

• It can store only integers.

Which method is used to add elements to an ArrayList?

• insert()

• add()

• push()

• append()

What does the toString method do when called on an ArrayList?

• Removes all elements from the list.

• Converts the list to a string representation.

• Sorts the elements in the list.

• Adds a new element to the list.

Which method is used to determine the number of elements in an ArrayList?

• size()

• count()

• length()

• capacity()

How can you remove an element from an ArrayList?

• By using the erase() method.

• By using the discard() method.

• By using the remove() method.

• By using the delete() method.

Why is it important to override the equals method for objects stored in a collection?

• To prevent duplicate elements.

• To ensure objects are stored in alphabetical order.

• To allow the collection to compare objects correctly.

• To increase the speed of adding elements.

What concept allows collections to be easily replaced with one another?

• Encapsulation

• Inheritance

• Abstraction

• Polymorphism