Learn Java from Scratch - A Beginner's Guide - Step 05 - Understanding String Is Immutable and String Concat, Upper Case

The video tutorial explains the concept of string immutability, demonstrating how strings in programming cannot be changed once created. It shows how concatenation creates new strings rather than modifying existing ones. The tutorial also covers various string methods like converting to uppercase, lowercase, and trimming spaces. The video concludes with a summary and a preview of upcoming topics.

What does it mean when we say a string is immutable?

• The string can be changed only in certain conditions.

• The string cannot be changed once created.

• The string can be changed directly.

• The string can be changed by using a special method.

What happens when you use the concat method on a string?

• The original string is deleted.

• A new string is created with the concatenated value.

• The original string is modified.

• The original string is reversed.

After concatenating a string with another, what remains unchanged?

• The length of the original string

• Both strings

• The new string

• The original string

What is the result of executing a method on an immutable string?

• The original string is modified.

• The original string is deleted.

• The method fails to execute.

• A new string is created with the result.

Which method would you use to convert a string to all uppercase letters?

• concat()

• trim()

• toLowerCase()

• toUpperCase()

How can you remove spaces from the start and end of a string?

• Using the concat method

• Using the trim method

• Using the toUpperCase method

• Using the toLowerCase method

What is the purpose of the trim method in string manipulation?

• To add spaces to a string

• To concatenate two strings

• To convert a string to uppercase

• To remove spaces from the start and end of a string