Answer 1

Hello devansh

Wrapper classes wrap around the primitive data types.
Examples you find in the oracle documentation

Wrapper class primitive data type
Integer int
Double double
Float float
Boolean boolean
...
And so on.

https://docs.oracle.com/javase/10/docs/api/index.html?overview-summary.html

Take a look at this website. In the search Segment input 'integer' for example.
You get the Documentation of the Wrapper class Integer. Read the details for understand how it's work.

Regards kiuziu