Question

Define a wrapper class. 

Answer 1

The Java programming language uses wrapper classes included in the java.lang library package. The wrapper class includes a primitive data type. When creating an object from a wrapper class, a field in memory is allocated to store primitive data.

For example, 'Integer' is a wrapper class that includes the primitive data type 'int' and the following functions: 

Integer.parseInt() // to convert a String into integer data type 
Integer.toString() // to convert an integer data type to a String