why there is need of wrapper classes in java code example

Example: wrapper classes in java

Wrapper classes: classes that are dedicated to primitives        
Byte, Short, Integer, Long, Float, Double, Character, Boolean
presented in "java.lang" package
AutoBoxing: converting primitive values to wrapper class
		int a = 100;
		Integer b = a  // auto boxing
Unboxing: converting wrapper class value to primitives
		Integer a = 100;
		int b = a;  // unboxing
	int a = 100;
	double b = a;    // none