Automatic conversion of primitive types and their corresponding object wrapper classes (eg, int and Integer, double and Double, etc).
Autoboxing is a new feature java 1.5 . It is a capability to convert or cast between object wrapper and it’s primitive type.it was necessary to wrap a primitive type to a Wrapper class before adding it to a collection i.e is called Boxing and to unwrap it back to the primitive when it came out of the collection i.e unboxing.
Auto-boxing and Auto-Unboxing enables the primitive types to be converted into respective wrapper objects and the other way around.
Before jdk 1.5 we need to manual boxing.We have to write tedious coding for that.
example-
Integer vinay();
…
int i = vinay();
Difference between autoboxing and Casting–
Boxing – Boxing is when you use or make primitive type to a reference type
Casting – Casting is when you want one type to treated as another type, between primitive types and reference types