Learn Java Programming - Autoboxing Tutorial
In my Primitive Wrapper Classes Tutorial I discussed the basics of how the wrapper classes work. Quick refresher ... int i = 41; Integer ref = new Integer(i); // box the primitive int type value into an Integer object i = ref.intValue(); // unbox the int value from the Integer object
Based on the code sample from above, it would become quite tedious manually exchanging values from primitive types to objects and vice-versa. Say hello to the concept of autoboxing and auto-unboxing! Java autoboxing automatically encapsulates primitive data types into object state for us, Java also does the dirty work by auto-unboxing object state into a primitive value. Autoboxing opens a whole new world of possibilities, especially in future concepts that utilize anything related to Generics. Don't worry about Generics yet, I will discuss them when the time is right. Here is the same thing as above with autoboxing ... Integer ref = 41; // autobox the primitive int type value into an Integer object int i = ref; // auto-unbox a primitive int value from an Integer object