Java Autoboxing

Internal

• Java

Overview

Java has a mechanism called boxing that converts primitive types (such as int) into their corresponding reference types (java.lang.Integer). The opposite operation, converting reference types into their corresponding primitive types is called unboxing.

Autoboxing is a mechanism that performs boxing and unboxing automatically.

Autoboxing comes with a performance cost. Boxed values are wrappers around primitive types, and are stored on the heap. Therefore, boxed values use more memory and requires additional memory lookups to fetch the wrapped primitive type.

Autoboxing and Streams API

The Streams API has specialized stream types and API calls for primitive types, to avoid unnecessary autoboxing.

TODO

• https://docs.oracle.com/javase/tutorial/java/data/autoboxing.html