When to use wrapper class and primitive type

java wrapper primitive-types
Gopi picture Gopi · Oct 15, 2009 · Viewed 76.7k times · Source

When I should go for wrapper class over primitive types? Or On what circumstance I should choose between wrapper / Primitive types?

Answer

pstanton picture pstanton · Oct 15, 2009

Others have mentioned that certain constructs such as Collections require objects and that objects have more overhead than their primitive counterparts (memory & boxing).

Another consideration is:

It can be handy to initialize Objects to null or send null parameters into a method/constructor to indicate state or function. This can't be done with primitives.

Many programmers initialize numbers to 0 (default) or -1 to signify this, but depending on the scenario, this may be incorrect or misleading.

This will also set the scene for a NullPointerException when something is being used incorrectly, which is much more programmer-friendly than some arbitrary bug down the line.

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