Is int an object in Java?

java inheritance primitive
soandos picture soandos · Oct 9, 2011 · Viewed 21.2k times · Source

More precisely, is int a part of the Integer class (a stripped down version or something) or is it something else entirely?

I am aware that int is a value type and Integer a reference type, but does int inherit from Object anyway?

(I am assuming that in this regard int, long, boolean etc are all similar. int was just chosen for convenience)

Answer

mikek3332002 picture mikek3332002 · Oct 9, 2011

  • The basic types in Java are not objects and does not inherit from Object.

  • Since Java 1.5 introduced allowed auto boxing between int and Integer(and the other types).

  • Because ints aren't Objects that can't be used as generic type parameters eg the T in list<T>

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