Number in java how it work without a subclass? -


i want know why result of code: 

number x = 3; system.out.println(x.intvalue()); system.out.println(x.doublevalue());

generates

3
3.0

as number abstract class in java.

so when need use - use it's subclasses integer, double ...etc. want know how part of code works:

number x = 3;

auto boxing.

so when 

number x = 3;

that gets compiled 

number x = new integer(3);

number in java how work without subclass?

that wrong assumption. number class have subclasses. if @ definition of integer class.

look @ definition of integer class 

public final class integer extends number

it sublcass of number gets compiled fine.


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