java - Can we change wrapper class into primitive data types? -


this question has answer here:

can change wrapper primitive ?if not happening in code 

int = integer.valueof(46); system.out.println(i);

i not getting error.

yes, called unboxing:

integer boxed = 10; // boxing int unboxed = boxed; // unboxing

boxing conversions described in jls 5.1.7; unboxing conversions described in jls 5.1.8.

note if try unbox null reference, nullpointerexception thrown:

integer boxed = null; int unboxed = boxed; // npe

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