Java Integer Wrapper Class Related -

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public class testme{  public static void main(string[] args)  {    integer = 128;    integer j = 128;     integer k = 12;    integer l = 12;     system.out.println(i == j);      system.out.println(k == l);   } }

i'm getting output: false true

why 1st 1 false , 2nd 1 true?

see: http://javapapers.com/java/java-integer-cache/

short answer:

in java 5, new feature introduced save memory , improve performance integer type objects handlings. integer objects cached internally , reused via same referenced objects.

this applicable integer values in range between –127 +127.

this integer caching works on autoboxing. integer objects not cached when built using constructor.


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