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javanumbersdoubleinteger-overflowdouble-precision

different overflow policy for Double and Integer. why?

this code 

System.out.println(Double.MAX_VALUE+12345 == Double.MAX_VALUE);
System.out.println(Integer.MAX_VALUE+12345 == Integer.MAX_VALUE);

returns 

true
false

Please clarify this difference.

Solution

  • The rules are the same, it's just that Double.MAX_VALUE is so large that 12345 is roughly 300 orders of magnitude (10300 times) smaller. Adding a number that is so much smaller than Double.MAX_VALUE does not change its value. Adding a number that is of the same order of magnitude would make a difference, though:

    Double.MAX_VALUE + 1E300

    produces a positive infinity result, which is not the same as Double.MAX_VALUE (demo)