Why are 2 Long variables not equal with == operator in Java?

Question

I got a very strange problem when I\'m trying to compare 2 Long variables, they always show false and I can be sure they have the same number value by debugging in Eclipse:<

Answer 1

because == compares reference value, and smaller long values are cached

 public static Long  valueOf(long l) {
     final int offset = 128;
     if (l >= -128 && l <= 127) { // will cache
         return LongCache.cache[(int)l + offset];
     }
     return new Long(l);
 }

so it works for smaller long values

Also See

• Integer wrapper class and == operator - where is behavior specified?