Why is the output of this code true false?

Question

Hey, I recently got this code in a java challenge. Why does it output true false? I can't think of anything that makes sense to me.
https://code.sololearn.com/c3wjKZ0hsULV/?ref=app

Answer 1

Integers are cached in range -128 to 127 and every variable has the same memory allocation
/////
Java doc source:

IntegerCache.low = -128;
IntegerCache.high = 127;

public static Integer valueOf(int i) {
if (i >= IntegerCache.low && i <= IntegerCache.high)
return IntegerCache.cache[i + (-IntegerCache.low)];
return new Integer(i);
}
/////
If value is in range between -128 to 127 method returns cached object (the same memory allocation every time), otherwise create new object.

So the best way to compare objects is to use method .equals().

Answer 2

True if type is int

https://code.sololearn.com/c7124lp2wxr2/?ref=app

I guess the byte of the object of class Integer is limited : 8 bytes = 1 byte for sign(+/-) + 7 binary digits
So cannot store 128 correctly

edit: Michal 's equals() method works👍
https://code.sololearn.com/cL76j0ujYduw/?ref=app