Why does the output value of (a) change when you use the | operator instead of the operator || is used?

Question

int a = 2;
int b = 3;
if ((a < b) || (++ a == b)) {
System . out. println ("a = " + a);
System . out. println ("b = " + b);
}
:::RESULT:::
a = 2
b = 3
UNDERSTOOD

but when:
int a = 2;
int b = 3;
if ((a < b) | (++ a == b)) {
System . out. println ("a = " + a);
System . out. println ("b = " + b);
}
:::RESULT:::
a = 3
b = 3
WHY?
How is it calculated exactly, please?

Answer 1

First of all the result of the first code is a = 2, b = *4*.
And second if I understood this then it works as || operator but it doesn't stop if it already found a true part of the if statement.

Answer 2

can you tell me what does that" if((a<b)l(++a==b))"means