Q:

What does the sign ' | ' mean in java?

I have come across the code and I am wondering what does it do?
for(int i=1;i<32;i++){

    for(int j=1;j<32;j++){

        if(( i | j )==31){ // here the sing ' | '

         }
     }
  }

A:

'|' is a bitwise operator in java. 
You'll find a decent explanation here: https://www.tutorialspoint.com/java/java_basic_operators.htm
Not to be confused with '||' which means or.

