Q:

Java : A pipe used in a print statement in java? 

What is it when a pipe is used in print statement in java?  For example
System.out.println(6 | 3);

Output : 7
System.out.println(6 | 4);

Output : 6

A:

Quite simple 
System.out.println(6 | 3);
Performing "OR" operation of two values using corresponding binary values. 
6 - 0 1 1 0
3 - 0 0 1 1 (OR)
-------------
    0 1 1 1 (7)
-------------

System.out.println(6 | 4);
6 - 0 1 1 0
3 - 0 1 0 0 (OR)
-------------
    0 1 1 0 (6)
-------------

