Java Logical Operator

The && and || logical operators, meaning they don't evaluate the right hand side if it isn't necessary. Also called as short-circuit logical operator.

The & and | operators, when used as logical operators, always evaluate both sides.

  public static void main(String[] args) {
    if (singleDigit(1) & singleDigit(22)) {
      System.out.println("OK");
    }
  }

  private static boolean singleDigit(int ii) {
    System.out.println("number: " + ii);
    return ii<10;
  }

The above code will print

number: 1
number: 22