Conversions and Promotions - The Java Language Specification - page 116

• The numerical equality operators == and != (§ 15.21.1 )
• The integer bitwise operators & , ^ , and | (§ 15.22.1 )
• In certain cases, the conditional operator ? : (§ 15.25 )
Example 5.6.2-1. Binary Numeric Promotion
Click here to view code image
class Test {
public static void main(String[] args) {
int i = 0;
float f = 1.0f;
double d = 2.0;
// First int*float is promoted to float*float, then
// float==double is promoted to double==double:
if (i * f == d) System.out.println("oops");
// A char&byte is promoted to int&int:
byte b = 0x1f;
char c = 'G';
int control = c & b;
System.out.println(Integer.toHexString(control));
// Here int:float is promoted to float:float:
f = (b==0) ? i : 4.0f;
System.out.println(1.0/f);
}
}
This program produces the output:
7
0.25
The example converts the ASCII character G to the ASCII control-G (BEL), by mask-
ing off all but the low 5 bits of the character. The 7 is the numeric value of this control
character.