integer types

■ There are five Java integer types. Their sizes and ranges are:

byte 8 bits -128 to +127

short 16 bits -32,768 to +32,767

int 32 bits -2 to the 31^st to +2 to the 31^st –1

long 64 bits -2 to the 63^rd to +2 to the 63^rd –1

char 16 unsigned bits \u0000 to \uffff

■ You cannot put double quotes around a char, as chars are always encased in single quotes. i.e.

char A = '\u00C1'; or char c = '2'; works

char A = "\u00C1"; or char c = "2"; won't compile

■ If they are being incremented in a for loop, integers will simply run over their maximums and become negative. No errors are generated. i.e.

for ( byte b = 0; ; b++) ; will not stop at byte's maximum value of 127, or ever.

Such loops are difficult to code in actual programs because the compiler will detect the unreachable statements below them.

■ Integer divide by zero in Java always results in an ArithmeticException being thrown. i.e.

int x = 5, y = 0, z;

z = x / y; compiles but throws the exception.