Eight data types and corresponding bytes

Byte:

Size: 1 byte

The value ranges from -128 to 127

Short:

Size: 2 bytes

Range: -2^15 to 2^15-1

Int: Size: 4 bytes

Range: -2^31 to 2^31-1

Long: Size: 8 bytes

Range: -2^63 to 2^63-1

Float: Size: 4 bytes

Range: -2^63 to 2^63-1

double

Size: 8 bytes

Char:

Size: 2 bytes

Range: \u000 ~ \ uFFF

boolean

Size: 4 bytes alone, 1 byte in the array

The reason is described in the Java Virtual Machine Specification: “The Boolean data type is defined, but only very limited support is provided for it. There are no special bytecode instructions for Boolean values in the Java Virtual machine. Boolean values operated on by Java language expressions are replaced by Java VIRTUAL machine int data types after compilation. Boolean arrays are encoded as Java virtual machine byte arrays. Each element Boolean element takes 8 bits “.