java basic data types

1. Data Type Classification

2. Shape Type

Byte data range representation 

floating point type

character type char

Character constants have three representations.

1. Specify character constants directly by a single character, such as 'A', 'b', '7';

2. Escape characters represent special character constants, such as '\n', '\\';

3. Directly use Unicode value representation, such as '\u5b8b';

 boolean type

Boolean type has only two values, true and false.