type of data
Data type classification
Java data types are divided into two categories:
- Basic data types include: integers, floating point, character, Boolean.
- Reference data types : a class, arrays, interfaces.
Basic data types
Four eight basic data types: as shown below
Precautions:
- String is not a basic type, but reference types.
- Float may only be an approximation, not an exact value.
- The number of bytes of data does not necessarily correlate with the range of, for example, a wider range than the data float long, but float is 4 bytes, long 8 bytes.
- Among the default floating-point type is double. If you must use a float, you need to add a suffix F. If is an integer, the default type int, if we must use the long type, you need to add a suffix L. We recommend the use of capital letters suffix.