There are two types of Java virtual machines that can be handled, one is the original type (Primitive Types) and one is the reference type (Reference Types).
Correspondingly, there are two types of values that have primitive values (Primitive values) and reference values (Reference values) that can be used for variable assignment, parameter passing, method return, and operation.
Primitive type and value
The original data types supported by the Java Virtual machine include numeric types, Boolean types, and ReturnAddress types.
Numeric types include: integer types and floating-point types.
Integer types include:
1, byte
2. Short
3, int
4, long
5, Char
Floating-point types:
1, float
2, double
Boolean Type: Boolean
ReturnAddress type: An opcode (Opcode) that represents a bytecode instruction. Of all the primitive types supported by the virtual machine, only the returnaddress type cannot correspond directly to the data type of the Java language.
Reference type and value
There are three types of reference in a Java Virtual machine: Class Types, array type (Types), and interface type (Interface Types).
The values of these reference types are dynamically created by class instances, array instances, and class instances or array instances that implement an interface, respectively. The default value for a reference type is null.
Primitive types in Java (Primitive Types) and reference types (Reference Values)