What are the different types of constant variables and functions in Java?

In Java, constants, variables, and functions can have different types. Here are some common types:

Constant types:

1. Integral constants: this includes integer types (byte, short, int, long) and character types (char).
2. Floating point constants: include float and double data types.
3. String constants are sequences of characters enclosed in double quotation marks.
4. Boolean constants: consisting of true and false.

Variable Type:

1. Integer variables include integer types (byte, short, int, long) and character types (char).
2. Floating point variables include floating point types such as float and double.
3. String variable: a sequence of characters represented using the String data type.
4. Boolean variables: values represented as true or false using the boolean data type.

Function type:

1. Void functions do not return a value and are indicated by using the void keyword.
2. Integer function: returns a value of integer type (byte, short, int, long).
3. Floating-point function: returns values of floating-point types (float, double).
4. String functions: return values of type String.
5. Boolean function: returns a value of either true or false in boolean type.