In Java, there are two types of casting:
Widening Casting (automatically)
- converting a smaller type to a larger type size
byte -> short -> char -> int -> long -> float -> double
- Widening casting is done automatically when passing a smaller size type to a larger size type:
Example
public class MyClass {
public static void main(String[] args) {
int myInt = 9;
double myDouble = myInt; // Automatic casting: int to double
System.out.println(myInt); // Outputs 9
System.out.println(myDouble); // Outputs 9.0
}
}
Narrowing Casting (manually)
- Converting a larger type to a smaller size type
double -> float -> long -> int -> char -> short -> byte
- Narrowing casting must be done manually by placing the type in parentheses in front of the value:
Example
public class MyClass {
public static void main(String[] args) {
double myDouble = 9.78;
int myInt = (int) myDouble; // Manual casting: double to int
System.out.println(myDouble); // Outputs 9.78
System.out.println(myInt); // Outputs 9
}
}
