Java — Type Casting

Widening (implicit)

int myInt = 9;
double myDouble = myInt;  // Automatic casting: int to double
System.out.println(myDouble);  // 9.0

Narrowing (explicit)

double myDouble = 9.78d;
int myInt = (int) myDouble;  // Manual casting: double to int
System.out.println(myInt);  // 9

Common conversions

// int to double
double d = 42;

// double to int
int i = (int) 3.99;

// int to String
String s = String.valueOf(42);

// String to int
int num = Integer.parseInt("42");

// String to double
double dbl = Double.parseDouble("3.14");

Mini Practice

1. Convert int to double
2. Convert double to int
3. Convert number to String
4. Parse String to number

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Continue with Math - Math operations.