Java long Keyword
The Java long keyword is a primitive data types. The long data type is a 64-bit two's complement integer. Its default value is 0L and default size is 64 bits (8 byte). The range of a long value is -263 to 263-1.
Example: Create a long value
In the example below, variable x and y are created to store long values. Please note that, value with a "L" is used to represent the long value.
public class MyClass {
public static void main(String[] args) {
//creating long values
long x = 10l;
long y = 10L;
//printing variables
System.out.println("x = " + x);
System.out.println("y = " + y);
}
}
The output of the above code will be:
x = 10.5 y = 10.0
Example: Widening Casting (smaller to larger type)
A long value can be created by assigning a byte, a short or an int data to a long variable. The compiler implicitly typecast these data types to long as shown in the output.
public class MyClass {
public static void main(String[] args) {
byte num_byte = 10;
//Widening Casting
short num_short = num_byte;
int num_int = num_short;
long num_long = num_int;
//printing variables
System.out.println("num_byte = " + num_byte);
System.out.println("num_short = " + num_short);
System.out.println("num_int = " + num_int);
System.out.println("num_long = " + num_long);
}
}
The output of the above code will be:
num_byte = 10 num_short = 10 num_int = 10 num_long = 10
Example: Narrowing Casting (larger to smaller type)
For a larger data types like double and float, narrowing casting is required. The compiler explicitly typecast these data types to long as shown in the output.
public class MyClass {
public static void main(String[] args) {
double num_double = 10.5d;
//Narrowing Casting
float num_float = (float) num_double;
long num_long = (long) num_float;
//printing variables
System.out.println("num_double = " + num_double);
System.out.println("num_float = " + num_float);
System.out.println("num_long = " + num_long);
}
}
The output of the above code will be:
num_double = 10.5 num_float = 10.5 num_long = 10
❮ Java Keywords
