Wrapper classes: classes that are dedicated to primitives
Byte, Short, Integer, Long, Float, Double, Character, Boolean
presented in "java.lang" package
AutoBoxing: converting primitive values to wrapper class
int a = 100;
Integer b = a // auto boxing
Unboxing: converting wrapper class value to primitives
Integer a = 100;
int b = a; // unboxing
int a = 100;
double b = a; // none
Integer number = new Integer(77);//int
Integer number2 = new Integer("77");//String
Float number3 = new Float(77.0);//double argument
Float number4 = new Float(77.0f);//float argument
Float number5 = new Float("77.0f");//String
Character c1 = new Character('S');//Only char constructor
Character c2 = new Character(1234);//COMPILER ERROR
Boolean b = new Boolean(true);//value stored - true
public class CommandLineArguments {
public static void main(String[] args) {
int a = Integer.parseInt(args[0]);
int b = Integer.parseInt(args[1]);
int sum = a + b;
System.out.println("Sum is " + sum);
}
}