english version

Addition.java

+public class Addition{
+	
+		//All java programs start with main method
+		public static void main(String[] args){
+			if(args.length !=2){
+				System.out.println("Give two whole number arguments!");
+				System.exit(0); //This quits the program
+			}
+			
+			//Changes the arguments to integers
+			//Note: the program crashes if the arguments are not whole numbers
+			int num1 = Integer.parseInt(args[0]);
+			int num2 = Integer.parseInt(args[1]);
+			
+			int sum = num1+num2; 
+			//print the sum
+			System.out.println("Numbers "+ num1 + " and " + num2+" sum is: " +sum);
+			
+			//program ends
+		}
+	
+}
\ No newline at end of file

Factorial.java

+
+public class factorial{
+
+	/*
+	 * Prints the factorial of given argument
+	 */
+	public static void main(String[] args){
+		int num = Integer.parseInt(args[0]);
+		int factorial =1
+		for(int i = 1; i<=num;i++){
+			factorial = factorial*i;
+		}
+		System.out.println(factorial);
+	
+	}

HelloWorld.java

+
+class HelloWorld{
+
+	public static void main(String[] args){
+		System.out.println("Hello World!")
+	}	
+}