Java - Useful code

// String Input 1 //
InputStreamReader isr = new InputStreamReader(System.in);
BufferedReader in = new BufferedReader(isr);
String str;
str = in.readLine();
System.out.println(str);

// String Input 2 //
Scanner scan = new Scanner(System.in);
String str = scan.nextLine();
System.out.println(str);

// if String equals //
if(str.equals("apple"))

// Converting to Int //
int num = Integer.parseInt(str);

// Random number //
Random r = new Random();
int randomNum = Math.abs(r.nextInt() % 3); // 0 -> 2

// Formula for percentage //
DecimalFormat fmt = new DecimalFormat("###.#%");
System.out.println(fmt.format(30.0/80.0));

-------------> 37.5%