Midterm Helps You Can See During the Test

• Setup to read something from the screen:
  • In Java: there are 2 commands needed:
    
  • before the class starts, import the scanner class using: import java.util.Scanner;
  • inside the method, create a scanner object using: Scanner kbd = new Scanner(System.in);

   

• Read something from the screen:
  • In Java: <your variable> = < name of the scanner you created above>.nextLine();
  • Use the scanner method that matches your variable type.
  • example to get the whole line: myStringVar = kbd.nextLine();
  • example to get the next word: myStringVar = kbd.next();
  • example to get the next double: mydoubleVar = kbd.nextDouble();
  • example to get the next int: myIntVar = kbd.nextInt();
  • See Sun's page on scanner for much more
    

• Math
  • absolute value: Math.abs(#)
  • random: Math.random()
  • minimum: Math.min(#,#)
  • maximum: Math.max(#,#)
  • raise to a power: Math.max(x,y) : Note: x is raised to y.
    

• Strings
  • stringvar.charAt(3) // will return a character
  • stringvar.length() // will return an integer
  • stringvar.toUpperCase() // will return a String that is all uppercase
  • stringvar.toLowerCase() // will return a String that is all lowercase
  • stringvar.subString(2) // will return a String starting in position 2 to the end
  • stringvar.subString(2, 5) // will return a String starting in position 2 and ending in position 4
  • stringvar.equals(somethingOtherString) // will return either true or false (a boolean)

(See your Java Tools)