I would recommend making Rock, Paper and Scissors objects. The objects would have the logic of both translating to/from Strings and also “knowing” what beats what. The Java enum is perfect for this.
public enum Type{
ROCK, PAPER, SCISSOR;
public static Type parseType(String value){
//if /else logic here to return either ROCK, PAPER or SCISSOR
//if value is not either, you can return null
}
}
The parseType
method can return null
if the String is not a valid type. And you code can check if the value is null and if so, print “invalid try again” and loop back to re-read the Scanner.
Type person=null;
while(person==null){
System.out.println("Enter your play: ");
person= Type.parseType(scan.next());
if(person ==null){
System.out.println("invalid try again");
}
}
Furthermore, your type enum can determine what beats what by having each Type
object know:
public enum Type{
//...
//each type will implement this method differently
public abstract boolean beats(Type other);
}
each type will implement this method differently to see what beats what:
ROCK{
@Override
public boolean beats(Type other){
return other == SCISSOR;
}
}
...
Then in your code
Type person, computer;
if (person.equals(computer))
System.out.println("It's a tie!");
}else if(person.beats(computer)){
System.out.println(person+ " beats " + computer + "You win!!");
}else{
System.out.println(computer + " beats " + person+ "You lose!!");
}