Rock, Paper, Scissors Game Java

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!!");
  }