how to force the user to enter only strings in java

Answer 1

Question is not clear...

Answer 2

You can take this as a solution but you can't force a user to enter only string on a console :

System.out.println("Enter your name: ");
String name = in.nextLine();
while(!name.matches("[a-zA-Z]+")){
System.out.println("Please enter a valid name!");
name = in.nextLine();
}