97. Introducing record patterns for instanceof

In order to introduce record patterns, we need a more complex record than the one we’ve used so far, so here’s one:

public record Doctor(String name, String specialty) 
  implements Staff {}

This record implements the Staff interface as any other employee of our hospital. Now, we can identify a certain doctor in the old-fashioned style via instanceof as follows:

public static String cabinet(Staff staff) {
  if (staff instanceof Doctor) {
    Doctor dr = (Doctor) staff;
    return "Cabinet of " + dr.specialty() 
      + ". Doctor: " + dr.name();
  }
  ...
}

But, as we know from Chapter 2, Problems 58-67, JDK has introduced type patterns that can be used for instanceof and switch. So, in this particular case, we can rewrite the previous code via type patterns as follows:

public static String cabinet(Staff staff) {
  if (staff instanceof Doctor dr) { // type pattern matching
    return...