// enumerations/People.java

// (c)2021 MindView LLC: see Copyright.txt

// We make no guarantees that this code is fit for any purpose.

// Visit http://OnJava8.com for more book information.

// {NewFeature} Preview in JDK 17

// Compile with javac flags:

// --enable-preview --source 17

// Run with java flag: --enable-preview

import java.util.*;

record Person(String name, int age) {}

public class People {

static String categorize(Person person) {

return switch(person) {

case Person p && p.age() > 40 // [1]

-> p + " is middle aged";

case Person p &&

(p.name().contains("D") || p.age() == 14)

-> p + " D or 14";

case Person p && !(p.age() >= 100) // [2]

-> p + " is not a centenarian";

case Person p -> p + " Everyone else";

};

}

public static void main(String[] args) {

List.of(

new Person("Dorothy", 15),

new Person("John Bigboote", 42),

new Person("Morty", 14),

new Person("Morty Jr.", 1),

new Person("Jose", 39),

new Person("Kane", 118)

).forEach(

p -> System.out.println(categorize(p))

);

}

}

/* Output:

Person[name=Dorothy, age=15] D or 14

Person[name=John Bigboote, age=42] is middle aged

Person[name=Morty, age=14] D or 14

Person[name=Morty Jr., age=1] is not a centenarian

Person[name=Jose, age=39] is not a centenarian

Person[name=Kane, age=118] is middle aged

*/