OnJava8-Examples/generics/BankTeller.java
2015-05-29 14:18:51 -07:00

59 lines
1.6 KiB
Java

//: generics/BankTeller.java
// ©2015 MindView LLC: see Copyright.txt
// A very simple bank teller simulation.
import java.util.*;
import net.mindview.util.*;
class Customer {
private static long counter = 1;
private final long id = counter++;
private Customer() {}
@Override
public String toString() { return "Customer " + id; }
// A method to produce Generator objects:
public static Generator<Customer> generator() {
return Customer::new; // Constructor reference
}
}
class Teller {
private static long counter = 1;
private final long id = counter++;
private Teller() {}
@Override
public String toString() { return "Teller " + id; }
// A single Generator object:
public static Generator<Teller> generator = Teller::new;
}
public class BankTeller {
public static void serve(Teller t, Customer c) {
System.out.println(t + " serves " + c);
}
public static void main(String[] args) {
Random rand = new Random(47);
Queue<Customer> line = new LinkedList<>();
Generators.fill(line, Customer.generator(), 15);
List<Teller> tellers = new ArrayList<>();
Generators.fill(tellers, Teller.generator, 4);
for(Customer c : line)
serve(tellers.get(rand.nextInt(tellers.size())), c);
}
} /* Output:
Teller 3 serves Customer 1
Teller 2 serves Customer 2
Teller 3 serves Customer 3
Teller 1 serves Customer 4
Teller 1 serves Customer 5
Teller 3 serves Customer 6
Teller 1 serves Customer 7
Teller 2 serves Customer 8
Teller 3 serves Customer 9
Teller 3 serves Customer 10
Teller 2 serves Customer 11
Teller 4 serves Customer 12
Teller 2 serves Customer 13
Teller 1 serves Customer 14
Teller 1 serves Customer 15
*///:~