Added a demo of using the java.util.function.Consumer interface

bsnyder · bsnyder · commit 177c8b53a12c · 2015-01-16T17:59:20.000-07:00
diff --git a/src/main/java/org/bsnyder/java18/examples/ConsumerDemo.java b/src/main/java/org/bsnyder/java18/examples/ConsumerDemo.java
@@ -0,0 +1,47 @@
+package org.bsnyder.java18.examples;
+
+import java.util.function.Consumer;
+
+class Customer {
+    private String ssn;
+    private Double balance;
+
+    public Customer(String ssn, Double balance) {
+        this.ssn = ssn;
+        this.balance = balance;
+    }
+
+    public String getSsn() {
+        return ssn;
+    }
+
+    public Double getBalance() {
+        return balance;
+    }
+
+    public void setBalance(Double balance) {
+        this.balance = balance;
+    }
+
+}
+
+class Bank {
+
+    public void updateBalance(Customer customer, Consumer<Customer> consumer) {
+        System.out.println("              SSN: " + customer.getSsn());
+        System.out.println("Balance before tx: " + customer.getBalance());
+        consumer.accept(customer);
+        System.out.println(" Balance after tx: " + customer.getBalance());
+    }
+}
+
+public class ConsumerDemo {
+
+    public static void main(String[] args) {
+        Bank bank = new Bank();
+        Customer customer = new Customer("000-00-0000", 5000.0);
+        bank.updateBalance(customer, c -> c.setBalance(c.getBalance() + 2000.0));
+        System.out.println("-----------------------");
+        bank.updateBalance(customer, c -> c.setBalance(c.getBalance() - 500.0));
+    }
+}
