GH-725 Fix getNames() method to properly compute available function names

Resolves #725

spring-cloud-function-samples/function-sample-functional-aws-routing/src/main/java/example/FunctionConfiguration.java

@@ -0,0 +1,59 @@
+package example;
+
+import java.util.function.Function;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.cloud.function.context.FunctionRegistration;
+import org.springframework.cloud.function.context.FunctionType;
+import org.springframework.cloud.function.context.MessageRoutingCallback;
+import org.springframework.cloud.function.context.MessageRoutingCallback.FunctionRoutingResult;
+import org.springframework.cloud.function.json.JsonMapper;
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.support.GenericApplicationContext;
+import org.springframework.messaging.Message;
+
+@SpringBootApplication
+public class FunctionConfiguration implements ApplicationContextInitializer<GenericApplicationContext> {
+
+	/*
+	 * You need this main method or explicit <start-class>example.FunctionConfiguration</start-class>
+	 * in the POM to ensure boot plug-in makes the correct entry
+	 */
+	public static void main(String[] args) {
+		SpringApplication.run(FunctionConfiguration.class, args);
+	}
+
+	public Function<String, String> uppercase() {
+		return value -> value.toUpperCase();
+	}
+
+	public Function<String, String> reverse() {
+		return value -> new StringBuilder(value).reverse().toString();
+	}
+
+	public static class RoutingCallback implements MessageRoutingCallback {
+		@Override
+		public FunctionRoutingResult routingResult(Message<?> message) {
+			String payload = new String((byte[]) message.getPayload());
+			System.out.println("==> Will be routing based on payload: " + payload);
+			return payload.contains("uppercase")
+					? new FunctionRoutingResult("uppercase")
+							: new FunctionRoutingResult("reverse");
+		}
+	}
+
+	@Override
+	public void initialize(GenericApplicationContext applicationContext) {
+		System.out.println("==> Initializing");
+		applicationContext.registerBean(MessageRoutingCallback.class,
+				() -> new RoutingCallback());
+		applicationContext.registerBean("uppercase", FunctionRegistration.class,
+                () -> new FunctionRegistration<>(uppercase()).type(
+                        FunctionType.from(String.class).to(String.class)));
+		applicationContext.registerBean("reverse", FunctionRegistration.class,
+                () -> new FunctionRegistration<>(reverse()).type(
+                        FunctionType.from(String.class).to(String.class)));
+	}
+}