Rename implementation classes and update Jackson dependency to Jackson 2.

src/main/java/hello/Greeting.java

@@ -0,0 +1,21 @@
+package hello;
+
+public class Greeting {
+
+	private final long id;
+	private final String content;
+
+	public Greeting(long id, String content) {
+		this.id = id;
+		this.content = content;
+	}
+
+	public long getId() {
+		return id;
+	}
+
+	public String getContent() {
+		return content;
+	}
+
+}

src/main/java/hello/HelloWorldController.java

@@ -0,0 +1,23 @@
+package hello;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.ResponseBody;
+
+@Controller
+@RequestMapping("/hello-world")
+public class HelloWorldController {
+
+	private static final String template = "Hello, %s!";
+	private final AtomicLong counter = new AtomicLong();
+
+	@RequestMapping(method=RequestMethod.GET)
+	public @ResponseBody Greeting sayHello(@RequestParam(value="name", required=false, defaultValue="Stranger") String name) {
+		return new Greeting(counter.incrementAndGet(), String.format(template, name));
+	}
+	
+}