[BAEL-19881] - Rename spring-mvc-simple modules

spring-mvc-basics-4/src/main/java/com/baeldung/optionalpathvars/ArticleViewerController.java

@@ -0,0 +1,23 @@
+package com.baeldung.controller.optionalpathvars;
+
+import static com.baeldung.controller.optionalpathvars.Article.DEFAULT_ARTICLE;
+
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class ArticleViewerController {
+
+    @RequestMapping(value = {"/article", "/article/{id}"})
+    public Article getArticle(@PathVariable(name = "id") Integer articleId) {
+
+        if (articleId != null) {
+            return new Article(articleId);
+        } else {
+            return DEFAULT_ARTICLE;
+        }
+
+    }
+
+}