Fixed Code

src/main/java/com/capgemini/tdd/demo/controllers/GreetingController.java

@@ -4,6 +4,7 @@
 
 import com.capgemini.tdd.demo.models.Greeting;
 
+import com.capgemini.tdd.demo.models.TalkyNumber;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
@@ -19,4 +20,12 @@ public Greeting greeting(@RequestParam(value="name", defaultValue="World") Strin
         return new Greeting(counter.incrementAndGet(),
                 String.format(template, name));
     }
+
+
+    @RequestMapping("/talkynumbers")
+    public TalkyNumber talkynumbers(@RequestParam(value = "number", defaultValue = "1") String number) {
+        return new TalkyNumber(counter.incrementAndGet(),
+                Integer.parseInt(number));
+    }
 }
+

src/main/java/com/capgemini/tdd/demo/models/TalkyNumber.java

@@ -0,0 +1,24 @@
+package com.capgemini.tdd.demo.models;
+
+import com.capgemini.tdd.demo.services.NumberService;
+
+public class TalkyNumber {
+    private final long id;
+    private final int number;
+    private NumberService talkynumbers = new NumberService();
+
+    public TalkyNumber(long id, int number) {
+        this.id = id;
+        this.number= number;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public String getNumber() {
+        return talkynumbers.convert(number);
+    }
+}
+
+

src/main/java/com/capgemini/tdd/demo/services/NumberService.java

@@ -68,7 +68,7 @@ public String convert(int num){
                 if(num >= 100){
                     output += ", ";
                 }
-                else{
+                else if (num > 0) {
                     output += " and ";
                 }