BAEL-4672 added content for JMeter extract data to file tutorial

jmeter/src/main/java/com/baeldung/controller/TestController.java

@@ -0,0 +1,18 @@
+package com.baeldung.controller;
+
+import com.baeldung.model.Response;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.UUID;
+
+import static java.lang.String.format;
+
+@RestController
+public class TestController {
+
+    @GetMapping("/api/test")
+    public Response test() {
+        return new Response(format("Test message... %s.", UUID.randomUUID()));
+    }
+}

jmeter/src/main/java/com/baeldung/model/Response.java

@@ -0,0 +1,40 @@
+package com.baeldung.model;
+
+import java.time.Instant;
+import java.util.UUID;
+
+public class Response {
+    private Instant timestamp;
+    private UUID uuid;
+    private String message;
+
+    public Response(String message) {
+        this.timestamp = Instant.now();
+        this.uuid = UUID.randomUUID();
+        this.message = message;
+    }
+
+    public Instant getTimestamp() {
+        return timestamp;
+    }
+
+    public void setTimestamp(Instant timestamp) {
+        this.timestamp = timestamp;
+    }
+
+    public UUID getUuid() {
+        return uuid;
+    }
+
+    public void setUuid(UUID uuid) {
+        this.uuid = uuid;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public void setMessage(String message) {
+        this.message = message;
+    }
+}