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

jmeter/src/test/java/com/baeldung/JmeterIntegrationTest.java

@@ -0,0 +1,36 @@
+package com.baeldung;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.mock.web.MockHttpServletResponse;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.web.context.WebApplicationContext;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@SpringBootTest
+class JmeterIntegrationTest {
+
+	MockMvc mvc;
+
+	public JmeterIntegrationTest(WebApplicationContext wac) {
+		this.mvc = MockMvcBuilders.webAppContextSetup(wac).build();
+	}
+
+	@Test
+	void whenCallingTestController_thenWeShouldRecieveRandomizedResponse() throws Exception {
+		MockHttpServletResponse response = mvc.perform(get("/api/test"))
+		  .andDo(print())
+		  .andExpect(status().isOk())
+		  .andReturn()
+		  .getResponse();
+
+		assertThat(response.getContentAsString())
+		  .contains("Test message...");
+	}
+
+}