title: what does the test folder does in spring boot project?
body: <p>i have just created the spring boot project and there is a folder named test inside the src. what does it do?</p>
  
  <pre><code>import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.springframework.boot.test.context.SpringBootTest;
  import org.springframework.test.context.junit4.SpringRunner;
  
  @RunWith(SpringRunner.class)
  @SpringBootTest
  public class GprocApplicationTests {
  
  @Test
  public void contextLoads() {
  }
  
  }
  </code></pre>
  
  <p>while creating the spring boot project, there exists the test folder inside the src folder of the project. Inside the test folder there is a class annotated with @RunWith(SpringRunner.class) @SpringBootTest. what does it do?</p>