improvement BAEL-2897 (#6795)

* added example code for BAEL-2083

* updated example code for BAEL-2083

* added example code for BAEL-2849

* updated the example code with data.sql

* improvement BAEL-2897

* updated the persistence module

* updated readme

persistence-modules/spring-boot-persistence-h2/src/test/java/com/baeldung/SpringBootH2IntegrationTest.java

@@ -0,0 +1,50 @@
+package com.baeldung;
+
+import com.baeldung.h2db.springboot.SpringBootH2Application;
+import com.baeldung.h2db.springboot.daos.UserRepository;
+import com.baeldung.h2db.springboot.models.User;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import java.util.List;
+
+import static org.junit.Assert.*;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = SpringBootH2Application.class)
+public class SpringBootH2IntegrationTest {
+
+    @Autowired
+    private UserRepository userRepository;
+
+    @Test
+    public void contextLoads() { }
+
+    @Test
+    public void givenUserProfile_whenAddUser_thenCreateNewUser() {
+        User user = new User();
+        user.setFirstName("John");
+        user.setLastName("Doe");
+        userRepository.save(user);
+        List<User> users = (List<User>) userRepository.findAll();
+        assertFalse(users.isEmpty());
+
+        String firstName = "Aliko";
+        String lastName = "Dangote";
+        User user1 = userRepository.findById(users.get(0).getId()).get();
+        user1.setLastName(lastName);
+        user1.setFirstName(firstName);
+        userRepository.save(user1);
+
+        user = userRepository.findById(user.getId()).get();
+        assertEquals(user.getFirstName(), firstName);
+        assertEquals(user.getLastName(), lastName);
+
+        userRepository.deleteById(user.getId());
+        assertTrue( ((List<User>) userRepository.findAll()).isEmpty());
+    }
+
+}

persistence-modules/spring-boot-persistence-h2/src/test/java/com/baeldung/SpringContextIntegrationTest.java

@@ -0,0 +1,19 @@
+package com.baeldung;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.support.AnnotationConfigContextLoader;
+import org.springframework.test.context.web.WebAppConfiguration;
+
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(loader = AnnotationConfigContextLoader.class)
+@WebAppConfiguration
+public class SpringContextIntegrationTest {
+
+    @Test
+    public void whenSpringContextIsBootstrapped_thenNoExceptions() {
+    }
+}