I was trying to implement a controller test to guarantee that it would return the http 200 code, but when trying to run the test I received a NullPointerException exception.
Debugging the code I found that the MockMvc was null.
I already tried to add annotations like @SpringBootTest, @AutoConfigureMockMvc, @WebMvcTest, @ExtendWith and the MockMvc was still null and now I don't know what else to do to solve this problem
Note: I'm learning about these test things so if there's something bad in the code I'd appreciate it if you let me know
Here is my test code:
`
@ExtendWith(MockitoExtension.class)
@WebMvcTest(BookController.class)
@AutoConfigureMockMvc
@SpringBootTest
public class TestControlBook {
@Autowired
private MockMvc mockMvc;
@Test
public void testListBooks() throws Exception{
Response ResultActions = mockMvc.perform(MockMvcRequestBuilders.get("/api/books/list"));
response.andExpect(MockMvcResultMatchers.status().isOk());
}
}
here is my controller code:
`@RestController
@RequestMapping("/api/books")
public class BookController {
private BookService bookService;
public BookController(BookService bookService) {
this.bookService = bookService;
}
@GetMapping("/list")
private ResponseEntity<Object> listBooks(){
try {
return ResponseEntity.status(HttpStatus.OK).body(bookService.listBooks());
}
catch (Exception e){
return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body("An error occurred while trying to list the books, please try again later");
}
}
}
and here is my pom.xml:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.0.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.tdd</groupId>
<artifactId>exemplo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>TDD Exemplo</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>11</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>3.0.0</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>com.mysql</groupId>
<artifactId>mysql-connector-j</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.security</groupId>
<artifactId>spring-security-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter-engine</artifactId>
<version>5.2.0</version>
</dependency>
<dependency>
<groupId>org.mockito</groupId>
<artifactId>mockito-junit-jupiter</artifactId>
<version>4.6.1</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>`
```
I managed to solve the problem, what was happening was that the annotations were in conflict, causing the MockMvc not to be assigned. In addition, I changed some things so that the code was more readable and better.
The code is now like this: