无法自动装配 MapStruct 映射器

Question

I was following this tutorial about the partial update. As instructed, I created mapper interface with proper annotations.

Here's the mapper

@Mapper(componentModel = "spring")
public interface UserEntityMapper {
  
  @Mapping(source = "password", target = "password")
  @BeanMapping(nullValuePropertyMappingStrategy = NullValuePropertyMappingStrategy.IGNORE)
  void updatePasswordFromDTO(PasswordResetRequest dto, @MappingTarget User entity);
}

As per the tutorial, @Mapper(componentModel = "spring") generates mapper as a Spring bean that can be retrieved via @Autowired .

But when I tried to do same in my service layer class ,

@Service
@Transactional
public class AccountServiceImpl implements IAccountService {
  ...
  @Autowired
  private UserEntityMapper userMapper;
  ...
}

I get this error, my application failed to start.

***************************
APPLICATION FAILED TO START
***************************

Description:

Field userMapper in com.application.services.AccountServiceImpl required a bean of type 'com.application.mappers.UserEntityMapper' that could not be found.

The injection point has the following annotations:
    - @org.springframework.beans.factory.annotation.Autowired(required=true)


Action:

Consider defining a bean of type 'com.application.mappers.UserEntityMapper' in your configuration.

And at last, here's pom.xml of my project.

<?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>2.5.5</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.myproject</groupId>
    <artifactId>myproject</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>authentication-template</name>
    <description>Description</description>
    <properties>
        <java.version>11</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-validation</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </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>

        <!-- https://mvnrepository.com/artifact/io.jsonwebtoken/jjwt -->
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt</artifactId>
            <version>0.9.1</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-freemarker -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-freemarker</artifactId>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.mapstruct/mapstruct -->
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct</artifactId>
            <version>1.4.2.Final</version>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

I also tried these different solution, but same result.

1. Answer By @Som
2. Answer by @Gunnar

Edit 1

Here's @SpringBootApplication file.

@SpringBootApplication
@PropertySources(value = {
  @PropertySource("classpath:mail.properties"),
  @PropertySource("classpath:messages.properties"),
  @PropertySource("classpath:security.properties")
})
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

}

Edit 2

Package structure of the project

Please help, Thank you :)

Answer 1

There are several suggestions you can investigate. First, check if there is @Component in the class generated by mvn.

• If so, check if your application is configured to scan that package.
• If no, try to read the MapStruct documentation .

Answer 2

I have the dependency like below, all the things are Ok.

<dependency>
    <groupId>org.mapstruct</groupId>
    <artifactId>mapstruct</artifactId>
    <version>1.4.2.Final</version>
</dependency>

And in part of plugins.

 <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                    <annotationProcessorPaths>
                      <path>
                        <groupId>org.mapstruct</groupId>
                        <artifactId>mapstruct-processor</artifactId>
                        <version>1.4.2.Final</version>
                      </path>
                    </annotationProcessorPaths>
                </configuration>
            </plugin>
        </plugins>
    </build>

Answer 3

If the pom.xml you provided is the latest version, I think you are missing the step, that actually generates the MapStruct mappers from your definitions. You need to define it as part of the build setup as stated here https://mapstruct.org/documentation/installation/

You need to add that part to the build - plugins section

<plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.8.1</version>
            <configuration>
                <source>1.8</source> <!-- depending on your project -->
                <target>1.8</target> <!-- depending on your project -->
                <annotationProcessorPaths>
                    <path>
                        <groupId>org.mapstruct</groupId>
                        <artifactId>mapstruct-processor</artifactId>
                        <version>${org.mapstruct.version}</version>
                    </path>
                    <!-- other annotation processors -->
                </annotationProcessorPaths>
            </configuration>
        </plugin>

Also check your target/generated folders if the mappers are successfully generated

Answer 4

Added to plugins:

 <compilerArgs>
      <compilerArg>
             -Amapstruct.defaultComponentModel=spring
      </compilerArg>
 </compilerArgs>