title: @Mapper not generating correctly the Implementation class
body: <p>I'm working in spring boot with Mappstruct and Lombok. When I use the Mapper anotation to auto implement the mapper class, the anotation is not generating correcty the mapper implementation for my classes.</p>
  <p>This is POM.xml</p>
  <pre><code>&lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;
  &lt;project xmlns=&quot;http://maven.apache.org/POM/4.0.0&quot; xmlns:xsi=&quot;http://www.w3.org/2001/XMLSchema-instance&quot;
  xsi:schemaLocation=&quot;http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd&quot;&gt;
  &lt;modelVersion&gt;4.0.0&lt;/modelVersion&gt;
  &lt;parent&gt;
      &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
      &lt;artifactId&gt;spring-boot-starter-parent&lt;/artifactId&gt;
      &lt;version&gt;2.3.5.RELEASE&lt;/version&gt;
      &lt;relativePath/&gt; &lt;!-- lookup parent from repository --&gt;
  &lt;/parent&gt;
  &lt;groupId&gt;com.domotichouse.app&lt;/groupId&gt;
  &lt;artifactId&gt;SpringDomoticHouse&lt;/artifactId&gt;
  &lt;version&gt;0.0.1-SNAPSHOT&lt;/version&gt;
  &lt;name&gt;SpringDomoticHouse&lt;/name&gt;
  &lt;description&gt;Spring proyect for the domotic of my house&lt;/description&gt;
  
  &lt;properties&gt;
      &lt;java.version&gt;11&lt;/java.version&gt;
      &lt;mapstruct.version&gt;1.3.1.Final&lt;/mapstruct.version&gt;
      &lt;lombok.version&gt;1.18.16&lt;/lombok.version&gt;
      &lt;log4j2.version&gt;2.13.3&lt;/log4j2.version&gt;
  &lt;/properties&gt;
  
  &lt;dependencies&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
          &lt;artifactId&gt;spring-boot-starter-data-jpa&lt;/artifactId&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
          &lt;artifactId&gt;spring-boot-starter-thymeleaf&lt;/artifactId&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
          &lt;artifactId&gt;spring-boot-starter-validation&lt;/artifactId&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
          &lt;artifactId&gt;spring-boot-starter-web&lt;/artifactId&gt;
      &lt;/dependency&gt;
  
      &lt;dependency&gt;
          &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
          &lt;artifactId&gt;spring-boot-devtools&lt;/artifactId&gt;
          &lt;scope&gt;runtime&lt;/scope&gt;
          &lt;optional&gt;true&lt;/optional&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;com.h2database&lt;/groupId&gt;
          &lt;artifactId&gt;h2&lt;/artifactId&gt;
          &lt;scope&gt;runtime&lt;/scope&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;mysql&lt;/groupId&gt;
          &lt;artifactId&gt;mysql-connector-java&lt;/artifactId&gt;
          &lt;scope&gt;runtime&lt;/scope&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.apache.logging.log4j&lt;/groupId&gt;
          &lt;artifactId&gt;log4j-to-slf4j&lt;/artifactId&gt;
          &lt;version&gt;${log4j2.version}&lt;/version&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.mapstruct&lt;/groupId&gt;
          &lt;artifactId&gt;mapstruct-jdk8&lt;/artifactId&gt;
          &lt;version&gt;${mapstruct.version}&lt;/version&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.mapstruct&lt;/groupId&gt;
          &lt;artifactId&gt;mapstruct-processor&lt;/artifactId&gt;
          &lt;version&gt;${mapstruct.version}&lt;/version&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.projectlombok&lt;/groupId&gt;
          &lt;artifactId&gt;lombok&lt;/artifactId&gt;
          &lt;version&gt;${lombok.version}&lt;/version&gt;
          &lt;optional&gt;true&lt;/optional&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
          &lt;artifactId&gt;spring-boot-starter-test&lt;/artifactId&gt;
          &lt;scope&gt;test&lt;/scope&gt;
          &lt;exclusions&gt;
              &lt;exclusion&gt;
                  &lt;groupId&gt;org.junit.vintage&lt;/groupId&gt;
                  &lt;artifactId&gt;junit-vintage-engine&lt;/artifactId&gt;
              &lt;/exclusion&gt;
          &lt;/exclusions&gt;
      &lt;/dependency&gt;
  &lt;/dependencies&gt;
  
  &lt;build&gt;
      &lt;plugins&gt;
          &lt;plugin&gt;
              &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
              &lt;artifactId&gt;spring-boot-maven-plugin&lt;/artifactId&gt;
          &lt;/plugin&gt;
          &lt;plugin&gt;
              &lt;groupId&gt;org.apache.maven.plugins&lt;/groupId&gt;
              &lt;artifactId&gt;maven-compiler-plugin&lt;/artifactId&gt;
              &lt;version&gt;${maven-compiler-plugin.version}&lt;/version&gt;
              &lt;configuration&gt;
                  &lt;source&gt;11&lt;/source&gt;
                  &lt;target&gt;11&lt;/target&gt;
                  &lt;annotationProcessorPaths&gt;
                      &lt;path&gt;
                          &lt;groupId&gt;org.mapstruct&lt;/groupId&gt;
                          &lt;artifactId&gt;mapstruct-processor&lt;/artifactId&gt;
                          &lt;version&gt;${mapstruct.version}&lt;/version&gt;
                      &lt;/path&gt;
                      &lt;annotationProcessorPath&gt;
                          &lt;groupId&gt;org.projectlombok&lt;/groupId&gt;
                          &lt;artifactId&gt;lombok&lt;/artifactId&gt;
                          &lt;version&gt;${lombok.version}&lt;/version&gt;
                      &lt;/annotationProcessorPath&gt;
                  &lt;/annotationProcessorPaths&gt;
              &lt;/configuration&gt;
          &lt;/plugin&gt;
      &lt;/plugins&gt;
  &lt;/build&gt;
  </code></pre>
  
  <p>This my 2 objects to map one to other:
  1st one:</p>
  <pre><code> import lombok.AllArgsConstructor;
   import lombok.Builder;
   import lombok.Data;
   import lombok.NoArgsConstructor;
  
  @Data
  @Builder
  @AllArgsConstructor
  @NoArgsConstructor
  @SuppressWarnings(&quot;unused&quot;)
  public class User {
  
      private Integer id;
  
      private String usrLogin;
  
      private String pass;
  
      private String name;
  
      private String surname;
  
      private Boolean enabled;
  
  }
  </code></pre>
  <p>2nd one:</p>
  <pre><code>import lombok.AllArgsConstructor;
  import lombok.Builder;
  import lombok.Data;
  import lombok.NoArgsConstructor;
  
  @Data
  @Builder
  @AllArgsConstructor
  @NoArgsConstructor
  @SuppressWarnings(&quot;unused&quot;)
  public class UserRequest {
  
      private Integer id;
  
      private String usrLogin;
  
      private String pass;
  
      private String name;
  
      private String surname;
  
      private Boolean enabled;
  
  }
  </code></pre>
  <p>My Mapper inteface:</p>
  <pre><code>import com.domotichouse.app.SpringDomoticHouse.application.dto.User;
  import com.domotichouse.app.SpringDomoticHouse.rest.dto.UserRequest;
  import org.mapstruct.Mapper;
  import org.mapstruct.factory.Mappers;
  
  
  @Mapper
  public interface UserRestMapper {
      
      UserRestMapper MAPPER = Mappers.getMapper(UserRestMapper.class);
      
      User toAplication(UserRequest request);
      
  }
  </code></pre>
  <p>And here is how the anotation implements the interface:</p>
  <pre><code>import com.domotichouse.app.SpringDomoticHouse.application.dto.User;
  import com.domotichouse.app.SpringDomoticHouse.rest.dto.UserRequest;
  
  public class UserRestMapperImpl implements UserRestMapper {
      public UserRestMapperImpl() {
      }
  
      public User toAplication(UserRequest request) {
          if (request == null) {
              return null;
          } else {
              User user = new User();
              return user;
          }
      }
  }
  </code></pre>
  <p>As you can see the Mapper dont map anything.
  PD: I have the lombok pluging installed and the @Data and @Builder anotations work as expected</p>