java - MapStruct + Lombok 一起无法编译 : unknown property in result type

Question

正在使用的技术堆栈:

Java 8 map 结构:1.2.0.Final Lombok : 1.16.18 IDE:IntelliJ - Lombok 插件已安装

• 最初，当我删除 getter 和 setter 并添加 @Getter 和 @Setter 注释时遇到问题，mapstruct 无法找到属性并显示:结果类型 com.vg.once.dto.OneDto 中存在未知属性“id”。您指的是“null”吗？
• 我发现 Lombok 1.16.14 或更高版本与 MapStruct 1.2.0.Beta1 或更高版本是兼容的并且可以一起工作，但我的版本比所需的版本更新，但问题仍然出现。
• 我已经尝试过的另一个解决方案是运行 Lombok 的 Delombok 插件，但仍然出现了同样的问题。

以下是项目文件:

实体对象:One.java:

import lombok.Getter;
import lombok.Setter;

@Getter
@Setter
public class One {

    private int id;
    private Integer version;
    private int projectId;
    private String title;
    private String code;
    private int sortOrder;

}

DTO 对象:OneDTO.java:

import lombok.Getter;
import lombok.Setter;

@Getter
@Setter
public class OneDto {

    private int id;
    private Integer version;
    private int projectId;
    private String title;
    private String code;
    private int sortOrder;

}

映射器类:OneMapper.java

import org.mapstruct.Mapper;
import org.mapstruct.Mapping;

import com.vg.once.dto.OneDto;
import com.vg.once.entity.One;

@Mapper
public interface OneMapper {

    @Mapping(target="id", source="one.id")
    OneDto createOne (One one);

}

pom.xml

<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">

  <modelVersion>4.0.0</modelVersion>
  <groupId>com.vg</groupId>
  <artifactId>mapstruct</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <name>Mapstruct-test</name>

    <properties>
        <java.version>1.8</java.version>
        <org.mapstruct.version>1.2.0.Final</org.mapstruct.version>
        <org.projectlombok.version>1.16.18</org.projectlombok.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>${org.projectlombok.version}</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct-jdk8</artifactId>
            <version>${org.mapstruct.version}</version>
        </dependency>
    </dependencies>

    <build>
        <plugins> 
         <plugin>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok-maven-plugin</artifactId>
                <version>1.16.18.1</version>
                <executions>
                    <execution>
                        <phase>generate-sources</phase>
                        <goals>
                            <goal>delombok</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <sourceDirectory>src/main/java</sourceDirectory>
                    <addOutputDirectory>false</addOutputDirectory>
                    <outputDirectory>${project.build.directory}/delombok</outputDirectory>
                    <encoding>UTF-8</encoding>
                    <skip>false</skip>
                    <verbose>false</verbose>
                </configuration>
            </plugin>       
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.6.1</version>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                    <annotationProcessorPaths>
                        <path>
                            <groupId>org.mapstruct</groupId>
                            <artifactId>mapstruct-processor</artifactId>
                            <version>${org.mapstruct.version}</version>
                        </path>
                    </annotationProcessorPaths>
                </configuration>
            </plugin>
        </plugins>
    </build>  
</project>

构建跟踪:

[INFO] Scanning for projects...
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building Mapstruct-test 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- lombok-maven-plugin:1.16.18.1:delombok (default) @ mapstruct ---
[INFO] Delombok complete.
[INFO] 
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ mapstruct ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] Copying 0 resource
[INFO] 
[INFO] --- maven-compiler-plugin:3.6.1:compile (default-compile) @ mapstruct ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!
[INFO] Compiling 5 source files to /home/vivekgupta/Documents/workspaces/mapstruct-test/mapstruct/target/classes
[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR : 
[INFO] -------------------------------------------------------------
[ERROR] /home/vivekgupta/Documents/workspaces/mapstruct-test/mapstruct/src/main/java/com/vg/once/mapper/OneMapper.java:[12,9] Unknown property "id" in result type com.vg.once.dto.OneDto. Did you mean "null"?
[INFO] 1 error
[INFO] -------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.637 s
[INFO] Finished at: 2017-12-06T19:23:53+05:30
[INFO] Final Memory: 19M/235M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.6.1:compile (default-compile) on project mapstruct: Compilation failure
[ERROR] /home/vivekgupta/Documents/workspaces/mapstruct-test/mapstruct/src/main/java/com/vg/once/mapper/OneMapper.java:[12,9] Unknown property "id" in result type com.vg.once.dto.OneDto. Did you mean "null"?
[ERROR] -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException

请分享我如何同时使用 Lombok 和 MapStruct 来实现此功能？

Answer 1

它不起作用的原因是Maven只使用MapStruct处理器而不是Lombok处理器。 annotationProcessorPaths 告诉 Maven 应该使用哪些处理器。

delombok 不执行任何操作，因为每个类最终都会有 2 个文件，而且我认为 Maven 编译器看不到它们。

您有 2 个选择:

选项 1:在 annotationProcessorPaths 中添加 lombok 依赖项

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.6.1</version>
    <configuration>
        <source>${java.version}</source>
        <target>${java.version}</target>
        <annotationProcessorPaths>
            <path>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <version>${org.projectlombok.version}</version>
            </path>
            <!-- This is needed when using Lombok 1.18.16 and above -->
            <path>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok-mapstruct-binding</artifactId>
                <version>0.2.0</version>
            </path>
            <!-- Mapstruct should follow the lombok path(s) -->
            <path>
                <groupId>org.mapstruct</groupId>
                <artifactId>mapstruct-processor</artifactId>
                <version>${org.mapstruct.version}</version>
            </path>
        </annotationProcessorPaths>
    </configuration>
</plugin>

选项 2:

将 mapstruct-processor 依赖项添加到您的依赖项中，并删除 annotationProcessorPaths。这样，maven 编译器将获取依赖项中的所有注释处理器。

我建议使用选项 1，这样您就可以确定您没有在代码中使用某些 MapStruct 传递依赖项和内部类。

编辑:

为了确保 IntelliJ 注释处理也正常工作，您必须将 mapstruct-processor 添加为 provided 依赖项，因为 IDEA-150621 。 IntelliJ 目前不使用 Maven 中的 annotationProcessorPaths 来正确配置项目。

编辑2:

添加有关 Lombok 1.18.16 所需的 lombok-mapstruct-binding 的信息和注释。