In my multi-module project I have a code and tests in separate modules. When I run maven command 'mvn clean install -DskipTests=false', jacoco.exec file is generated in test module but Jacoco complains about missing classes directory. In jacoco-report module, the report is generated but its empty.

在我的多模块项目中，我将代码和测试放在不同的模块中。当我运行maven命令‘MVN CLEAN INSTALL-DskipTest=FALSE’时，在测试模块中生成了Jacoco.exec文件，但Jacoco报告缺少CLASS目录。在Jacoco-Report模块中，报告是生成的，但它是空的。

How can I configure it to generate report or to be more specific how can I point Jacoco to the classes directory?

我如何配置它以生成报告，或者更具体地说，我如何将Jacoco指向CLASS目录？

Here is structure of my project:

以下是我的项目的结构：

My pom file from 'multi-module':

我的POM文件来自‘多模块’：

 <build>
        <finalName>${project.artifactId}-${project.version}</finalName>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <release>11</release>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <version>3.0.0-M3</version>
                <configuration>
                    <argLine>
                        --illegal-access=permit
                    </argLine>
                    <argLine>@{argLine}</argLine>
                    <trimStackTrace>false</trimStackTrace>
                    <skipTests>${skipTests}</skipTests>
                    <testFailureIgnore>true</testFailureIgnore>
                    <includes>
                        <include>**/*Test.java</include>
                    </includes>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-release-plugin</artifactId>
                <version>2.5.3</version>
            </plugin>
            <plugin>
                <groupId>org.jacoco</groupId>
                <artifactId>jacoco-maven-plugin</artifactId>
                <version>0.8.10</version>
                <configuration>
                    <destFile>${project.basedir}/../multi-module-core/target/jacoco.exec</destFile>
                </configuration>
                <executions>
                    <execution>
                        <id>prepare-agent</id>
                        <goals>
                            <goal>prepare-agent</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>jacoco-site</id>
                        <goals>
                            <goal>report</goal>
                        </goals>
                        <configuration>
                            <dataFile>${project.basedir}/../multi-module-tests/target/jacoco.exec</dataFile>
                            <includes>
                                <include>${project.basedir}/../multi-module-core/target/classes/**</include>
                            </includes>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>`

Pom file from 'multi-module-core':

来自‘多模块核心’的POM文件：

    <build>
        <finalName>${project.artifactId}-${project.version}</finalName>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <release>11</release>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>3.2.3</version>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-release-plugin</artifactId>
                <version>2.5.3</version>
            </plugin>
        </plugins>
    </build>

Pom file from 'multi-module-tests':

多模块测试中的POM文件：

   <build>
        <finalName>${project.artifactId}-${project.version}</finalName>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <release>11</release>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-surefire-plugin</artifactId>
                <version>2.18</version>
                <configuration>
                    <argLine>@{argLine}</argLine>
                    <skipTests>${skipTests}</skipTests>
                    <testFailureIgnore>true</testFailureIgnore>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-clean-plugin</artifactId>
                <version>2.5</version>
                <configuration>
                    <filesets>
                        <fileset>
                            <directory>.</directory>
                            <includes>
                                <include>**/*.log</include>
                            </includes>
                            <followSymlinks>false</followSymlinks>
                        </fileset>
                    </filesets>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-release-plugin</artifactId>
                <version>2.5.3</version>
            </plugin>
        </plugins>
    </build>

Pom file from 'jacoco-report':

来自‘Jacoco-Report’的POM文件：

  <build>
        <plugins>
            <plugin>
                <groupId>org.jacoco</groupId>
                <artifactId>jacoco-maven-plugin</artifactId>
                <version>0.8.10</version>
                <executions>
                    <execution>
                        <id>report-aggregate</id>
                        <phase>verify</phase>
                        <goals>
                            <goal>report-aggregate</goal>
                        </goals>
                        <configuration>
                            <dataFileIncludes>
                                <dataFileInclude>**/jacoco.exec</dataFileInclude>
                            </dataFileIncludes>
                            <outputDirectory>
                                ${project.reporting.outputDirectory}/jacoco-aggregate
                            </outputDirectory>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

So far I tried multiple configurations from all over the internet but with the same result. Appreciate any help or suggestions.

到目前为止，我从互联网上尝试了多种配置，但结果都是一样的。感谢任何帮助或建议。

EDIT 1:
As suggested I run mvn command in debug mode:

编辑1：按照建议，我在调试模式下运行MVN命令：

mvn clean verify -DskipTests=false -X

IT turns out that the following path is wrong:

事实证明，以下路径是错误的：

<include>${project.basedir}/../multi-module-core/target/classes/**</include>

and it points to : [C:\Projects\jococo\test\multi-module\multi-module-tests/../multi-module-core/target/classes/]** .

它指向：[C：\Projects\jococo\test\multi-module\multi-module-tests/../multi-module-core/target/classes/]**。

But even when I hard coded the path to C:\Projects\jococo\test\multi-module\multi-module-core\target\classes

但即使我硬编码了通往C：\Projects\jococo\test\multi-module\multi-module-core\target\classes的路径

Here is what I got during jacoco:report phase:

以下是我在Jacoco：报告阶段得到的信息：

 includes = [C:\Projects\jococo\test\multi-module\multi-module-core\target\classes]

It looks like the paths pointing to the correct directory with classes but I still got the same error message: Skipping JaCoCo execution due to missing classes directory.

它看起来像是指向包含类的正确目录的路径，但我仍然收到相同的错误消息：由于缺少类目录，正在跳过JaCoCo执行。

EDIT 2:

编辑2：

For the reference here is GitHub repo to the project: https://github.com/KonarzewskiP/jacoco-multi-module

此处引用的是GitHub对该项目的回购：https://github.com/KonarzewskiP/jacoco-multi-module

There are many reasons for the problem, but consider this step to find out the configuration missing section.

出现此问题的原因有很多，但请考虑此步骤以找出配置缺少的部分。

1. Check Data File Location:
   In your multi-module-tests module's pom.xml, ensure that the jacoco.exec file is being generated in the correct location. The destFile property should specify the full path to where the jacoco.exec file should be saved, which is typically within the target directory of the module.

   
   

   <configuration>
       <destFile>${project.build.directory}/jacoco.exec</destFile>
   </configuration>
   

   
   



2. Check Include Patterns:
   In the jacoco-report module's pom.xml, your <dataFileIncludes> pattern should match the location of jacoco.exec files from all your modules. Make sure it's set correctly to include all the modules.

   
   

   <dataFileIncludes>
       <dataFileInclude>/target/jacoco.exec</dataFileInclude>
   </dataFileIncludes>
   

   
   



3. Ensure Correct Execution Order:
   When running mvn clean install -DskipTests=false, make sure that the modules are executed in the correct order. Dependencies between modules must be resolved in the right sequence to ensure that coverage data is collected properly.

   
   



4. Run verify Phase:
   Ensure that you run the verify phase to generate the reports in the jacoco-report module, as specified in your jacoco-report module's pom.xml.

   
   

   mvn clean verify

   
   



5. Verify Relative Paths:
   Double-check that relative paths are correctly configured in your POM files, especially for properties like destFile. Relative paths should be based on the current module's location.

   
   



6. Plugin Versions Compatibility:
   Verify that you are using compatible versions of Maven, JaCoCo, and related plugins. Incompatibilities can lead to issues with report generation.

   
   



7. Debugging Output:
   Enable debugging output (-X flag) when running Maven (mvn clean install -DskipTests=false -X) to get more detailed information about what is happening during the build process. This might help pinpoint the issue.

   
   



8. Check Classpath Configuration:
   Ensure that the classes and test classes directories are correctly configured in your POM files for both the jacoco-maven-plugin and the maven-surefire-plugin. Verify that the includes section in jacoco-maven-plugin covers the classes you want to include in the report.

   
   

After making these adjustments, try running the build again (mvn clean verify) and check if the JaCoCo report is generated correctly in the jacoco-report module with the expected coverage data.

在进行这些调整之后，尝试再次运行构建(MVN CLEAN VERIFY)，并检查JaCoCo报告是否使用预期的覆盖率数据在Jacoco-Report模块中正确生成。

Hope I was helpful.

希望我能帮上忙。