使用 JaCoCo 和 spring-boot-maven-plugin 生成代码覆盖率

在集成测试期间，我使用 spring-boot-maven-plugin 来启动我的 spring 应用程序：

<plugin>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-maven-plugin</artifactId>
    <executions>
         <execution>
             <id>start-spring-boot</id>
             <phase>pre-integration-test</phase>
             <goals>
                 <goal>start</goal>
             </goals>
         </execution>
         <execution>
             <id>stop-spring-boot</id>
             <phase>post-integration-test</phase>
             <goals>
                 <goal>stop</goal>
             </goals>
         </execution>
     </executions>
</plugin>

现在我想将 JaCoCo 代理添加到执行中，但将其作为代理或 jvmarguments 添加到配置中不起作用。开始时我总是看到：

[INFO] --- spring-boot-maven-plugin:2.2.4.RELEASE:start (start-spring-boot) @ tosca-ui ---
[INFO] Attaching agents: []

如何将 JaCoCo 与 spring-boot-maven-plugin 一起使用？

默认情况下，Spring Boot Maven 插件会创建一个分支，并且必须显式指定代理配置。可以通过设置来完成<agents><agent>...</agent></agents>Spring Boot Maven 插件中的配置属性，但它不适用于 Jacoco，因为没有惯用的方法来找出代理 jar 文件的确切路径。

相反，你可以通过argLineJacoco 设置为 Spring Boot Maven 插件 JVM 参数的变量：

<plugin>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-maven-plugin</artifactId>
    <configuration>
        <jvmArguments>${argLine}</jvmArguments>
    </configuration>
    <executions>
        <execution>
            <id>start-spring-boot</id>
            <phase>pre-integration-test</phase>
            <goals>
                <goal>start</goal>
            </goals>
        </execution>
        <execution>
            <id>stop-spring-boot</id>
            <phase>post-integration-test</phase>
            <goals>
                <goal>stop</goal>
            </goals>
        </execution>
    </executions>
</plugin>

由于必须配置相当多的 Maven 插件才能使其工作，为了避免任何混淆，这里是完整的pom.xml file:

    <?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>2.2.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>jacoco-spring-boot-maven</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>jacoco-spring-boot-maven</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>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <jvmArguments>${argLine}</jvmArguments>
                </configuration>
                <executions>
                    <execution>
                        <id>start-spring-boot</id>
                        <phase>pre-integration-test</phase>
                        <goals>
                            <goal>start</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>stop-spring-boot</id>
                        <phase>post-integration-test</phase>
                        <goals>
                            <goal>stop</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-failsafe-plugin</artifactId>
                <version>3.0.0-M4</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>integration-test</goal>
                            <goal>verify</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.jacoco</groupId>
                <artifactId>jacoco-maven-plugin</artifactId>
                <version>0.8.5</version>
                <executions>
                    <execution>
                        <id>default-prepare-agent</id>
                        <goals>
                            <goal>prepare-agent</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>default-report</id>
                        <phase>verify</phase>
                        <goals>
                            <goal>report</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

有了这个，一旦你执行mvn clean verify您可以在以下位置找到 Jacoco 报告：target/site/jacoco/index.html.

您可以在以下位置找到完整的示例项目jacoco-spring-boot-maven-插件-样本 https://github.com/maciejwalkowiak/jacoco-spring-boot-maven-plugin-sample.git