Gradle依赖锁定报错：相关技术术语含义解析求助

报错场景 #

升级Gradle插件后执行resolveAndLockAll --write-locks更新依赖锁定文件时，出现如下错误：

Execution failed for task ':resolveAndLockAll'.
> Could not resolve all files for configuration ':allCodeCoverageReportSourceDirectories'.
   > Could not resolve com.google.protobuf:protobuf-java:3.15.7.
     Required by:
         project : > project :my-project
      > No matching variant of com.google.protobuf:protobuf-java:3.21.4 was found. The consumer was configured to find a component of category 'verification', and its dependencies declared externally, as well as attribute 'org.gradle.verificationtype' with value 'main-sources' but:
          - Variant 'compile' capability com.google.protobuf:protobuf-java:3.21.4:
              - Incompatible because this component declares a library and the consumer needed a component of category 'verification'
              - Other compatible attributes:
                  - Doesn't say anything about how its dependencies are found (required its dependencies declared externally)
                  - Doesn't say anything about org.gradle.verificationtype (required 'main-sources')
          - Variant 'enforced-platform-compile' capability com.google.protobuf:protobuf-java-derived-enforced-platform:3.21.4:
              - Incompatible because this component declares an enforced platform and the consumer needed a component of category 'verification'
              - Other compatible attributes:
                  - Doesn't say anything about how its dependencies are found (required its dependencies declared externally)
                  - Doesn't say anything about org.gradle.verificationtype (required 'main-sources')
...
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术语定义（对应提问中的术语） #

• Variant capability：Gradle中每个依赖组件会包含多个功能变体（如编译时、运行时变体），每个变体的capability是它的核心身份标识，用来明确该变体的类型与用途。比如报错里的compile变体capability为com.google.protobuf:protobuf-java:3.21.4，说明这是一个供编译使用的普通Java库；enforced-platform-compile变体的capability是com.google.protobuf:protobuf-java-derived-enforced-platform:3.21.4，则表明这是一个强制版本的平台变体。
• Compatible variant capability：指依赖变体的capability与消费者的需求完全匹配的情况。在本次错误中，消费者需要的是verification类别的组件，但所有protobuf-java的变体capability都属于普通库或强制平台，没有符合要求的，因此不存在兼容的variant capability。
• Compatible attribute：Gradle通过属性来定义变体的特性，兼容属性就是指依赖变体的属性符合消费者配置要求的部分。比如报错里消费者要求org.gradle.verificationtype属性值为main-sources，但所有变体都未声明该属性，所以这部分不兼容；若某个变体的属性正好满足消费者的要求，那就是兼容属性。
• Enforced platform：一种特殊的依赖管理组件，它会强制项目中所有相关依赖使用它指定的版本，直接覆盖其他地方的版本声明。报错里的enforced-platform-compile变体就是这种类型，作用是统一protobuf相关依赖的版本。
• Consumer：这里指当前项目中发起依赖请求的主体，也就是:allCodeCoverageReportSourceDirectories这个配置项，它在解析依赖时会设定自身的需求（比如需要verification类别的组件、外部声明的依赖等）。
• Component of category 'verification'：属于verification类别的组件，这类组件专门用于代码验证、覆盖率报告等工具场景，而非普通的业务代码库。本次报错中，protobuf-java是普通业务库，不符合该类别要求，因此无法匹配。
• Dependencies declared externally：指依赖是从外部仓库（如Maven Central、私有仓库）获取的，而非项目内部模块或本地文件。消费者要求依赖必须是外部声明的，但报错中的变体未明确标识这一点，因此不满足需求。

内容的提问来源于stack exchange，提问作者Toldry