AWS SAM构建Spring Boot 3应用失败：checkstyle插件配置解析错误

问题现象 #

执行aws sam build构建基于JDK 21的Spring Boot 3应用时，抛出以下错误：

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-checkstyle-plugin:3.3.1:check (default) on project xxxxx: Unable to parse configuration of mojo org.apache.maven.plugins:maven-checkstyle-plugin:3.3.1:check: Basic element 'includes' must not contain child elements -> [Help 1]

直接执行mvn clean package可正常完成构建，注释maven-pmd-plugin和maven-checkstyle-plugin的配置后，SAM Build也能运行，但需要保留代码检查功能。

问题原因 #

你使用的maven-checkstyle-plugin:3.3.1版本中，<includes>参数要求配置为逗号分隔的字符串，而非嵌套的<include>子元素列表。虽然直接mvn命令兼容这种写法，但AWS SAM Build的Maven执行环境对配置格式解析更严格，因此触发错误。

解决方案 #

方案1：修改includes配置为字符串形式 #

将两个插件中的<includes>块替换为单个字符串值：

修改后的PMD插件配置：

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-pmd-plugin</artifactId>
  <version>3.22.0</version>
  <configuration>
    <targetJdk>21</targetJdk>
    <encoding>UTF-8</encoding>
    <consoleOutput>true</consoleOutput>
    <failOnViolation>false</failOnViolation>
    <printFailingErrors>true</printFailingErrors>
    <linkXRef>false</linkXRef>
    <includes>**/*.java</includes>
  </configuration>
  <executions>
    <execution>
      <goals>
        <goal>check</goal>
        <goal>cpd-check</goal>
      </goals>
    </execution>
  </executions>
</plugin>

修改后的Checkstyle插件配置：

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-checkstyle-plugin</artifactId>
  <version>3.3.1</version>
  <configuration>
    <configLocation>checkstyle.xml</configLocation>
    <encoding>UTF-8</encoding>
    <consoleOutput>true</consoleOutput>
    <failOnViolation>true</failOnViolation>
    <violationSeverity>warning</violationSeverity>
    <linkXRef>false</linkXRef>
    <includes>**/*.java</includes>
  </configuration>
  <executions>
    <execution>
      <goals>
        <goal>check</goal>
      </goals>
    </execution>
  </executions>
</plugin>

方案2：升级Checkstyle插件版本 #

较新的maven-checkstyle-plugin版本（如3.4.0及以上）支持使用<include>子元素列表配置includes，升级后可保留原有嵌套格式：

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-checkstyle-plugin</artifactId>
  <version>3.4.0</version>
  <configuration>
    <configLocation>checkstyle.xml</configLocation>
    <encoding>UTF-8</encoding>
    <consoleOutput>true</consoleOutput>
    <failOnViolation>true</failOnViolation>
    <violationSeverity>warning</violationSeverity>
    <linkXRef>false</linkXRef>
    <includes>
      <include>**/*.java</include>
    </includes>
  </configuration>
  <executions>
    <execution>
      <goals>
        <goal>check</goal>
      </goals>
    </execution>
  </executions>
</plugin>

两种方案均可解决SAM Build的配置解析错误，同时保留PMD和Checkstyle的代码检查功能。

内容的提问来源于stack exchange，提问作者Anoop Varma