Maven项目Log4j2转换符未识别错误求助（已尝试常规方案）

在Maven项目中遇到了与帖子《log4j2 ERROR StatusLogger Unrecognized conversion specifier》描述一致的问题，但已经尝试了帖子中的两种解决方案——排除Log4j2Plugins.dat文件、使用Log4j的清单转换器插件，问题仍未解决。此外已确认生成的Jar文件中，无论META-INF目录还是其他结构下，均不存在Log4j2Plugins.dat文件。

错误日志 #

2024-06-22T00:41:49.937Z main ERROR Unrecognized format specifier [d]                                                     
2024-06-22T00:41:49.952Z main ERROR Unrecognized conversion specifier [d] starting at position 16 in conversion pattern.
2024-06-22T00:41:49.953Z main ERROR Unrecognized format specifier [thread]                                              
2024-06-22T00:41:49.953Z main ERROR Unrecognized conversion specifier [thread] starting at position 25 in conversion pattern.
2024-06-22T00:41:49.954Z main ERROR Unrecognized format specifier [level]                                              
2024-06-22T00:41:49.954Z main ERROR Unrecognized conversion specifier [level] starting at position 35 in conversion pattern.
2024-06-22T00:41:49.954Z main ERROR Unrecognized format specifier [logger]                                              
2024-06-22T00:41:49.954Z main ERROR Unrecognized conversion specifier [logger] starting at position 47 in conversion pattern.
2024-06-22T00:41:49.955Z main ERROR Unrecognized format specifier [msg]                                                 
2024-06-22T00:41:49.955Z main ERROR Unrecognized conversion specifier [msg] starting at position 54 in conversion pattern.
2024-06-22T00:41:49.955Z main ERROR Unrecognized format specifier [n]                                                   
2024-06-22T00:41:49.956Z main ERROR Unrecognized conversion specifier [n] starting at position 56 in conversion pattern.
2024-06-22T00:41:49.964Z main ERROR Unrecognized format specifier [d]                                                   
2024-06-22T00:41:49.964Z main ERROR Unrecognized conversion specifier [d] starting at position 16 in conversion pattern.
2024-06-22T00:41:49.964Z main ERROR Unrecognized format specifier [thread]    
2024-06-22T00:41:49.965Z main ERROR Unrecognized conversion specifier [thread] starting at position 25 in conversion pattern.
2024-06-22T00:41:49.965Z main ERROR Unrecognized format specifier [level]                 
2024-06-22T00:41:49.965Z main ERROR Unrecognized conversion specifier [level] starting at position 35 in conversion pattern.
2024-06-22T00:41:49.965Z main ERROR Unrecognized format specifier [logger]
2024-06-22T00:41:49.965Z main ERROR Unrecognized conversion specifier [logger] starting at position 47 in conversion pattern.
2024-06-22T00:41:49.965Z main ERROR Unrecognized format specifier [msg]                                
2024-06-22T00:41:49.965Z main ERROR Unrecognized conversion specifier [msg] starting at position 54 in conversion pattern.
2024-06-22T00:41:49.965Z main ERROR Unrecognized format specifier [n]             
2024-06-22T00:41:49.966Z main ERROR Unrecognized conversion specifier [n] starting at position 56 in conversion pattern.
2024-06-22T00:41:51.876Z main ERROR Unrecognized format specifier [p]
2024-06-22T00:41:51.876Z main ERROR Unrecognized conversion specifier [p] starting at position 4 in conversion pattern.
2024-06-22T00:41:51.877Z main ERROR Unrecognized format specifier [d]
2024-06-22T00:41:51.877Z main ERROR Unrecognized conversion specifier [d] starting at position 21 in conversion pattern.
2024-06-22T00:41:51.877Z main ERROR Unrecognized format specifier [C]                                 
2024-06-22T00:41:51.877Z main ERROR Unrecognized conversion specifier [C] starting at position 27 in conversion pattern.                        
2024-06-22T00:41:51.877Z main ERROR Unrecognized format specifier [m]
2024-06-22T00:41:51.877Z main ERROR Unrecognized conversion specifier [m] starting at position 32 in conversion pattern.
2024-06-22T00:41:51.877Z main ERROR Unrecognized format specifier [n]
2024-06-22T00:41:51.877Z main ERROR Unrecognized conversion specifier [n] starting at position 35 in conversion pattern.

相关Maven pom片段 #

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-shade-plugin</artifactId>
  <dependencies>
    <dependency>
      <groupId>org.apache.logging.log4j</groupId>
      <artifactId>log4j-transform-maven-shade-plugin-extensions</artifactId>
      <version>0.1.0</version>
    </dependency>
  </dependencies>
  <executions>
    <execution>
      <id>package-jar</id>
      <goals>
        <goal>shade</goal>
      </goals>
      <phase>package</phase>
      <configuration>
        <minimizeJar>true</minimizeJar>
        <createDependencyReducedPom>false</createDependencyReducedPom>
        <artifactSet>
          <excludes>
            <exclude>org.broadinstitute.gatk:gsalib:tar.gz:*</exclude>
            <exclude>org.broadinstitute.gatk:*:tar.bz2:example-resources</exclude>
          </excludes>
        </artifactSet>
        <filters>
          <filter>
            <artifact>*:*</artifact>
            <excludes>
              <exclude>META-INF/services/javax.annotation.processing.Processor</exclude>
              <exclude>**/Log4j2Plugins.dat</exclude>
            </excludes>
          </filter>
        </filters>
        <transformers>
          <transformer implementation="org.apache.logging.log4j.maven.plugins.shade.transformer.Log4j2PluginCacheFileTransformer"/>
          <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
            <manifestEntries>
              <Multi-Release>true</Multi-Release>
              <Main-Class>${app.main.class}</Main-Class>
            </manifestEntries>
          </transformer>
          <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
            <resource>${resource.bundle.path}</resource>
          </transformer>
        </transformers>
      </configuration>
    </execution>
  </executions>
</plugin>

排查建议 #

• 关闭Jar最小化：当前启用了<minimizeJar>true</minimizeJar>，该配置会自动移除未被检测到引用的类，很可能误删了Log4j2格式转换相关的核心组件。先将其设为false，重新打包运行，观察错误是否消失。
• 检查Log4j2依赖完整性：确认pom中已完整引入log4j-core和log4j-api，且版本一致。用mvn dependency:tree查看依赖树，排查是否有其他依赖引入了不兼容的Log4j2版本。
• 验证Log4j2配置文件：检查你的log4j2配置文件（如log4j2.xml）中的转换模式语法是否正确，比如是否将%d误写为[d]；同时确认配置文件是否被正确加载到Jar包中。
• 更新Log4j转换器插件版本：当前使用的log4j-transform-maven-shade-plugin-extensions版本为0.1.0，属于早期版本，尝试升级至最新稳定版（如0.2.0），修复可能存在的Shade兼容问题。
• 调整Transformer执行顺序：确保Log4j2PluginCacheFileTransformer在所有Transformer中优先执行，避免后续转换操作破坏Log4j2插件缓存的生成。

内容的提问来源于stack exchange，提问作者Valentin Ruano