使用高版本JDK编译低版本代码
背景
SonarQube运行于Java17，使用Sonar的Maven插件编译时，如果编译使用的JDK版本低于SonarQube使用的Java17，则会提示Java文件不匹配问题。
Error during SonarScanner execution
java.lang.UnsupportedClassVersionError: org/sonar/batch/bootstrapper/EnvironmentInformation has been compiled by a more recent version of the Java Runtime (class file version 61.0), this version of the Java Runtime only recognizes class file versions up to 52.0
maven-compiler-plugin
通过设置编译插件配置来输出指定版本的编译。
<plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-compiler-plugin</artifactId><version>3.8.1</version><configuration><fork>true</fork><source>1.8</source><compilerVersion>1.8</compilerVersion><target>1.8</target><encoding>UTF-8</encoding></configuration>
</plugin>
当缺少上面的configuration配置时，可能出现编译报错。
Fatal error compiling: java.lang.ExceptionInInitializerError: Unable to make field private com.sun.tools.javac.processing.JavacProcessingEnvironment$DiscoveredProcessors com.sun.tools.javac.processing.JavacProcessingEnvironment.discoveredProcs accessible: module jdk.compiler does not “opens com.sun.tools.javac.processing” to unnamed module
JDK对应的Class File版本信息
| JDK版本 | Class File版本 |
|---|---|
| 1.0.2 | 45 |
| 1.1 | 45 |
| 1.2 | 46 |
| 1.3 | 47 |
| 1.4 | 48 |
| 5.0 | 49 |
| 6 | 50 |
| 7 | 51 |
| 8 | 52 |
| 9 | 53 |
| 10 | 54 |
| 11 | 55 |
| 12 | 56 |
| 13 | 57 |
| 14 | 58 |
| 15 | 59 |
| 16 | 60 |
| 17 | 61 |
| 18 | 62 |
| 19 | 63 |
| 20 | 64 |
| 21 | 65 |