Eclipse 2021-06（4.20.0）基于Java 17 JRE启动报错的解决方法咨询

问题根源 #

你遇到的java.lang.reflect.InaccessibleObjectException是Java 9+模块系统（JPMS）的访问限制导致的：Java 17收紧了内部API的访问权限，而Eclipse 2021-06（4.20.0）本身只官方支持Java 11~16，同时你的Checkstyle插件版本也未适配Java 17的模块规则，两者试图访问java.base模块中受保护的内部成员，但模块并未开放给未命名模块（unnamed module）。

具体解决方案（按推荐优先级排序） #

1. 降级JRE到Eclipse官方支持的版本

这是最稳妥的解决方式，Eclipse 4.20官方推荐使用Java 11或Java 16：

• 下载并安装Java 11/16 JRE/JDK
• 修改Eclipse安装目录下的eclipse.ini，在-vmargs之前添加JVM路径（注意参数要单独占行）：

  -vm
  C:\Program Files\Java\jdk-11.0.16\bin\javaw.exe
  

  （macOS/Linux路径类似，比如/Library/Java/JavaVirtualMachines/jdk-11.jdk/Contents/Home/bin/java）

2. 升级Eclipse到支持Java 17的版本

Eclipse从2021-09（4.21）开始正式支持Java 17，升级到新版本（如2023-09或更高）可以原生适配Java 17，无需额外参数：

• 直接在Eclipse中通过Help > Check for Updates升级，或下载最新版本重新安装
• 同时建议升级Checkstyle插件到8.49+版本，彻底解决插件的模块访问问题

3. 临时添加VM参数强制开放模块（不推荐长期使用）

如果必须使用Java 17和旧版Eclipse，可以在eclipse.ini的-vmargs部分添加以下参数，强制开放java.base模块的内部API给未命名模块：

--add-opens java.base/java.lang=ALL-UNNAMED
--add-opens java.base/java.net=ALL-UNNAMED

⚠️ 注意：这只是临时 workaround，可能会引入其他兼容性问题，官方不推荐长期使用。

4. 调整Checkstyle插件

第三个错误是Checkstyle插件导致的，你可以：

• 升级Checkstyle插件到支持Java 17的版本（在Eclipse Marketplace中搜索Checkstyle并更新）
• 如果暂时不需要Checkstyle，通过Window > Show View > Other > Plug-ins找到Checkstyle相关插件，右键选择Disable临时禁用

报错堆栈信息 #

java.lang.reflect.InaccessibleObjectException: Unable to make protected final java.lang.Class java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int) throws java.lang.ClassFormatError accessible: module java.base does not "opens java.lang" to unnamed module @2bc378f7
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354)
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297)
at java.base/java.lang.reflect.Method.checkCanSetAccessible(Method.java:199)
at java.base/java.lang.reflect.Method.setAccessible(Method.java:193)
at org.eclipse.osgi.internal.loader.ModuleClassLoader.overrideLoadResult(ModuleClassLoader.java:86)
at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
at org.eclipse.jdt.internal.compiler.parser.Parser.endParse(Parser.java:11750)
at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:12949)
at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:13176)
at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:13133)
at org.eclipse.jdt.internal.compiler.parser.Parser.dietParse(Parser.java:11521)
at org.eclipse.jdt.internal.compiler.Compiler.internalBeginToCompile(Compiler.java:850)
at org.eclipse.jdt.internal.compiler.Compiler.beginToCompile(Compiler.java:394)
at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:444)
at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:426)
at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:377)
at org.eclipse.jdt.internal.core.builder.BatchImageBuilder.compile(BatchImageBuilder.java:214)
at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:309)
at org.eclipse.jdt.internal.core.builder.BatchImageBuilder.build(BatchImageBuilder.java:79)
at org.eclipse.jdt.internal.core.builder.JavaBuilder.buildAll(JavaBuilder.java:272)
at org.eclipse.jdt.internal.core.builder.JavaBuilder.build(JavaBuilder.java:192)
at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:846)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:229)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:277)
at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:330)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:333)
at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:385)
at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:406)
at org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:154)
at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:244)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)

java.lang.reflect.InaccessibleObjectException: Unable to make protected final java.lang.Class java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int) throws java.lang.ClassFormatError accessible: module java.base does not "opens java.lang" to unnamed module @2bc378f7
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354)
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297)
at java.base/java.lang.reflect.Method.checkCanSetAccessible(Method.java:199)
at java.base/java.lang.reflect.Method.setAccessible(Method.java:193)
at org.eclipse.osgi.internal.loader.ModuleClassLoader.overrideLoadResult(ModuleClassLoader.java:86)
at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
at org.eclipse.jdt.internal.compiler.parser.Parser.endParse(Parser.java:11750)
at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:12949)
at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:13176)
at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:13133)
at org.eclipse.jdt.internal.compiler.parser.Parser.dietParse(Parser.java:11521)
at org.eclipse.jdt.internal.compiler.Compiler.internalBeginToCompile(Compiler.java:850)
at org.eclipse.jdt.internal.compiler.Compiler.beginToCompile(Compiler.java:394)
at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:444)
at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:426)
at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:377)
at org.eclipse.jdt.internal.core.builder.BatchImageBuilder.compile(BatchImageBuilder.java:214)
at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:309)
at org.eclipse.jdt.internal.core.builder.BatchImageBuilder.build(BatchImageBuilder.java:79)
at org.eclipse.jdt.internal.core.builder.JavaBuilder.buildAll(JavaBuilder.java:272)
at org.eclipse.jdt.internal.core.builder.JavaBuilder.build(JavaBuilder.java:187)
at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:846)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:229)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:277)
at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:330)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:333)
at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:385)
at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:406)
at org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:154)
at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:244)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)

java.lang.reflect.InaccessibleObjectException: Unable to make field private static volatile java.net.Authenticator java.net.Authenticator.theAuthenticator accessible: module java.base does not "opens java.net" to unnamed module @1ab8b487
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354)
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297)
at java.base/java.lang.reflect.Field.checkCanSetAccessible(Field.java:178)
at java.base/java.lang.reflect.Field.setAccessible(Field.java:172)
at net.sf.eclipsecs.core.config.configtypes.RemoteConfigurationType$RemoteConfigAuthenticator.getDefault(RemoteConfigurationType.java:376)
at net.sf.eclipsecs.core.config.configtypes.RemoteConfigurationType.getCheckstyleConfiguration(RemoteConfigurationType.java:99)
at net.sf.eclipsecs.core.config.CheckConfiguration.getCheckstyleConfiguration(CheckConfiguration.java:161)
at net.sf.eclipsecs.core.builder.CheckerFactory.getCacheKey(CheckerFactory.java:157)
at net.sf.eclipsecs.core.builder.CheckerFactory.createChecker(CheckerFactory.java:99)
at net.sf.eclipsecs.core.builder.Auditor.runAudit(Auditor.java:139)
at net.sf.eclipsecs.core.builder.CheckstyleBuilder.handleBuildSelection(CheckstyleBuilder.java:307)
at net.sf.eclipsecs.core.builder.CheckstyleBuilder.build(CheckstyleBuilder.java:173)
at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:846)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:229)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:277)
at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:330)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:333)
at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:385)
at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:406)
at org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:154)
at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:244)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)

内容的提问来源于stack exchange，提问作者Lii