java8: 因为lambda表达写法造成的编译错误: java.lang.AssertionError: isSubClas

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今天在命令行编译的时间遇到了一个以前从来没有遇到的编译错误：

编译器 (1.8.0_401) 中出现异常错误。如果在 Bug Database (http://bugs.java.com) 中没有找到该错误, 请通过 Java Bug 报告页 (http://bugreport.java.com) 建立该 Java 编译器 Bug。请在报告中附上您的程序和以下诊断信息。谢谢。
java.lang.AssertionError: isSubClass DEVICE_T
at com.sun.tools.javac.code.Symbol.isSubClass(Symbol.java:447)
at com.sun.tools.javac.code.Symbol.isMemberOf(Symbol.java:456)
at com.sun.tools.javac.code.Symbol $M e t h o d S y m b o l . o v e r r i d e s (S y m b o l . j a v a : 1479) a t c o m . s u n . t o o l s . j a v a c . c o d e . T y p e s$ ImplementationCache.implementationInternal(Types.java:2693)
at com.sun.tools.javac.code.Types $I m p l e m e n t a t i o n C a c h e . g e t (T y p e s . j a v a : 2675) a t c o m . s u n . t o o l s . j a v a c . c o d e . T y p e s . i m p l e m e n t a t i o n (T y p e s . j a v a : 2704) a t c o m . s u n . t o o l s . j a v a c . c o d e . S y m b o l$ MethodSymbol.implementation(Symbol.java:1539)
at com.sun.tools.javac.code.Symbol $M e t h o d S y m b o l . i m p l e m e n t a t i o n (S y m b o l . j a v a : 1528) a t c o m . s u n . t o o l s . j a v a c . c o m p . R e s o l v e . n o t O v e r r i d d e n I n (R e s o l v e . j a v a : 419) a t c o m . s u n . t o o l s . j a v a c . c o m p . R e s o l v e . i s A c c e s s i b l e (R e s o l v e . j a v a : 405) a t c o m . s u n . t o o l s . j a v a c . c o m p . R e s o l v e . i s A c c e s s i b l e (R e s o l v e . j a v a : 365) a t c o m . s u n . t o o l s . j a v a c . c o m p . R e s o l v e . s e l e c t B e s t (R e s o l v e . j a v a : 1463) a t c o m . s u n . t o o l s . j a v a c . c o m p . R e s o l v e . f i n d M e t h o d I n S c o p e (R e s o l v e . j a v a : 1633) a t c o m . s u n . t o o l s . j a v a c . c o m p . R e s o l v e . f i n d M e t h o d (R e s o l v e . j a v a : 1725) a t c o m . s u n . t o o l s . j a v a c . c o m p . R e s o l v e . f i n d M e t h o d (R e s o l v e . j a v a : 1677) a t c o m . s u n . t o o l s . j a v a c . c o m p . R e s o l v e$ MethodReferenceLookupHelper.lookup(Resolve.java:3192)
at com.sun.tools.javac.comp.Resolve.lookupMethod(Resolve.java:3348)
at com.sun.tools.javac.comp.Resolve.lookupMethod(Resolve.java:3333)
at com.sun.tools.javac.comp.Resolve.getMemberReference(Resolve.java:2741)
at com.sun.tools.javac.comp.DeferredAttr $D e f e r r e d C h e c k e r . v i s i t R e f e r e n c e (D e f e r r e d A t t r . j a v a : 1183) a t c o m . s u n . t o o l s . j a v a c . t r e e . J C T r e e$ JCMemberReference.accept(JCTree.java:1973)
at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
at com.sun.tools.javac.comp.DeferredAttr $F i l t e r S c a n n e r . s c a n (D e f e r r e d A t t r . j a v a : 913) a t c o m . s u n . t o o l s . j a v a c . c o m p . D e f e r r e d A t t r . i s D e f e r r e d (D e f e r r e d A t t r . j a v a : 1100) a t c o m . s u n . t o o l s . j a v a c . c o m p . A t t r . a t t r i b A r g s (A t t r . j a v a : 670) a t c o m . s u n . t o o l s . j a v a c . c o m p . A t t r . v i s i t A p p l y (A t t r . j a v a : 1816) a t c o m . s u n . t o o l s . j a v a c . t r e e . J C T r e e$ JCMethodInvocation.accept(JCTree.java:1465)
at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
at com.sun.tools.javac.comp.Attr.visitReturn(Attr.java:1686)
at com.sun.tools.javac.tree.JCTree $J C R e t u r n . a c c e p t (J C T r e e . j a v a : 1384) a t c o m . s u n . t o o l s . j a v a c . c o m p . A t t r . a t t r i b T r e e (A t t r . j a v a : 576) a t c o m . s u n . t o o l s . j a v a c . c o m p . A t t r . a t t r i b S t a t (A t t r . j a v a : 645) a t c o m . s u n . t o o l s . j a v a c . c o m p . A t t r . a t t r i b S t a t s (A t t r . j a v a : 661) a t c o m . s u n . t o o l s . j a v a c . c o m p . A t t r . v i s i t B l o c k (A t t r . j a v a : 1124) a t c o m . s u n . t o o l s . j a v a c . t r e e . J C T r e e$ JCBlock.accept(JCTree.java:909)
at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:645)
at com.sun.tools.javac.comp.Attr.visitMethodDef(Attr.java:1013)
at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:778)
at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:645)
at com.sun.tools.javac.comp.Attr.attribClassBody(Attr.java:4364)
at com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4272)
at com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4201)
at com.sun.tools.javac.comp.Attr.attrib(Attr.java:4176)
at com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:1248)
at com.sun.tools.javac.main.JavaCompiler.compile2(JavaCompiler.java:901)
at com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:860)
at com.sun.tools.javac.main.Main.compile(Main.java:523)
at com.sun.tools.javac.api.JavacTaskImpl.doCall(JavacTaskImpl.java:129)
at com.sun.tools.javac.api.JavacTaskImpl.call(JavacTaskImpl.java:138)
at org.codehaus.plexus.compiler.javac.JavaxToolsCompiler.compileInProcess(JavaxToolsCompiler.java:126)
at org.codehaus.plexus.compiler.javac.JavacCompiler.performCompile(JavacCompiler.java:169)
at org.apache.maven.plugin.compiler.AbstractCompilerMojo.execute(AbstractCompilerMojo.java:785)
at org.apache.maven.plugin.compiler.CompilerMojo.execute(CompilerMojo.java:129)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:137)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:210)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:156)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:148)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:117)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:81)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:56)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:305)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:192)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:105)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:957)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:289)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:193)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:282)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:225)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:406)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:347)

DEVICE_T是我的代码中一个泛型类的泛型参数，在代码中被广泛使用，代码有几千行，一时很难知道到底是哪一行代码出了问题。

同样的代码在Eclipse等IDE中编译可以通过，但是在命令行却不行(同样使用JDK8编译器),这一点我也很不解。

关于这个异常，网上是可以查到很多报告的，如：
https://github.com/oracle/graal/issues/4156
https://bugs.openjdk.org/browse/JDK-8273234
https://bugs.java.com/bugdatabase/view_bug.do?bug_id=8071783

按照《Exception java.lang.AssertionError: isSubClass when building Ghidra》的说明，这是个编译器的BUG,将在JDK 17解决。
我的项目是基于JDK8的，为了这个问题换编译器我可换不起。
只能用最笨的排除法，来尝试查找到底哪一部分的代码触发了这个BUG.
很幸运，最终找到了。
示例如下：

import com.google.common.base.Predicate;public abstract class DaoManagement<DEVICE_T extends DeviceBean>  extends BaseDao<DEVICE_T>{public abstract <B extends DEVICE_T> B copy(B bean, Predicate<Integer> fieldFilter,int... fieldList);public DEVICE_T copy(DEVICE_T deviceBean, DEVICE_T old){/** 在这种情况下，简化的lambda表达写法会引起编译错误 */ return copy(deviceBean, deviceBean::isModified,1,2,3);}
}
public interface BaseBean {public boolean isModified(int i);public boolean isModified(int... columnIDs);
}
public abstract class DeviceBean extends BaseRow{}
public abstract class BaseRow implements BaseBean{@Overridepublic boolean isModified(int i) {return false;}
}public abstract class BaseDao<DEVICE_T extends DeviceBean> {public DEVICE_T copy(DEVICE_T deviceBean, DEVICE_T old){return deviceBean;}
}

如上代码中使用了lambda表达式deviceBean::isModified，这这种写法在命令行编译时会抛出异常：java.lang.AssertionError: isSubClass DEVICE_T

改一下写法就行：v->deviceBean.isModified(v)，即：

public abstract class DaoManagement<DEVICE_T extends DeviceBean>  extends BaseDao<DEVICE_T>{public abstract <B extends DEVICE_T> B copy(B bean, Predicate<Integer> fieldFilter,int... fieldList);public DEVICE_T copy(DEVICE_T deviceBean, DEVICE_T old){return copy(deviceBean, v->deviceBean.isModified(v),1,2,3);}
}