https://www.graalvm.org/ 
public class com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal extends com.oracle.truffle.api.TruffleLanguage<com.oracle.truffle.api.TruffleLanguage$Env>
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal
  super_class: com.oracle.truffle.api.TruffleLanguage
{
  static int effect;
    descriptor: I
    flags: (0x0008) ACC_STATIC

  final com.oracle.truffle.api.ContextThreadLocal<com.oracle.truffle.api.TruffleLanguage$Env> local0;
    descriptor: Lcom/oracle/truffle/api/ContextThreadLocal;
    flags: (0x0010) ACC_FINAL
    Signature: Lcom/oracle/truffle/api/ContextThreadLocal<Lcom/oracle/truffle/api/TruffleLanguage$Env;>;

  final com.oracle.truffle.api.ContextThreadLocal<com.oracle.truffle.api.TruffleLanguage$Env> local1;
    descriptor: Lcom/oracle/truffle/api/ContextThreadLocal;
    flags: (0x0010) ACC_FINAL
    Signature: Lcom/oracle/truffle/api/ContextThreadLocal<Lcom/oracle/truffle/api/TruffleLanguage$Env;>;

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: .line 870
            iconst_0
            putstatic com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal.effect:I
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=4, locals=1, args_size=1
        start local 0 // com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal this
         0: .line 868
            aload 0 /* this */
            invokespecial com.oracle.truffle.api.TruffleLanguage.<init>:()V
         1: .line 872
            aload 0 /* this */
            aload 0 /* this */
            invokedynamic create()Lcom/oracle/truffle/api/TruffleLanguage$ContextThreadLocalFactory;
              Bootstrap: invokestatic java.lang.invoke.LambdaMetafactory.metafactory:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite;
                Method arguments:
                  (Ljava/lang/Object;Ljava/lang/Thread;)Ljava/lang/Object;
                  com/oracle/truffle/api/test/polyglot/ContextLocalTest$InvalidLanguageContextThreadLocal.lambda$0(Lcom/oracle/truffle/api/TruffleLanguage$Env;Ljava/lang/Thread;)Lcom/oracle/truffle/api/TruffleLanguage$Env; (6)
                  (Lcom/oracle/truffle/api/TruffleLanguage$Env;Ljava/lang/Thread;)Lcom/oracle/truffle/api/TruffleLanguage$Env;
            invokevirtual com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal.createContextThreadLocal:(Lcom/oracle/truffle/api/TruffleLanguage$ContextThreadLocalFactory;)Lcom/oracle/truffle/api/ContextThreadLocal;
            putfield com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal.local0:Lcom/oracle/truffle/api/ContextThreadLocal;
         2: .line 873
            aload 0 /* this */
            getstatic com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal.effect:I
            dup
            iconst_1
            iadd
            putstatic com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal.effect:I
            iconst_2
            irem
            ifne 3
            aload 0 /* this */
            invokedynamic create()Lcom/oracle/truffle/api/TruffleLanguage$ContextThreadLocalFactory;
              Bootstrap: invokestatic java.lang.invoke.LambdaMetafactory.metafactory:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite;
                Method arguments:
                  (Ljava/lang/Object;Ljava/lang/Thread;)Ljava/lang/Object;
                  com/oracle/truffle/api/test/polyglot/ContextLocalTest$InvalidLanguageContextThreadLocal.lambda$1(Lcom/oracle/truffle/api/TruffleLanguage$Env;Ljava/lang/Thread;)Lcom/oracle/truffle/api/TruffleLanguage$Env; (6)
                  (Lcom/oracle/truffle/api/TruffleLanguage$Env;Ljava/lang/Thread;)Lcom/oracle/truffle/api/TruffleLanguage$Env;
            invokevirtual com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal.createContextThreadLocal:(Lcom/oracle/truffle/api/TruffleLanguage$ContextThreadLocalFactory;)Lcom/oracle/truffle/api/ContextThreadLocal;
            goto 4
      StackMap locals: com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal
      StackMap stack: com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal
         3: aconst_null
      StackMap locals: com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal
      StackMap stack: com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal com.oracle.truffle.api.ContextThreadLocal
         4: putfield com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal.local1:Lcom/oracle/truffle/api/ContextThreadLocal;
         5: .line 868
            return
        end local 0 // com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    6     0  this  Lcom/oracle/truffle/api/test/polyglot/ContextLocalTest$InvalidLanguageContextThreadLocal;

  protected com.oracle.truffle.api.TruffleLanguage$Env createContext(com.oracle.truffle.api.TruffleLanguage$Env);
    descriptor: (Lcom/oracle/truffle/api/TruffleLanguage$Env;)Lcom/oracle/truffle/api/TruffleLanguage$Env;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=1, locals=2, args_size=2
        start local 0 // com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal this
        start local 1 // com.oracle.truffle.api.TruffleLanguage$Env env
         0: .line 877
            aload 1 /* env */
            areturn
        end local 1 // com.oracle.truffle.api.TruffleLanguage$Env env
        end local 0 // com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/api/test/polyglot/ContextLocalTest$InvalidLanguageContextThreadLocal;
            0    1     1   env  Lcom/oracle/truffle/api/TruffleLanguage$Env;
    MethodParameters:
      Name  Flags
      env   

  protected java.lang.Object createContext(com.oracle.truffle.api.TruffleLanguage$Env);
    descriptor: (Lcom/oracle/truffle/api/TruffleLanguage$Env;)Ljava/lang/Object;
    flags: (0x1044) ACC_PROTECTED, ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=2, locals=2, args_size=2
         0: .line 1
            aload 0
            aload 1
            invokevirtual com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal.createContext:(Lcom/oracle/truffle/api/TruffleLanguage$Env;)Lcom/oracle/truffle/api/TruffleLanguage$Env;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  private static com.oracle.truffle.api.TruffleLanguage$Env lambda$0(com.oracle.truffle.api.TruffleLanguage$Env, java.lang.Thread);
    descriptor: (Lcom/oracle/truffle/api/TruffleLanguage$Env;Ljava/lang/Thread;)Lcom/oracle/truffle/api/TruffleLanguage$Env;
    flags: (0x100a) ACC_PRIVATE, ACC_STATIC, ACC_SYNTHETIC
    Code:
      stack=1, locals=2, args_size=2
        start local 0 // com.oracle.truffle.api.TruffleLanguage$Env e
        start local 1 // java.lang.Thread t
         0: .line 872
            aload 0 /* e */
            areturn
        end local 1 // java.lang.Thread t
        end local 0 // com.oracle.truffle.api.TruffleLanguage$Env e
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0     e  Lcom/oracle/truffle/api/TruffleLanguage$Env;
            0    1     1     t  Ljava/lang/Thread;

  private static com.oracle.truffle.api.TruffleLanguage$Env lambda$1(com.oracle.truffle.api.TruffleLanguage$Env, java.lang.Thread);
    descriptor: (Lcom/oracle/truffle/api/TruffleLanguage$Env;Ljava/lang/Thread;)Lcom/oracle/truffle/api/TruffleLanguage$Env;
    flags: (0x100a) ACC_PRIVATE, ACC_STATIC, ACC_SYNTHETIC
    Code:
      stack=1, locals=2, args_size=2
        start local 0 // com.oracle.truffle.api.TruffleLanguage$Env e
        start local 1 // java.lang.Thread t
         0: .line 873
            aload 0 /* e */
            areturn
        end local 1 // java.lang.Thread t
        end local 0 // com.oracle.truffle.api.TruffleLanguage$Env e
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0     e  Lcom/oracle/truffle/api/TruffleLanguage$Env;
            0    1     1     t  Ljava/lang/Thread;
}
Signature: Lcom/oracle/truffle/api/TruffleLanguage<Lcom/oracle/truffle/api/TruffleLanguage$Env;>;
SourceFile: "ContextLocalTest.java"
NestHost: com.oracle.truffle.api.test.polyglot.ContextLocalTest
InnerClasses:
  protected abstract ContextThreadLocalFactory = com.oracle.truffle.api.TruffleLanguage$ContextThreadLocalFactory of com.oracle.truffle.api.TruffleLanguage
  public final Env = com.oracle.truffle.api.TruffleLanguage$Env of com.oracle.truffle.api.TruffleLanguage
  public abstract Registration = com.oracle.truffle.api.TruffleLanguage$Registration of com.oracle.truffle.api.TruffleLanguage
  public InvalidLanguageContextThreadLocal = com.oracle.truffle.api.test.polyglot.ContextLocalTest$InvalidLanguageContextThreadLocal of com.oracle.truffle.api.test.polyglot.ContextLocalTest
  public final Lookup = java.lang.invoke.MethodHandles$Lookup of java.lang.invoke.MethodHandles
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.TruffleLanguage$Registration(id = "ContextLocalTest_InvalidLanguageContextThreadLocal", name = "ContextLocalTest_InvalidLanguageContextThreadLocal")