https://www.graalvm.org/ 
public interface com.oracle.truffle.api.TruffleLanguage$ContextThreadLocalFactory<C, T>
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: com.oracle.truffle.api.TruffleLanguage$ContextThreadLocalFactory
  super_class: java.lang.Object
{
  public abstract T create(C, java.lang.Thread);
    descriptor: (Ljava/lang/Object;Ljava/lang/Thread;)Ljava/lang/Object;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Signature: (TC;Ljava/lang/Thread;)TT;
    MethodParameters:
         Name  Flags
      context  
      thread   
}
Signature: <C:Ljava/lang/Object;T:Ljava/lang/Object;>Ljava/lang/Object;
SourceFile: "TruffleLanguage.java"
NestHost: com.oracle.truffle.api.TruffleLanguage
InnerClasses:
  protected abstract ContextThreadLocalFactory = com.oracle.truffle.api.TruffleLanguage$ContextThreadLocalFactory of com.oracle.truffle.api.TruffleLanguage
    RuntimeVisibleAnnotations: 
      java.lang.FunctionalInterface()