https://www.graalvm.org/ 
public class com.oracle.truffle.api.dsl.test.GenericTypeCheckTest$MyTypeSytem
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: com.oracle.truffle.api.dsl.test.GenericTypeCheckTest$MyTypeSytem
  super_class: java.lang.Object
{
  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.api.dsl.test.GenericTypeCheckTest$MyTypeSytem this
         0: .line 86
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // com.oracle.truffle.api.dsl.test.GenericTypeCheckTest$MyTypeSytem this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/api/dsl/test/GenericTypeCheckTest$MyTypeSytem;
}
SourceFile: "GenericTypeCheckTest.java"
NestHost: com.oracle.truffle.api.dsl.test.GenericTypeCheckTest
InnerClasses:
  public MyTypeSytem = com.oracle.truffle.api.dsl.test.GenericTypeCheckTest$MyTypeSytem of com.oracle.truffle.api.dsl.test.GenericTypeCheckTest
    RuntimeInvisibleAnnotations: 
      com.oracle.truffle.api.dsl.TypeSystem(value = {Lcom/oracle/truffle/api/dsl/test/GenericTypeCheckTest$MyConcreteClass1;, Lcom/oracle/truffle/api/dsl/test/GenericTypeCheckTest$MyConcreteClass2;})