https://openjdk.java.net/ 
public interface java.lang.reflect.WildcardType extends java.lang.reflect.Type
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: java.lang.reflect.WildcardType
  super_class: java.lang.Object
{
  public abstract java.lang.reflect.Type[] getUpperBounds();
    descriptor: ()[Ljava/lang/reflect/Type;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract java.lang.reflect.Type[] getLowerBounds();
    descriptor: ()[Ljava/lang/reflect/Type;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
}
SourceFile: "WildcardType.java"