https://openjdk.java.net/ 
public interface com.sun.security.auth.PrincipalComparator
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: com.sun.security.auth.PrincipalComparator
  super_class: java.lang.Object
{
  public abstract boolean implies(javax.security.auth.Subject);
    descriptor: (Ljavax/security/auth/Subject;)Z
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    MethodParameters:
         Name  Flags
      subject  
}
SourceFile: "PrincipalComparator.java"