https://openjdk.java.net/ 
public interface java.security.cert.Extension
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: java.security.cert.Extension
  super_class: java.lang.Object
{
  public abstract java.lang.String getId();
    descriptor: ()Ljava/lang/String;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract boolean isCritical();
    descriptor: ()Z
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract byte[] getValue();
    descriptor: ()[B
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract void encode(java.io.OutputStream);
    descriptor: (Ljava/io/OutputStream;)V
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Exceptions:
      throws java.io.IOException
    MethodParameters:
      Name  Flags
      out   
}
SourceFile: "Extension.java"