http://xmlgraphics.apache.org/fop/: Apache FOP (Formatting Objects Processor) is the world's first print formatter driven by XSL formatting objects (XSL-FO) and the world's first output independent formatter. It is a Java application that reads a formatting object (FO) tree and renders the resulting pages to a specified output. Output formats currently supported include PDF, PCL, PS, AFP, TIFF, PNG, SVG, XML (area tree representation), Print, AWT and TXT. The primary output target is PDF. (Apache Software Foundation) 
abstract class org.apache.fop.pdf.FileIDGenerator
  minor version: 0
  major version: 59
  flags: flags: (0x0420) ACC_SUPER, ACC_ABSTRACT
  this_class: org.apache.fop.pdf.FileIDGenerator
  super_class: java.lang.Object
{
  void <init>();
    descriptor: ()V
    flags: (0x0000) 
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // org.apache.fop.pdf.FileIDGenerator this
         0: .line 33
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // org.apache.fop.pdf.FileIDGenerator this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/apache/fop/pdf/FileIDGenerator;

  abstract byte[] getOriginalFileID();
    descriptor: ()[B
    flags: (0x0400) ACC_ABSTRACT

  abstract byte[] getUpdatedFileID();
    descriptor: ()[B
    flags: (0x0400) ACC_ABSTRACT

  static org.apache.fop.pdf.FileIDGenerator getRandomFileIDGenerator();
    descriptor: ()Lorg/apache/fop/pdf/FileIDGenerator;
    flags: (0x0008) ACC_STATIC
    Code:
      stack=2, locals=0, args_size=0
         0: .line 108
            new org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator
            dup
            invokespecial org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator.<init>:()V
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  static org.apache.fop.pdf.FileIDGenerator getDigestFileIDGenerator(org.apache.fop.pdf.PDFDocument);
    descriptor: (Lorg/apache/fop/pdf/PDFDocument;)Lorg/apache/fop/pdf/FileIDGenerator;
    flags: (0x0008) ACC_STATIC
    Code:
      stack=3, locals=1, args_size=1
        start local 0 // org.apache.fop.pdf.PDFDocument document
         0: .line 122
            new org.apache.fop.pdf.FileIDGenerator$DigestFileIDGenerator
            dup
            aload 0 /* document */
            invokespecial org.apache.fop.pdf.FileIDGenerator$DigestFileIDGenerator.<init>:(Lorg/apache/fop/pdf/PDFDocument;)V
            areturn
        end local 0 // org.apache.fop.pdf.PDFDocument document
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0    1     0  document  Lorg/apache/fop/pdf/PDFDocument;
    Exceptions:
      throws java.security.NoSuchAlgorithmException
    MethodParameters:
          Name  Flags
      document  
}
SourceFile: "FileIDGenerator.java"
NestMembers:
  org.apache.fop.pdf.FileIDGenerator$DigestFileIDGenerator  org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator
InnerClasses:
  private final DigestFileIDGenerator = org.apache.fop.pdf.FileIDGenerator$DigestFileIDGenerator of org.apache.fop.pdf.FileIDGenerator
  private final RandomFileIDGenerator = org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator of org.apache.fop.pdf.FileIDGenerator