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) 
final class org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator extends org.apache.fop.pdf.FileIDGenerator
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator
  super_class: org.apache.fop.pdf.FileIDGenerator
{
  private byte[] fileID;
    descriptor: [B
    flags: (0x0002) ACC_PRIVATE

  private void <init>();
    descriptor: ()V
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=2, locals=2, args_size=1
        start local 0 // org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator this
         0: .line 43
            aload 0 /* this */
            invokespecial org.apache.fop.pdf.FileIDGenerator.<init>:()V
         1: .line 44
            new java.util.Random
            dup
            invokespecial java.util.Random.<init>:()V
            astore 1 /* random */
        start local 1 // java.util.Random random
         2: .line 45
            aload 0 /* this */
            bipush 16
            newarray 8
            putfield org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator.fileID:[B
         3: .line 46
            aload 1 /* random */
            aload 0 /* this */
            getfield org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator.fileID:[B
            invokevirtual java.util.Random.nextBytes:([B)V
         4: .line 47
            return
        end local 1 // java.util.Random random
        end local 0 // org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator this
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    5     0    this  Lorg/apache/fop/pdf/FileIDGenerator$RandomFileIDGenerator;
            2    5     1  random  Ljava/util/Random;

  byte[] getOriginalFileID();
    descriptor: ()[B
    flags: (0x0000) 
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator this
         0: .line 51
            aload 0 /* this */
            getfield org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator.fileID:[B
            areturn
        end local 0 // org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/apache/fop/pdf/FileIDGenerator$RandomFileIDGenerator;

  byte[] getUpdatedFileID();
    descriptor: ()[B
    flags: (0x0000) 
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator this
         0: .line 56
            aload 0 /* this */
            getfield org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator.fileID:[B
            areturn
        end local 0 // org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/apache/fop/pdf/FileIDGenerator$RandomFileIDGenerator;
}
SourceFile: "FileIDGenerator.java"
NestHost: org.apache.fop.pdf.FileIDGenerator
InnerClasses:
  private final RandomFileIDGenerator = org.apache.fop.pdf.FileIDGenerator$RandomFileIDGenerator of org.apache.fop.pdf.FileIDGenerator