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) 
public class org.apache.fop.pdf.PDFStructTreeRoot extends org.apache.fop.pdf.StructureHierarchyMember
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: org.apache.fop.pdf.PDFStructTreeRoot
  super_class: org.apache.fop.pdf.StructureHierarchyMember
{
  void <init>(org.apache.fop.pdf.PDFParentTree);
    descriptor: (Lorg/apache/fop/pdf/PDFParentTree;)V
    flags: (0x0000) 
    Code:
      stack=5, locals=2, args_size=2
        start local 0 // org.apache.fop.pdf.PDFStructTreeRoot this
        start local 1 // org.apache.fop.pdf.PDFParentTree parentTree
         0: .line 32
            aload 0 /* this */
            invokespecial org.apache.fop.pdf.StructureHierarchyMember.<init>:()V
         1: .line 33
            aload 0 /* this */
            ldc "Type"
            new org.apache.fop.pdf.PDFName
            dup
            ldc "StructTreeRoot"
            invokespecial org.apache.fop.pdf.PDFName.<init>:(Ljava/lang/String;)V
            invokevirtual org.apache.fop.pdf.PDFStructTreeRoot.put:(Ljava/lang/String;Ljava/lang/Object;)V
         2: .line 34
            aload 0 /* this */
            ldc "K"
            new org.apache.fop.pdf.PDFArray
            dup
            invokespecial org.apache.fop.pdf.PDFArray.<init>:()V
            invokevirtual org.apache.fop.pdf.PDFStructTreeRoot.put:(Ljava/lang/String;Ljava/lang/Object;)V
         3: .line 35
            aload 0 /* this */
            ldc "ParentTree"
            aload 1 /* parentTree */
            invokevirtual org.apache.fop.pdf.PDFStructTreeRoot.put:(Ljava/lang/String;Ljava/lang/Object;)V
         4: .line 36
            return
        end local 1 // org.apache.fop.pdf.PDFParentTree parentTree
        end local 0 // org.apache.fop.pdf.PDFStructTreeRoot this
      LocalVariableTable:
        Start  End  Slot        Name  Signature
            0    5     0        this  Lorg/apache/fop/pdf/PDFStructTreeRoot;
            0    5     1  parentTree  Lorg/apache/fop/pdf/PDFParentTree;
    MethodParameters:
            Name  Flags
      parentTree  

  public org.apache.fop.pdf.PDFArray getKids();
    descriptor: ()Lorg/apache/fop/pdf/PDFArray;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // org.apache.fop.pdf.PDFStructTreeRoot this
         0: .line 44
            aload 0 /* this */
            ldc "K"
            invokevirtual org.apache.fop.pdf.PDFStructTreeRoot.get:(Ljava/lang/String;)Ljava/lang/Object;
            checkcast org.apache.fop.pdf.PDFArray
            areturn
        end local 0 // org.apache.fop.pdf.PDFStructTreeRoot this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/apache/fop/pdf/PDFStructTreeRoot;

  public void addKid(org.apache.fop.pdf.PDFObject);
    descriptor: (Lorg/apache/fop/pdf/PDFObject;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // org.apache.fop.pdf.PDFStructTreeRoot this
        start local 1 // org.apache.fop.pdf.PDFObject kid
         0: .line 54
            aload 0 /* this */
            invokevirtual org.apache.fop.pdf.PDFStructTreeRoot.getKids:()Lorg/apache/fop/pdf/PDFArray;
            aload 1 /* kid */
            invokevirtual org.apache.fop.pdf.PDFArray.add:(Ljava/lang/Object;)V
         1: .line 55
            return
        end local 1 // org.apache.fop.pdf.PDFObject kid
        end local 0 // org.apache.fop.pdf.PDFStructTreeRoot this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lorg/apache/fop/pdf/PDFStructTreeRoot;
            0    2     1   kid  Lorg/apache/fop/pdf/PDFObject;
    MethodParameters:
      Name  Flags
      kid   
}
SourceFile: "PDFStructTreeRoot.java"