VTD-XML: The Future of XML Processing

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Edit XML content

(For more code samples, visit Official VTD-XML Blog)

(Separate code-only VTD-XML tutorials are available in C, C++, Java and C#)

This application shows you how to "fill in" text content of template XML documents (one with white spaces text content intended to be overwritten). In this case, an XML document becomes an empty form and your application just fills in the value. The white spaces have to be wider than the new content, otherwise the operation will not work. The implication is that now you can generate those XML document templates and use VTD-XML as a form "filler" to dramatically speed up the serialization performance.

The files for this example are listed below:




The input and output of the application looks like this:

Input Output
     <a> some content </a>
     <b>                      </b>
     <c>                      </c>
     <a> 123            </a>
     <b> 234            </b>
     <c>new content </c>


The application logic goes into the following code block.

import com.ximpleware.*;
import java.io.*;

public class overWrite {
       public static void main(String[] args) throws Exception {

              // logic goes here



The application logic basically visits individual element a, b and c, then calls "overWrite(...)" to fill in new content. The function "overWrite(...)" returns true if successful. Otherwise, it returns false, indicating the length of the token (to be overwritten) is not wide enough to hold the new content. The other thing worth noting: if "overWrite" is successful, it will completely replace the byte content of the token with new content and white spaces.

VTDGen vg = new VTDGen();
if (vg.parseFile("old.xml",false)){
            VTDNav vn = vg.getNav();
            if (vn.toElement(VTDNav.FIRST_CHILD)){
                     // cursor at <a>
                     int i = vn.getText();
                     if (vn.overWrite(i," 123".getBytes())==false){
                           System.out.println("overWrite at "+i+" failed");
                     // cursor at <b>
                     i = vn.getText();
                     if (vn.overWrite(i," 234".getBytes())==false){
                           System.out.println("overWrite at "+i+" failed");
                     // cursor at <c>
                     i = vn.getText();
                     if (vn.overWrite(i,"new content".getBytes())==false){
                          System.out.println("overWrite at "+i+" failed");
                     // get the byte array of overwritten XML
                     byte[] ba = vn.getXML().getBytes();
                     FileOutputStream fos = new FileOutputStream("new.xml");

VTD in 30 seconds

VTD+XML Format

User's Guide

Developer's Guide

VTD: A Technical Perspective

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