is = new ByteArrayInputStream(s.getBytes());
Document doc = builder.parse(is);
NodeList nl = doc.getElementsByTagName("img");
for (int i = 0; i < nl.getLength(); i++) {
Node n = nl.item(i);
Node srcNode = n.getAttributes().getNamedItem("src");
String srcText = srcNode.getNodeValue();
String newText = getRealPath(srcText, host, url);
String cleanText = cleanPath(newText);
srcNode.setNodeValue(cleanText);
}
renderer.setDocument(doc, null);
// renderer.setDocument("http://www.w3.org/");
renderer.layout();