Java Utililty Methods XML Document to Writer

if (doc == null || writer == null) {
    return;
try {
    Transformer tran = tf.newTransformer();
    tran.setOutputProperty(OutputKeys.INDENT, "yes");
    Source src = new DOMSource(doc);
    Result res = new StreamResult(writer);
...

try {
    Source source = new DOMSource(doc);
    Result result = new StreamResult(w);
    Transformer xformer = s_xformer_factory.newTransformer();
    xformer.transform(source, result);
} catch (TransformerConfigurationException e) {
    throw new RuntimeException("Configuration Exception writing XML: " + e);
} catch (TransformerException e) {
...

try {
    new DefaultEditorKit().write(out, doc, 0, doc.getLength());
} catch (BadLocationException e) {
    throw new IOException(e.getMessage());

DOMImplementationLS impl = (DOMImplementationLS) doc.getImplementation();
LSSerializer writer = impl.createLSSerializer();
DOMConfiguration config = writer.getDomConfig();
if (config.canSetParameter("format-pretty-print", Boolean.TRUE)) {
    config.setParameter("format-pretty-print", Boolean.TRUE);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
LSOutput output = impl.createLSOutput();
...

for (Node n = doc.getFirstChild(); n != null; n = n.getNextSibling()) {
    writeNode(n, w);

TransformerFactory tf = TransformerFactory.newInstance();
try {
    Transformer trans = tf.newTransformer();
    if (indent != null) {
        trans.setOutputProperty(OutputKeys.INDENT, "yes");
        trans.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", String.valueOf(indent));
    trans.transform(new DOMSource(document), new StreamResult(writer));
...

w.println("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
Node c = d.getFirstChild();
while (c != null) {
    writeNode(w, c, 0);
    c = c.getNextSibling();

DOMSource docSource = new DOMSource(doc);
Transformer transformer = getXmlTransformer();
transformer.transform(docSource, new StreamResult(w));

Result result = new StreamResult(writer);
DOMSource domSource = new DOMSource(doc);
Transformer transformer = TransformerFactory.newInstance().newTransformer();
transformer.setOutputProperty("omit-xml-declaration", "yes");
transformer.transform(domSource, result);

writeXML(doc, writer, null);