Java Utililty Methods XML Parse InputSource

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setAttribute("http://java.sun.com/xml/jaxp/properties/schemaLanguage",
        "http://www.w3.org/2001/XMLSchema");
factory.setNamespaceAware(true);
factory.setValidating(true);
DocumentBuilder parser = factory.newDocumentBuilder();
final Map<String, String> system = new HashMap<String, String>();
system.put("http://www.jboss.org/j2ee/schema/jboss-ejb3-2_0.xsd", "/schema/jboss-ejb3-2_0.xsd");
...

try {
    DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
    DocumentBuilder db = dbf.newDocumentBuilder();
    return db.parse(in);
} catch (Exception e) {
    e.printStackTrace();
    return null;

DocumentBuilder builder = null;
DocumentBuilderFactory factory = getFactory(validate, namespaceAware);
try {
    builder = factory.newDocumentBuilder();
} catch (ParserConfigurationException ex) {
    throw new SAXException("Cannot create parser satisfying configuration parameters", ex); 
if (errorHandler != null) {
...

try {
    return getDocumentBuilder().parse(source).getDocumentElement();
} catch (SAXException se) {
    throw new IOException(se.toString());
} finally {
    InputStream is = source.getByteStream();
    if (is != null) {
        is.close();
...

try {
    Document doc = null;
    DocumentBuilder documentBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
    doc = documentBuilder.parse(is);
    return doc;
} catch (Exception e) {
    throw new RuntimeException("Failed to parse XML source", e);