Unable to create child elements.... XMl Parsing...

[Jigar Naik]

hi folloing is the structure of my XML file

XML file : bofore adding child node to root node.

<?xml version="1.0" encoding="UTF-8"?><blog create-date="2007-03-14 17:52:57" created-by="Amish Desai" title="unble to parse xml">
</blog>

Method to add child node to a parent node

 
public void create_xml(){
try{
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = new Date();
        String c_date = dateFormat.format(date).toString();
parse_conn_xml();
String filename1="";
prop.load(connProp);
Class.forName(connectionClass);
Connection conn = DriverManager.getConnection(connectionName);
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("Select max(id) from blog");
rs.next();
filename1 = rs.getString(1);
String filename = "D:/usr/jboss/server/default/deploy/blog/" + filename1 + ".xml";

File file = new File(filename);
file.createNewFile();
BufferedWriter out = new BufferedWriter(new FileWriter(filename));

out.write("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
out.write("\r\n");
        out.write("<blog>");
        out.write("\r\n");
        out.write("</blog>");
        out.write("\r\n");
        out.close();

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new InputSource(filename));
doc.getDocumentElement().setAttribute("created-by",BlogBean.getCreated_by());
doc.getDocumentElement().setAttribute("title",BlogBean.getTitle());
doc.getDocumentElement().setAttribute("create-date",c_date);

Node post = doc.createElement("post");
post.setTextContent(BlogBean.getPost());

[I]Element element = (Element)doc.getElementsByTagName("blog");[/I]    [I][B]line no : 130[/B][/I]
//Element element = (Element)doc.getElementsByTagName("blog");
//System.out.println("Node Name : " + element.getNodeName());
//element.appendChild(post);
//doc.getParentNode().appendChild(post));

//Transftering s
DOMSource ds = new DOMSource(doc);
StreamResult sr = new StreamResult(new File(filename));
TransformerFactory tf = TransformerFactory.newInstance();
Transformer trans = tf.newTransformer();
trans.transform(ds,sr);
}catch(Exception e){
System.out.println("*** EXCEPTION IN CREATE_XML METHOD ***");
e.printStackTrace();
}
}

ERROR I'm getting :

   
10:56:53,375 INFO  [STDOUT] *** EXCEPTION IN CREATE_XML METHOD ***
10:56:53,375 ERROR [STDERR] java.lang.ClassCastException: org.apache.xerces.dom.DeepNodeListImpl
10:56:53,375 ERROR [STDERR] at com.tg.utils.Blog.create_xml(Blog.java:130)
10:56:53,375 ERROR [STDERR] at com.tg.servlets.Controller.doPost(Controller.java:39)
10:56:53,375 ERROR [STDERR] at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
10:56:53,375 ERROR [STDERR] at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
10:56:53,375 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
10:56:53,375 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
10:56:53,375 ERROR [STDERR] at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
10:56:53,375 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
10:56:53,375 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
10:56:53,375 ERROR [STDERR] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
10:56:53,375 ERROR [STDERR] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
10:56:53,375 ERROR [STDERR] at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:175)
10:56:53,375 ERROR [STDERR] at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:74)
10:56:53,375 ERROR [STDERR] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
10:56:53,375 ERROR [STDERR] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
10:56:53,375 ERROR [STDERR] at org.jboss.web.tomcat.tc5.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:156)
10:56:53,375 ERROR [STDERR] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
10:56:53,375 ERROR [STDERR] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
10:56:53,375 ERROR [STDERR] at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
10:56:53,375 ERROR [STDERR] at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
10:56:53,375 ERROR [STDERR] at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
10:56:53,375 ERROR [STDERR] at org.apache.tomcat.util.net.MasterSlaveWorkerThread.run(MasterSlaveWorkerThread.java:112)
10:56:53,375 ERROR [STDERR] at java.lang.Thread.run(Thread.java:595)

[Ulf Dittmer]

getElementsByTagName returns a NodeList, not an Element. I'm curious how that code can even compile.

If you're certain that the list only contains a single element, then something like

Element element = (Element) doc.getElementsByTagName("blog").item(0);

[Jigar Naik]

ya i did that and its working fine...

 
//Creating a DOM
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new InputSource(filename));

doc.getDocumentElement().setAttribute("created-by",BlogBean.getCreated_by());//Setting attribute to root node Blog
doc.getDocumentElement().setAttribute("title",BlogBean.getTitle());//Setting attribute to root node Blog
doc.getDocumentElement().setAttribute("create-date",c_date);//Setting attribute to root node Blog

Element post = doc.createElement("post");//Created a new independent Node/Element
post.setTextContent(BlogBean.getPost());//Adding a value to independent Node/Element
post.setAttribute("posted-by",BlogBean.getCreated_by());//Adding attribute to independent element
post.setAttribute("posted_on",c_date);//Adding attribues to independent element

Element element = (Element)doc.getElementsByTagName("blog").item(0);//Getting to root node/element
element.appendChild(post);//Adding the independent element/node to root node/element
 
//Transformation
DOMSource ds = new DOMSource(doc);
StreamResult sr = new StreamResult(new File(filename));
TransformerFactory tf = TransformerFactory.newInstance();
Transformer trans = tf.newTransformer();
trans.transform(ds,sr);

Thanks....