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Thread: how to check the value

  1. #1
    Junior Member
    Join Date
    Apr 2010
    Thanked 0 Times in 0 Posts

    Default how to check the value

    in my project...i had used jsp pages..if i enter value in jsp page..it should match with the parameter passed in servlet...and if it is checked it should do process...my project includes xml file..im not getting validated..can any one help me out..if that 'packName' is equal then only it should do deletion otherwise it should show me the message...here is my code


                            <td><font color="#800000">&nbsp;</font><font color="#800000"><b>Pack Name</b></font><font color="#800000" size="">&nbsp;</font></td>
                            <td><input name="packName" type="text" id="packName"> </td>


    package proj;
    import java.io.*;
    import java.io.IOException;
    import java.io.PrintWriter;
    import java.util.Properties;
    import javax.servlet.*;
    import javax.servlet.http.*;
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import org.w3c.dom.*;
    import javax.xml.parsers.*;
    import javax.xml.transform.*;
    import javax.xml.transform.dom.*;
    import javax.xml.transform.stream.*;
    public class delete extends HttpServlet {
        public void doPost(HttpServletRequest request, HttpServletResponse response)
                throws ServletException, IOException {
            PrintWriter pw = response.getWriter();
            String s = null;
            String packName = request.getParameter("packName");
            try {
                DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();
                DocumentBuilder docBuilder = builderFactory.newDocumentBuilder();
                // Creating the path for XML File using Properties
                ServletContext servletContextObj = request.getSession().getServletContext();
                String excelTemplatesPath = servletContextObj.getRealPath("/");
                String filePaths = excelTemplatesPath + File.separator
                        + "config.properties";
                Properties propObj = new Properties();
                propObj.load(new FileInputStream(filePaths));
                String gprsLoginPath = null;
                gprsLoginPath = propObj.getProperty("GPRS_LOGIN_PATH");
                if (gprsLoginPath == null || gprsLoginPath.trim().equals("")) {
                    gprsLoginPath = excelTemplatesPath;
                gprsLoginPath += File.separator + "login.xml";
                java.io.File file = new java.io.File(gprsLoginPath);
                Document doc = null;
                if (file.exists()) {
                    try {
                        doc = docBuilder.parse(file);
                    } catch (Exception ex) {
                        doc = docBuilder.newDocument();
                        Element root = doc.createElement("PACKS");
                } else {
                    doc = docBuilder.newDocument();
                    // Creating Root Tag
                    Element root = doc.createElement("PACKS");
                // creating a new instance of a DOM to build a DOM tree.
                // Document doc = docBuilder.newDocument();
                delNode(file, doc, "PACK_NAME");
                pw.println("<b>Xml File Deleted Successfully</b>");
            } catch (Exception e) {
        public static void delNode(java.io.File file, Node parent, String filter)
                throws Exception {
            NodeList children = parent.getChildNodes();
            for (int i = 0; i < children.getLength(); i++) {
                Node child = children.item(i);
                if (child.getNodeType() == Node.ELEMENT_NODE) {
                    if (child.getNodeName().equals(filter)) {
                    } else {
                        delNode(file, child, filter);
            // TransformerFactory instance is used to create Transformer objects.
            TransformerFactory factory = TransformerFactory.newInstance();
            Transformer transformer = factory.newTransformer();
            transformer.setOutputProperty(OutputKeys.INDENT, "yes");
            // create string from xml tree
            StringWriter sw = new StringWriter();
            StreamResult result = new StreamResult(sw);
            //Document doc = null;
            DOMSource source = new DOMSource(parent);
            transformer.transform(source, result);
            String xmlString = sw.toString();
            //File file = new File("E:/xgprs/xmlgprs/login.xml");
            BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(
                    new FileOutputStream(file)));

    thanks in advance..waiting for the reply..

  2. #2
    Forum VIP
    Join Date
    Jul 2010
    Thanked 329 Times in 305 Posts

    Default Re: how to check the value

    Ok, well I dont know anything about this jsp stuff, but I can help you figure out what it is currently doing.

    Basic Run-Time Debugging includes placing appropriate System.out.println statements to discover exactly what it is doing. So, the first thing you want to do is figure out what the two values you are comparing are equal to when you compare them. So, right before you do the comparing, but the statements:
    System.out.println("PackName = "+packName);
    System.out.println("Other Variable = "+otherVariable);
    Change Other Variable to the variable you are comparing to PackName. From there, we can discover what exactly is happening and work from there.
    Last edited by aussiemcgr; July 21st, 2010 at 11:50 AM.

  3. #3
    Junior Member
    Join Date
    Apr 2010
    Thanked 0 Times in 0 Posts

    Default Re: how to check the value

    thanks for you reply...i got it.. i need another help..my doubt is if im going to delete data in xml file...im getting white spaces..but i dont need whitespaces...can you help me how to remove the white spaces...here is my code...

    private void delNode(java.io.File file, Document parent, String filtervalue)
                  throws Exception
            NodeList nodeList = parent.getElementsByTagName("PACK_NAME");
            for (int i = 0; i < nodeList.getLength(); i++) {
                Node child = nodeList.item(i);
                System.out.println("child " + child.getTextContent());
                if (child.getTextContent() != null && child.getTextContent().trim().equalsIgnoreCase(filtervalue.trim())) {
                    Node packNode = child.getParentNode().getParentNode();
                    Node packsNode = parent.getFirstChild();

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