using java dom to update file

I've the following code and this html file. I'm trying to locate the <head> tag and add text in between it, however it isn't working. Could someone please take a look at my code and tell me what is missing? Thanks.

<xml version="1.0" encoding="UTF-8"?/>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html"/>
<meta http-equiv="Content-Style-Type" content="text/css"/>
<title>a title</title>
</head>
<body>
<p>some text</p>
</body>
</html>

Code:

ocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); try { DocumentBuilder db = dbf.newDocumentBuilder(); Document doc = db.parse(new File("test.html")); String newinfo = "text to be added"; Element root = doc.getDocumentElement(); NodeList rootlist = root.getChildNodes(); for(int i=0; i<rootlist.getLength(); i++) { Element head = (Element)rootlist.item(i); NodeList namelist = head.getChildNodes(); Text headtext = (Text)namelist.item(0); String oldname = headtext.getData(); if(oldname.equals(newinfo)) { Element head2 = (Element)namelist.item(1); NodeList namelist2 = head.getChildNodes(); Text headtext2 = (Text)namelist.item(0); headtext.setData(newinfo); } } } catch (Exception e) { e.printStackTrace(); }

If you'll post code that compiles and executes, it'd be easier to test.

Also show the type of data you want to add. Is it HTML with special chars or just text?

It is just text that should be added between the <head> tags. i'll keep trying to work on the code to make it compile but in the meanwhile any ideas why it isn't would be greatly appreciated.

updated code

This is what I have so far, it compiles but does not accomplish what I need it to:

Code:

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); try { DocumentBuilder db = dbf.newDocumentBuilder(); Document doc = db.parse(new File("testing.html")); String newinfo = "text to be added"; Element root = doc.getDocumentElement(); NodeList rootlist = root.getChildNodes(); Node current = null; int count = rootlist.getLength(); for (int i = 0; i < count; i++) { current = rootlist.item(i); if(current.getNodeType() == Node.ELEMENT_NODE) { Element element = (Element)current; NodeList children = element.getChildNodes(); if(element.getTagName().equalsIgnoreCase("head")) { Text headtext = (Text)children.item(0); headtext.setData(newinfo); } } System.out.println(doc.getDocumentElement()); } } catch (Exception e) { e.printStackTrace(); }

Quote:

If you'll post code that compiles and executes, it'd be easier to test.

That would include everything from import to ending }

Quote:

it compiles

You have a better compiler than mine then.

complete code

Code:

import java.io.File; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.NodeList; import com.sun.org.apache.xml.internal.serialize.XMLSerializer; // using DOM public class testingWriteToHTML { public static void main(String[] args) { try { DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); dbf.setValidating(false); dbf.setNamespaceAware(false); dbf.setExpandEntityReferences(false); DocumentBuilder db = dbf.newDocumentBuilder ( ); Document doc = db.parse ( new File ( "test2.html" ) ); String newinfo = "some text"; Element root = doc.getDocumentElement ( ); // NodeList list = doc.getElementsByTagName ( "head" ); System.out.println ( root.getNodeName ( ) ); NodeList list = root.getChildNodes ( ); StringBuffer sb = new StringBuffer(); for ( int i = 0; i < list.getLength ( ); i++ ) { if ( list.item ( i ).getNodeName ( ).equals ( "head" ) ) { list.item ( i ).setTextContent ( newinfo ); } } XMLSerializer serializer = new XMLSerializer ( ); serializer.setOutputCharStream ( new java.io.FileWriter ( "test2.html" ) ); serializer.serialize ( doc ); } catch (Exception e) { e.printStackTrace(); } } }

I'm not sure that this is the way to go. Your app is supposed to insert some text/HTML between the <HEAD> and </HEAD> tags.
XML is much more precise/regulated than HTML. I would think you'd find HTML pages that would fail the XML parsing.

I'd vote for doing the scanning your self with indexOf() etc to find the <HEAD> tag and add your stuff and then copy the rest of the HTML page to output.

Comment on your code:
Don't use the same name for the input and output files.
For testing add a couple of String definitions at the head of the code:
final static String inFile = "test2In.html"; // Input file
final static String outfile = "test2Out.html"; // output file

It makes it easier to see what files are involved and to change them during your testing.