Convert a String to w3c.dom.Element: XMLParseException:Start of root element expected

I found the following piece of code from a blog, when running it I get an exception

XMLParseException:Start of root element expected. at 9th line.

Can any one explain why I get the Exception and suggest any other way for converting String to an element?

String s = "Hello DOM Parser";
java.io.InputStream sbis = new java.io.StringBufferInputStream(s);
javax.xml.parsers.DocumentBuilderFactory b = javax.xml.parsers.DocumentBuilderFactory.newInstance();
b.setNamespaceAware(false);
org.w3c.dom.Document doc = null;
javax.xml.parsers.DocumentBuilder db = null;
db = b.newDocumentBuilder();
doc = db.parse(sbis);     

org.w3c.dom.Element e = doc.getDocumentElemen开发者_Go百科t();

To create a DOM Element with a custom tag (which I assume is what you want, but can't be sure), you can use the following approach:

String customTag = "HelloDOMParser";

Document doc = documentBuilder.newDocument();       

String fullName = nameSpacePrefix + ":" + customTag;

Element customElement = document.createElementNS(namespaceUri, fullName);

doc.appendChild(customElement);

I am assuming you know the namespace URI and your prefix (if any). If you don't use namespaces, just use the createElement() method instead.

Like said in the comment, "Hello DOM Parser" is not a XML element. And so the parser doesn't know what to do with it. I don't know what kind document you are building, but if you want HTML you can embed the text in a html tag for example;

<div>Hello DOM Parser</div>
<span>Hello DOM Parser</span>

if you are building XML, you can embed the text in any random html tag;

<mytag>Hello DOM Parser</mytag>

Some explanation on DOM; http://www.w3.org/DOM

To answer your question, to convert a String to a w3c Element, you can use createElement;

Element hello = document.createElement("hello");          
hello.appendChild(document.createTextNode("Hello DOM Parser"));

This results in;

<hello>Hello DOM Parser</hello>

The parse method of DocumentBuilder accept the input stream which contains the xml content. The following change will work for you:

String s = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<root><elem1>Java</elem1></root>";

Try to avoid using the deprecated classes such as StringBufferInputStream. You can refer to the document below to know more about Java XML parsing.

http://www.java-samples.com/showtutorial.php?tutorialid=152