code: public String getNamespaceURI(String prefix) {
  		List<NamespaceDeclaration> nsDecls = getNamespaceDeclarations();
  		for (int i = 0; i < nsDecls.size(); i++) {
  			NamespaceDeclaration nsDecl = nsDecls.get(i);
  			if (nsDecl.prefix.equals(prefix)) {
  				return nsDecl.namespaceURI;
  			}
  		}
  		return null;
  	}
docs: /*
  Return the uri for the given prefix.
  
  (non-Javadoc)
  
  @see javax.xml.stream.XMLStreamReader#getNamespaceURI(java.lang.String)