How to get servlet mapping by servlet name in tomcat 6?

Question

In servlet 3.0 & tomcat 8 , we can get servlet mapping by the servlet name as following:

request.getServletContext().getServletRegistration(servletName).getMappings()

But in tomcat6, getServletRegistration is not exist so how to get the servlet's url mapping by the servlet name?

Answer 1

Since no one reply so I answer my question. I find a way to do that:

Since tomcat6 isn't support dynamic add servlet and annotation for endpoint, so I find a workaround method that direct read the servlet information form web.xml in the listener:

public class SomeListener implements ServletContextListener {

    public static ServletContext context;

    @Override
    public void contextInitialized(ServletContextEvent sce) {
        context = sce.getServletContext();
        Map<String, String> valuesMap = new HashMap<String , String>();
        try {
            String fileName = context.getRealPath("/")+"/WEB-INF/web.xml";
            FileInputStream fileInputStream = new FileInputStream(fileName);
            DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
            DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
            Document document = docBuilder.parse(fileInputStream);
            XPathFactory factory = XPathFactory.newInstance();
            XPath xpath = factory.newXPath();
            NodeList nodeList = (NodeList)xpath.compile("/web-app/servlet-mapping").evaluate(document, XPathConstants.NODESET);
            for (int index = 0; index < nodeList.getLength(); index++) {
                Node node = nodeList.item(index);
                if( node instanceof Element) {
                    Element docElement = (Element) node;
                    Node cell = docElement.getElementsByTagName("servlet-name").item(0);
                    Node cell2 = docElement.getElementsByTagName("url-pattern").item(0);
                    if ( cell != null && cell2 != null ){
                        valuesMap.put(cell.getTextContent() , cell2.getTextContent());
                    }
                }
            }
            context.setAttribute("servletMapping" , valuesMap );
            System.out.println("init the servlet map." );
        }catch (Exception exception){
            exception.printStackTrace();
        }
    }


    @Override
    public void contextDestroyed(ServletContextEvent sce) {
        context = null;
    }

}

And just get the mapping form context:

    public static String getMapping( HttpServletRequest request , String servletName){
        return ((Map<String, String>)request.getSession().getServletContext().getAttribute("servletMapping")).get(servletName);
    }