java.lang.NullPointerException: Cannot invoke "java.lang.StringBuffer.toString()" because the return value of "javax.servlet.http.HttpServletRequest.getRequestURL()" is null
	at org.jasig.cas.client.util.CommonUtils.constructServiceUrl(CommonUtils.java:334)
	at org.jasig.cas.client.util.AbstractCasFilter.constructServiceUrl(AbstractCasFilter.java:107)
	at org.jasig.cas.client.authentication.AuthenticationFilter.doFilter(AuthenticationFilter.java:186)

    public StringBuffer getRequestURL() 
    {
        return request.getRequestURL();
    }

    public Map<String, String[]> getParameterMap() 
    {
        return request.getParameterMap();
    }

    public void setCharacterEncoding(String arg0) throws UnsupportedEncodingException 
    {
        this.setCharacterEncoding(arg0);
    }

    public long getContentLengthLong()
    {
        return request.getContentLengthLong();
    }

    public int getRemotePort()
    {
        return request.getRemotePort();
    }

    public String getLocalName()
    {
        return request.getLocalName();
    }

    public String getLocalAddr()
    {
        return request.getLocalAddr();
    }

    public int getLocalPort()
    {
        return request.getLocalPort();
    }

    public ServletContext getServletContext()
    {
        return request.getServletContext();
    }

    public AsyncContext startAsync() throws IllegalStateException
    {
        return request.startAsync();
    }

    public AsyncContext startAsync(ServletRequest servletRequest, ServletResponse servletResponse) throws IllegalStateException
    {
        return request.startAsync(servletRequest, servletResponse);
    }

    public boolean isAsyncStarted()
    {
        return request.isAsyncStarted();
    }

    public boolean isAsyncSupported()
    {
        return request.isAsyncSupported();
    }

    public AsyncContext getAsyncContext()
    {
        return request.getAsyncContext();
    }

    public DispatcherType getDispatcherType()
    {
        return request.getDispatcherType();
    }

    public String changeSessionId()
    {
        return request.changeSessionId();
    }

    public boolean authenticate(HttpServletResponse response) throws IOException, ServletException
    {
        return request.authenticate(response);
    }

    public void login(String username, String password) throws ServletException
    {
        request.login(username, password);
    }

    public void logout() throws ServletException
    {
        request.logout();
    }

    public Collection<javax.servlet.http.Part> getParts() throws IOException, ServletException
    {
        return request.getParts();
    }

    public javax.servlet.http.Part getPart(String name) throws IOException, ServletException
    {
        return request.getPart(name);
    }

    public <T extends HttpUpgradeHandler> T upgrade(Class<T> handlerClass) throws IOException, ServletException
    {
        return request.upgrade(handlerClass);
    }