Provided that you’re sure that you’re using Tomcat 7 or newer, the webapp’s web.xml has to be declared conform Servlet 3.0 spec in order to get Tomcat to scan and process the annotations. Otherwise Tomcat will still run in a fallback modus matching the Servlet version in web.xml. The support for servlet API annotations was … Read more
How can I change the contents of this page to something else ? Open the underlying JSP/HTML/XHTML file in a text editor. This page is identified by <welcome-file> entry in web.xml. If it’s e.g. <welcome-file>index.jsp</welcome-file>, then you need to open /index.jsp file in your project’s web content in the IDE builtin text editor. Or, at … Read more
It’s not supported by Servlet API to have the URL pattern wildcard * in middle of the mapping. It only allows the wildcard * in the end of the mapping like so /prefix/* or in the start of the mapping like so *.suffix. With the standard allowed URL pattern syntax your best bet is to … Read more
You need to properly handle exceptions. You should not only print them but really throw them. Replace } catch (Exception e) { e.printStackTrace(); // Or System.out.println(e); } by } catch (Exception e) { throw new ServletException(“Login failed”, e); } With this change, you will now get a normal error page with a complete stacktrace about … Read more
try this: public static String getClientIpAddr(HttpServletRequest request) { String ip = request.getHeader(“X-Forwarded-For”); if (ip == null || ip.length() == 0 || “unknown”.equalsIgnoreCase(ip)) { ip = request.getHeader(“Proxy-Client-IP”); } if (ip == null || ip.length() == 0 || “unknown”.equalsIgnoreCase(ip)) { ip = request.getHeader(“WL-Proxy-Client-IP”); } if (ip == null || ip.length() == 0 || “unknown”.equalsIgnoreCase(ip)) { ip = … Read more
Never use relative local disk file system paths in a Java EE web application such as new File(“filename.xml”). For an in depth explanation, see also getResourceAsStream() vs FileInputStream. Never use getRealPath() with the purpose to obtain a location to write files. For an in depth explanation, see also What does servletcontext.getRealPath(“/”) mean and when should … Read more
A common misunderstanding among starters is that they think that the call of a forward(), sendRedirect(), or sendError() would magically exit and “jump” out of the method block, hereby ignoring the remnant of the code. For example: protected void doXxx() { if (someCondition) { sendRedirect(); } forward(); // This is STILL invoked when someCondition is … Read more
None of both is the better approach. Servlets are intended to listen on HTTP events (HTTP requests), not on deployment events (startup/shutdown). CDI/EJB unavailable? Use ServletContextListener @WebListener public class Config implements ServletContextListener { public void contextInitialized(ServletContextEvent event) { // Do stuff during webapp’s startup. } public void contextDestroyed(ServletContextEvent event) { // Do stuff during webapp’s … Read more
<url-pattern>/*</url-pattern> The /* on a servlet overrides all other servlets, including all servlets provided by the servletcontainer such as the default servlet and the JSP servlet. Whatever request you fire, it will end up in that servlet. This is thus a bad URL pattern for servlets. Usually, you’d like to use /* on a Filter … Read more
It’s your choice. There are basically three ways in a Java web application archive (WAR): 1. Put it in classpath So that you can load it by ClassLoader#getResourceAsStream() with a classpath-relative path: ClassLoader classLoader = Thread.currentThread().getContextClassLoader(); InputStream input = classLoader.getResourceAsStream(“foo.properties”); // … Properties properties = new Properties(); properties.load(input); Here foo.properties is supposed to be placed … Read more