servlets

问题 Question How can you programmatically determine when Tomcat has completed startup? I mean programmatically from within a WAR file running on Tomcat, most likely via a Servlet that can tap into container info if possible? Background The Catalina log entry that you normally see after a WAR has fully deployed would be equal to what I'm looking for. I have a constraint that makes parsing the logs undesirable. But the data that goes to Catalina.out is precisely what I'm looking for. I'm trying to

问题 I have a servlet which calls a jsp page. In the servlet I am retrieving the username provided at the login correctly. But after setting the same in session, when i access the called jsp page, its returning null. Servlet Code: public class AdminServlet extends HttpServlet { /** * */ private static final long serialVersionUID = -4244742541587179390L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String userName = request

问题 I am trying to understand how exactly scope attribute in jsp:useBean JSP action tag works. In my understanding scope is used to indicate where the bean is located (request,session,application etc.), but after some testing I came across an interesting situation where it's not the case, please consider the following JSP code (I am using scriplets here just for the sake of simplicity): <%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1" import=

问题 I am trying to understand how exactly scope attribute in jsp:useBean JSP action tag works. In my understanding scope is used to indicate where the bean is located (request,session,application etc.), but after some testing I came across an interesting situation where it's not the case, please consider the following JSP code (I am using scriplets here just for the sake of simplicity): <%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1" import=

问题 I feel like this should be easy. I have an app where all I am trying to do is have a form page (index.jsp) that calls a servlet (CheckInfo.java) which sets a new header (myHeader) and redirects the user to another page (redirect.jsp). All of these files are on the same server. The index.jsp is sending the request just fine and CheckInfo is processing and redirecting, but myHeader is not showing up on redirect.jsp. I've read several posts talking about response.sendRedirect sends a 302 which

问题 I am developing a application in JSP/Servlet using MVC. In this application I want to load index.jsp as welcome page and this page retrieves the data from database. I did it. Now the problem is that when index.jsp page loads it fetches data from database but it shows it on browser as plain text and my CSS is not working for it. I know that during translation phase JSP is converted into servlet and after processing it send output to browser so during that we have to write the relative path of

问题 I have a problem with Tomcat, it stopped working. I installed Tomcat 3 weeks ago and I have made more than 50 web dynamic projects, maven projects and everythings worked great. And today Tomcat stopped working. For example I make a project in Eclipse and when I try to run it I get this error: Server Tomcat v9.0 Server at localhost failed to start. I can start Tomcat from Windows services, and I can open http://localhost:8080/ page in browser, but I can't start Tomcat in eclipse. Not just for

问题 I have a problem with Tomcat, it stopped working. I installed Tomcat 3 weeks ago and I have made more than 50 web dynamic projects, maven projects and everythings worked great. And today Tomcat stopped working. For example I make a project in Eclipse and when I try to run it I get this error: Server Tomcat v9.0 Server at localhost failed to start. I can start Tomcat from Windows services, and I can open http://localhost:8080/ page in browser, but I can't start Tomcat in eclipse. Not just for

问题 Im doing a small test on suspending a asynch request using jersey but im getting an error. Let me show you what im trying to do and by the way the server is up and running just this request is failing: Path("/json/metallica") public class JSONService { @GET @Path("/test") @Produces(MediaType.APPLICATION_JSON) public void getAsynchHealthyTracks(@Suspended AsyncResponse asyncResponse){ HealthService.getInstance().getHealththyTracks(asyncResponse); } } when i call this from my local host on

问题 In tomcat for a certain url, I want to skip all the filters and execute a servlet and I thought placing the servlet before the filter will to as I expected but still the filters behind the servlet mappings are executing. Am I doing anything wrong? For instance, this is my web.xml <servlet> <servlet-name>APIRedirection</servlet-name> <servlet-class>com.test.APIRedirection</servlet-class> </servlet> <servlet-mapping> <servlet-name>APIRedirection</servlet-name> <url-pattern>/abc/*</url-pattern>