servlets

问题 How do I get the previous page URL from request using a servlet. For example, I'm from the index.html and I submitted a form from index, how do I get the index.html URL and use it in a servlet? request.getRequestURL() getRequestURL doesn't work since it only returns the URL of the servlet. 回答1: Write in your Servlet the following code String url = request.getHeader("referer"); This worked in my case.Hope it works for you as well 回答2: I think request.getAttribute("javax.servlet.forward.request

问题 How do I know when my Vaadin 7 web app first starting/launching, so I can do some initial set-up work? Likewise, how do I know when my web app is ending, getting shutdown/exiting? 回答1: ServletContextListener Vaadin is built on top of Java Servlet technology. A “context” is the technical term for your web app in Servlet terms. So the answer here is not Vaadin-specific, it applies to any Servlet -- and at the end of the day, Vaadin is just one big Servlet. Since Servlet spec version 2.3, a

问题 How do I know when my Vaadin 7 web app first starting/launching, so I can do some initial set-up work? Likewise, how do I know when my web app is ending, getting shutdown/exiting? 回答1: ServletContextListener Vaadin is built on top of Java Servlet technology. A “context” is the technical term for your web app in Servlet terms. So the answer here is not Vaadin-specific, it applies to any Servlet -- and at the end of the day, Vaadin is just one big Servlet. Since Servlet spec version 2.3, a

问题 I tried inserting data for selecting product class idcat class category with a combo but nothing any ideas please -CLASSES public class Categoria { private int idcat; private String name; private String descrip; } public class Producto { private int producto; private int idcategoria; private String nombre; private String descrip; } -DAO CLASS CategoriaDAO public Collection listarIdCat() throws DAOExcepcion{ Collection<Categoria> c=new ArrayList<Categoria>(); String query="SELECT id_categoria

问题 In Servlet 3.0 specification, two servlets have different max file size can be created and worked fine. @WebServlet(urlPatterns = { "/ureupload1" }) // 10MB @MultipartConfig(maxFileSize = 1024 * 1024 * 10) public class UploadServlet1 extends HttpServlet { and @WebServlet(urlPatterns = { "/ureupload2" }) // 30MB @MultipartConfig(maxFileSize = 1024 * 1024 * 30) public class UploadServlet2 extends HttpServlet { If using Spring Boot Controller, @MultipartConfig seems to be not worked. @Controller

问题 I need to implement file download .I don't want give any server side file urls to download directly .I created a servlet which will open the file and write it to stream of response.Now coming to front gwt i have onResponseReceived(Request request, Response response) which will be called on receiving the response .Now how to proceed further? .My operation required is ,file in stream should be downloaded to client computer. can one help me regarding this ? 回答1: Did you try Window.open

问题 Although lots of people have asked this question and I have gone through many of them but unable to fix my issue. I think its simple but unfortunately I am stuck here. I am able to hit my listener externally but not getting from IPN simulator. Getting the following error any help is highly appreicated. cheers! 回答1: Using a "raw" IP address in the target URL appears to be prevented by PayPal's IPN simulator; I've been testing it out and it seems that the simulator will only send a request if

问题 My code is from server jsp accessing another jsp which is in clients machine and this is perfectly communicates between client machines and server with in my office network without any issue. But the same code when my server jsp is in outside office(another network) and client machines in my network, am getting connection timeout exception in server logs. And when I connect to client machine through ajax call, i am able to get response form client.my code is below. Java code in server jsp:

问题 App Info: Grails Version: 3.1.8 Groovy Version: 2.4.6 JVM Version: 1.8.0_60 I'm running grails package to get runnable archives however I come across the following error: Could not resolve all dependencies for configuration ':gspCompile'. Could not resolve javax.servlet:javax.servlet-api:3.1.0. Required by: app:app:0.1 Could not resolve javax.servlet:javax.servlet-api:3.1.0. Could not get resource 'https://repo.grails.org/grails/core/javax/servlet/javax.servlet-api/3.1.0/javax.servlet-api-3.1

问题 This question already has answers here : How to retrieve and display images from a database in a JSP page? (5 answers) Closed 3 years ago . I want to retrieve image from database which is stored as a blob and this image is a profile image of employee so with image some other details will come like name,designation and all so i am passing servlet path and value in employeedetail.jsp and it is going to that servlet and everything is correct like query , parameter but finally on employeedetail