servlets

问题 I'm trying to set up a server-side cache properly and I'm looking for constructive criticism on the setup I have currently. The cache is loaded when the Servlet starts and never changed again, so in effect it's a read-only cache. It obviously needs to stay in memory for the lifetime of the Servlet. Here's how I have it set-up private static List<ProductData> _cache; private static ProductManager productManager; private ProductManager() { try { lookup(); } catch (Exception ex) { _cache = null;

问题 I'm trying to set up a server-side cache properly and I'm looking for constructive criticism on the setup I have currently. The cache is loaded when the Servlet starts and never changed again, so in effect it's a read-only cache. It obviously needs to stay in memory for the lifetime of the Servlet. Here's how I have it set-up private static List<ProductData> _cache; private static ProductManager productManager; private ProductManager() { try { lookup(); } catch (Exception ex) { _cache = null;

问题 I need to set max filesize for uploaded files in my servlet running on tomcat. I tried multipart config which worked on jetty, but tomcat just ignored it. It means deployment on tomcat server caused even big files can be uploaded. My configuration: <servlet> <servlet-name>myServlet</servlet-name> <servlet-class>sk.test.MyServlet</servlet-class> <multipart-config> <max-file-size>1048576</max-file-size> <max-request-size>104857600</max-request-size> </multipart-config> </servlet> I already

问题 i use the reverse engeneering in my class and get this: @Entity @Table(name = "user", catalog = "bytecode", uniqueConstraints = @UniqueConstraint(columnNames = "email")) public class User implements java.io.Serializable { private Integer id; private String email; private String password; private boolean type; Database: CREATE TABLE `bytecode`.`user` ( `id` int(11) NOT NULL AUTO_INCREMENT, `email` varchar(255) NOT NULL, `password` varchar(255) NOT NULL, `type` bit(1) NOT NULL, PRIMARY KEY (`id

问题 I'm working through the Java EE servlet tutorial and tried the mood example. I noticed the doFilter is getting called twice, once the servlet call is in the chain and the second time it isnt. I added some printlns in the TimeOfDayFilter.java and in the MoodServlet.java to show this. TimeOfDayFilter.java: ... System.out.println("TimeOfDay before"); //added chain.doFilter(req, res); System.out.println("TimeOfDay after"); //added ... MoodServlet.java: ... response.setContentType("text/html

问题 TL;DR: <load-on-startup> does not seem to be causing my Jersey web services to load on startup I’m trying to set up a simple RESTful web service that will act as a registry for the other RESTful services in the container. To do this I had planned on registering each other web service with the registry service in a static initialize block. Everything was going well until I remembered that servlets aren’t loaded until their first access. A quick web search turned up the <load-on-startup> tag

问题 This is probably a really easy question, but I actually haven't seen many search results on this. I have a very basic submit button within a form that takes some user input, and generates a downloadable file in the server's temp directory, then prompts the user to download this file, which is then disabled by this on submit: <form action="Home" method="post" onsubmit="Submit.disabled = true; return true;"> ... <input type="submit" name="Submit" value="Submit" id="Submit" /> We need it to be

问题 This is probably a really easy question, but I actually haven't seen many search results on this. I have a very basic submit button within a form that takes some user input, and generates a downloadable file in the server's temp directory, then prompts the user to download this file, which is then disabled by this on submit: <form action="Home" method="post" onsubmit="Submit.disabled = true; return true;"> ... <input type="submit" name="Submit" value="Submit" id="Submit" /> We need it to be

问题 I want to connect to database in java web application.I wrote this code in servlet and i add related jar file(ojdbc) but when i run it,it gives me this error: java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver public class DBConnection extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public DBConnection() { super(); // TODO Auto-generated constructor stub } public void service(HttpServletRequest request,

问题 I want to connect to database in java web application.I wrote this code in servlet and i add related jar file(ojdbc) but when i run it,it gives me this error: java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver public class DBConnection extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public DBConnection() { super(); // TODO Auto-generated constructor stub } public void service(HttpServletRequest request,