There are two steps to create a custom function for JSP: Declare the function in the TLD: <?xml version="1.0" encoding="UTF-8" ?> <taglib... Implement the function (must be static): package com.example; public class UrlTransl... To use the function: <%@ taglib uri="http://www.example.com/jsp/tags" p...

Spring MVC 3.1 can send either JSON or HTML response on the same URL, depending on the type of response requested. With this mechanism, a page can be sent when directly requested from a link, but a JSON response can be sent in response to an AJAX request. This is the controller code: package com.example; import java.util.Map; ... In the above example, JSON response will be sent when the HTTP request contains header "Accept: application/json". HTML response will be sent then the header is "Accept: */*", or "Accept: text/html", or anything else. You can add a limitation that the HTML response does not produce "application/json". But then the question is which response will be sent when the HTTP header is "Accept: */*"? Both methods will...

After a user resets a password, I want to force the user to change the password before she gets access to secured content. This is usually done with a servlet filter. But with Spring MVC, you can also use a HandlerInterceptor . According to Spring JavaDoc: HandlerInterceptor is basically similar to a Servlet 2.3 Filter, but in contrast to the latter it just allows custom pre-processing with the option of prohibiting the execution of the handler itself, and custom post-processing. Filters are more powerful, for example they allow for exchanging the request and response objects that are handed down the chain. Note that a filter gets configured in web.xml, a HandlerInterceptor in the application context. As a basic guideline, fine-grained handler-related preprocessing tasks are candidates...

The landing page after login can be configured with the default-target-url attribute of form-login . If a user was redirected to the login form after requesting a restricted URL, she's redirected to the original requested page after successful login. An easy configuration looks like this: <beans:beans xmlns="http://www.springframework.org... But there are times that you want to do more initialization after login (such as loading user data), or apply more complex logic before redirecting. This is where the authentication-success-handler-ref attribute comes into play. You create a class that implements org.springframework.security.web.authentication.AuthenticationSuccessHandler and use that as the authentication-success-handler-ref : <http entry-point-ref="authProcessFilterEn... This is a skeleton implementation: public class MyAuthenticationSuccessHandler implem...

You can customize Tomcat error page with error code: <error-page> <error-code>404</error-code> ... or Java exception type: <error-page> <exception-type>java.lang.Throwab... Either error-code or exception-type is required, but not both. There's no way to aggregate error codes, such as: <!-- This does not work! --> <error-page> ... Customizing error pages is about the only way to suppress the default stack trace in Tomcat in case of an unhandled exception.

Dojo ShrinkSafe: http://shrinksafe.dojotoolkit.org/ : command line utility written in Java, based on Rhino - JavaScript engine written in Java. Douglas Crockford's JSMIN: http://crockford.com/javascript/jsmin : command line utility written in C, can download MS-DOS exe. Dean Edwards' Packer: http://dean.edwards.name/packer/ : online tool, or .NET, Perl, PHP application. YUI Compressor: http://developer.yahoo.com/yui/compressor/ : command line utility written in Java. Google Closure Compiler : command line Java application, web application, or RESTful API. One problem is, the compressor utility may not be 100% reliable. So make sure to test the compressed script.

You can define environment variables in the Tomcat context.xml file like this: <?xml version="1.0" encoding="UTF-8"?> <Context... which is equivalent to the following in web.xml : <env-entry> <env-entry-name>varName</env-entr... In Java code, the variable can be looked up like this: // import javax.naming.Context; // import javax...

Maven is a powerful yet complex tool. When I started learning Maven, the first obstacle was, of course, its complexity. The second, was the lack of documentation that can get me off the ground quickly. This tutorial is an attempt to create a pragmatic guide that aims to get you familiar with Maven in the quickest way possible. The main theme is to get you on some hands on experience to start out and lead you through the creation of a simple Java EE project as quickly as possible. Instead of trying to give you a good read, I try to get you on the journey right away. The topics are roughly ordered by the logical sequence but you can jump around in any way...

This is a simple Hello World application with Spring 3 MVC. Like the default Apache HTTPd welcome page, it displays " It works! " when successfully deployed. The sole purpose is to show the minimum elements needed to setup Spring 3 MVC. I use Maven since it's so much easier than downloading the dependencies manually. Directory layout: ./src ./src/main ./src/main/webapp ./src/... pom.xml : <?xml version="1.0" encoding="UTF-8"?> <project... WEB-INF/web.xml : <?xml version="1.0" encoding="UTF-8"?> <web-app... WEB-INF/applicationContext.xml (empty, but needed): <?xml version="1.0" encoding="UTF-8"?> <beans x... WEB-INF/spring-servlet.xml : <?xml version="1.0" encoding="UTF-8"?> <beans x... WEB-INF/jsp/home.jsp : <!DOCTYPE html> <html> <head> <title>H... Build with: mvn clean package The resulting webapp is target/springmvc.war .

These are the minimum steps to configure Spring MVC in web.xml : Bootstrap Spring MVC by registering ContextLoaderListener : <listener> <listener-class> org.springfra... Register the DispatcherServlet : <servlet> <servlet-name>spring</servlet-name> ... Add servlet-mapping : <servlet-mapping> <servlet-name>spring</servle... Configure DispatcherServlet with WEB-INF/spring-servlet.xml , which configures WebApplicationContext specific to this servlet. <?xml version="1.0" encoding="UTF-8"?> <beans x... Optionally, use context-param in web.xml to configure the global WebApplicationContext : <!-- XmlWebApplicationContext is the default, so t... If you omit this section, you have to create file WEB-INF/applicationContext.xml , even if it's empty. This is the full web.xml : <?xml version="1.0" encoding="UTF-8"?> <web-app...