Technowobble

After having some struggle with getting filters to integrate well with my Spring context, I decided to write down a small tutorial for it... To begin with, filters are defined in web.xml and are therefore not automatically part of the Spring application context, which is normally set up using the DispatcherServlet. A good way to abstract away all this is to use the DelegatingFilterProxy, which is a Spring utility class that acts as a filter, but will delegate the doFilter-method to a Spring-managed bean - normally a class extending GenericFilterBean. As a filter is defined in web.xml and looks for the bean defined in the Spring context in applicationContext.xml, it's not really the set up that I want. Filters are part of a web application and should have access to what's usually defined in webmvc-config.xml, as part of the DispatcherServlet set up. To be able to use, e.g. request scoped beans in applicationContext.xml, you need to defined them as proxied objects in order to hav...

A quick note on something that's been bugging me while using SpringSource STS with the GWT-plugin on my MacBook Pro... Sometimes, when shutting down the internal devmode server I get an error dialog saying it wasn't able to shut down the process fully (even though it looks shut down in the console window). When starting it again, it reports port 9997 to be in use already - and consequently fails to start up again. I haven't found a way to find the process within SpringSource STS, even though there are probably several ways of doing it (which I do not know about). Anyhow - I solved it using the " lsof " package (List Open Files). To find the PID of the process using port 9997, type "lsof -i :9997" in a Terminal window. A simple "kill -9 &ltpid&gt" will take care of the rest. I'm not sure if this happens on other platforms etc, but at least, now you know how to handle it if it hits you!

I've read several forum entries trying to explain how to style GWT TabLayoutPanels, and there seems to be several ways to do it. The three most common ways are to: 1) Edit the standard.css-file and update the .gwt-TabLayoutPanel, .gwt-TabLayoutPanelTabs, .gwt-TabLayoutPanelTab, .gwt-TabLayoutPanelTabInner and .gwt-TabLayoutPanelContent. 2) Override the styles by putting your own css-file as part of html hostpage. 3) Override the styles in the ui-binder file using the @external keyword. None of them really fit my needs... I want to be able to style indidividual tabs, including nesting tabs within tabs (with different styling). The methods above changes the globally set stylenames, and applies to all tabs being used in you application. What I'm looking for is to style the tabs using defined styles in the ui-binder file. This way, the styles will be obfuscated and possible to apply within it's own namespace - hence only applied to individual tabs using that namespace. ...

I decided to give SmartGWT a run, and specifically the RestDataSource functionality using Jersey. To make things easier, I'm using Spring Roo to set up my project and scaffold much of the boilerplate code, configurations etc. My approach is to have my domain objects exposed as RESTful web services and create a matching SmartGWT DataSource in order to show them in a GUI. Let's get started, shall we? First of all, you'll need Spring Roo (unless you just download the project source code and want to run it directly). I'm using the following Roo script to start things off: project --topLevelPackage com.technowobble persistence setup --provider HIBERNATE --database HYPERSONIC_IN_MEMORY entity --class ~.domain.Message field string --fieldName value controller class --class ~.ws.MessageResource --preferredMapping rest dependency add --groupId com.sun.jersey --artifactId jersey-server --version 1.3 dependency add --groupId com.sun.jersey.contribs --artifactId jersey-s...

In this post I'll combine the GWT and Spring Security integration from http://technowobble.blogspot.com/2010/05/gwt-and-spring-security.html and the Open-ID using Spring Security from http://technowobble.blogspot.com/2010/06/using-spring-securitys-openid.html . I'm assuming you've read them before reading further... :) I was also inspired by http://www.sociallipstick.com/?p=86 and http://code.google.com/p/dyuproject/wiki/OpenidLoginWithoutLeavingPage to get this working with a pop-up as my sample application is based on GWT - hence, I don't want to direct the user to another page and loose the application state etc. I'm also showing how to exchange Open-ID attributes with e.g. Google. As with the previous blogposts, the sample application is runnable on Google App Engine. With no further ado, this is basically what is needed to add Open-ID support to my previous sample application: From my second post, add Openid4javaFetcher, MyHttpCacheProvider and OpenI...

The goal with this exercise is to have a running example of an OpenID login on a simple Spring application, using Google as the OpenID Provider. Note that the application will be running on Google App Engine and that Spring Roo is only used for simplicity of creating the project files. Any Spring-based application could use the same implementation. First of all, create a simple project using Spring Roo (or any equivalent framework), including the default security setup: project --topLevelPackage com.technowobble persistence setup --provider DATANUCLEUS --database GOOGLE_APP_ENGINE entity --class ~.domain.MyEntity field string --fieldName name controller all --package com.technowobble.controller security setup This setup only provides us with a form-login, which is not what we wanted. So what about OpenID? Well, if it wasn't for Google App Engine, I would happily have added an <openid-login>-tag to applicationContext-security.xml, but things are never that easy, are the...

So I started looking into Roo the other day. Seems like a nice tool (once it matures a little more). Anyway - I wanted to create a custom module in addition to the two being generated when adding GWT-support to the project. Not as easy as I thought, mainly because I hadn't seen the Url Rewrite Filter before. I ended up with a 404, no matter what I did, and couldn't figure out why. Frustration! After reading up on the url rewrite stuff, I was ready to give it another try. Let's create a module called Application, based on the standard sample application you'll get using the GWT wizard in Eclipse. First of all, create the Roo project using the following instructions: project --topLevelPackage com.technowobble persistence setup --provider HIBERNATE --database HYPERSONIC_IN_MEMORY entity --class com.technowobble.domain.MyEntity gwt setup (The "gwt setup" setup command generates some code that will not compile unless there's a persistence setup and at lea...