web

A collection of 10 posts

watermark images web Kotlin

Dynamic watermarking on the JVM

Displaying images on your website makes for an interesting problem: on one side, you want to make them publicly available; on the other, you want to protect them against undue use. The age-long method to achieve it is watermarking: A digital watermark is a kind of marker covertly embedded in a noise-tolerant signal such as audio, video or image data. It is typically used to identify ownership of the copyright of such signal. 'Watermarking' is the process of hiding digital information in a car
web HTTP cache performance

Web resource caching: Server-side

The subject of Web resource caching is as old as the World Wide Web itself. However, I’d like to offer an as-exhaustive-as-possible catalog of how one can improve performance by caching. Web resource caching can happen in two different places: client-side - on the browser and server side. In the previous post, I explained the former; this post focuses on the latter. While client-side caching works well, it has one central issue: to serve the resource locally, it must first have it in the

web HTTP cache performance

Web resource caching: Client-side

The subject of Web resource caching is as old as the World Wide Web itself. However, I’d like to offer an as-exhaustive-as-possible catalog of how one can improve performance by caching. Web resource caching can happen in two different places: client-side - on the browser and server-side. This post is dedicated to the former; the next post will focus on the latter. Caching 101 The idea behind caching is simple: if a resource is a time- or resource-consuming to compute, do it once and st
web attribute request session

Easier attribute management in Java EE

Last year, I’ve been tasked to design a course and teach it to students of the 3rd year of a higher-education school in Geneva. Though I’m a Spring fan, foundations of Spring’s Web MVC take their root in Java EE e.g. servlets and filters. For this reason, I created the course on Java EE. I started my career with Java and J2EE 1.3. By reading the documentation again, I learned a few things regarding the changes since that time. This post is dedicated to one of my findings: how

hack JavaScript web SPA

Hacking a web page's JavaScript

I recently acquired a Logitech Spotlight Presentation Remote to help me during my presentations. While some conferences propose clickers to speakers, not all of them do. And it’s quite inconvenient to be bound to the laptop to advance to the next slide when presenting, as I like moving around in general. When I received the remote, I was eager to test it, and I was happy to assert it worked on Google Slides. The root issue I went to a meetup just afterwards, and I couldn’t help no
user interface web

Quick evaluation of Twitter Bootstrap

I must admit I suck at graphical design. It’s one of the reasons that put me in the way of Flex and Vaadin in the first place: out-of-the-box, you got an application that is pleasing to the eye. Using one of these technologies is not possible (nor relevant) in all contexts, and since I’ve got a strong interest in UI, I regularly have a look at other alternatives for clean looking applications. The technology I studied this week is Twitter Bootstrap. Bootstrap is a lightweight clie
web

Critical analysis of frameworks comparison

Let me first say I was not at Devoxx 2010. Yet, I heard from Matt Raible’s Comparing JVM Web Frameworks. Like many, as I read the final results, I was very surprised that my favorite framework was not ranked first. I passed through all stages of grief, then finally came to realize the presentation itself was much more interesting than the matrix. The problem lies not in the matrix, but in the method used to create it.
session terracotta web

Managing web sessions

In the previous article, I set up a cluster of 2 Tomcat instances in order to achieve load-balacing. It also offered failover capability. However, when using this feature, the user session was lost when changing node. In this article, I will show you how this side-effect can be avoided. Reminder: the HTTP protocol is inherently disconnected (as opposed to FTP which is connected). In HTTP, the client sends a request to a server, it gets its response and that’s the end. The server cannot na
jawr jsp taglib web yslow

Decrease your pages load time

1. Generalities Web applications have several advantages over traditional client server applications: since business code comes from a unique server (forget clustering here), they are always up-to-date. Moreover, deployment of a new version is only a matter of minutes. They have one big drawback, though. Since HTML code is sent through the network, responsiveness is generally much less than that of traditional applications. The responsiveness of an interactive system describes how quickly