I've bumped into consistent hashing a couple of times lately. The paper that introduced the idea (Consistent Hashing and Random Trees: Distributed Caching Protocols for Relieving Hot Spots on the World Wide Web by David Karger et al) appeared ten years ago, although recently it seems the idea has quietly been finding its way into more and more services, from Amazon's Dynamo to memcached (courtesy of Last.fm). So what is consistent hashing and why should you care?... more »

Recently I was writing an annotation processor that would generate a persistence.xml file when I compile my JPA entity classes. If you are a Java Persistence API user, then you may actually be interested in that annotation processor. OK, enough of shameless self promotion. Coming to the issue I want to discuss in this blog... While writing the annotation processor, certain things did not happen as per my expectation. I will share them with you so that you won't waste time as I did. All those issues are generic in nature.... more »

It is now possible to configure Spring's dependency injection with annotations. This means that annotations can be used in Spring to mark fields, methods and classes that need dependency injection. Spring also supports auto-wiring of the bean dependencies, that is, resolving the collaborating beans by inspecting the contents of the BeanFactory. Now there are annotations that can be used to indicate fields that are to be auto-wired. Furthermore, auto-detection of annotated components in the classpath is also supported now. When these capabilities are combined, the amount of configuration and dependency mapping in the Spring configuration files is reduced drastically.... more »

Inserting variables into templates and then generating files from them, via Ant, is not new. Groovy has support for this too. How does it compare to the alternatives?... more »

In my neverending quest to find the best JVM settings for running Eclipse I've been pouring over talks and papers given by Sun engineers and trying different things. Here are the best options that I've found so far for my 2-processor Windows machine running JDK5.0 and Eclipse3.1: ... more »

At the weekend I managed to get some free time away from working on our next release to look at a recent benchmark that compared the performance of Google Guice 1.0 with Spring 2.5. The benchmark referred to in the article as a modified version of Crazy Bob’s “Semi Useless” Benchmark is interesting not in terms of the results but in the analysis of the results and test construction. After reviewing the findings and benchmark code I thought it would be a good idea to instrument particular parts in the code with our Probes resource metering framework to better understand some peculiarities reported and to show how I use JXInsight Probes myself.... more »

Adobe FlexBuilder is a set of plug-ins built on the Eclipse Platform which offers development tools around the Flex framework. In this short article, Renaud Denis shows you how to install FlesBuilder, and get up and running quickly.... more »

This tutorial discusses the concepts of REST and the Atom Publishing Protocol (APP) and shows how they apply to services. It also shows how to use Java technology to implement REST/APP-based services.... more »

Web 2.0 applications developed using standard Java Platform, Enterprise Edition 5 (Java EE)-based approaches face serious performance and scalability problems. The reason is that many principles that underlie the Java EE platform's design especially, the use of synchronous APIs don't apply to the requirements of Web 2.0 solutions. This article explains the disparity between the Java EE and Web 2.0 approaches, explores the benefits of asynchronous designs, and evaluates some solutions for developing asynchronous Web applications with the Java platform.... more »

Installation guide for the Groovy and Gant Toolset... more »