This blog is a place to meet our experts. We share technical knowhow and lessons learned from software projects, and discuss clever solutions for real-world problems.
I recently had the opportunity to test and tune the performance of several shop and portal applications built with Java and running on the Sun/Oracle JVM, among them some of the most visited in Germany. In many cases garbage collection is a key aspect of Java server performance. In the following article we take a look at the state-of-the-art advanced GC algorithms and important tuning options and compare them for diverse real-world scenarios.
Do you also spend sleepless nights because you have saved the passwords of your users in clear text or near-clear text (MD5)? We will show you a simple method how you can smoothly migrate your password database to a much more secure format. The transition is transparent to the users and instant, i.e. as soon as you have implemented the process, your passwords are safe. If you still store your passwords in an insecure format, you should convert them to a secure format as soon as possible. Do it now!
This article describes how we configured and used the Varnish web cache for the popular German online shop www.lidl.de. Varnish gave us a tremendous performance boost. With this new caching setup, we easily achieve request rates of several thousand pages per second, which are quite common during marketing campaigns like special offers.
This second part of our blog series continues with the topic of direct involvement of customers and gives some practical examples of when, where and how to introduce and include your customer into JIRA. We will then discuss two of mgm’s proven real-world workflows and use them as case studies about appropriate modes for successful customer participation. You will also learn about our recommended ways of keeping the complexity of huge JIRA projects from the customer.
This two-part series shows how JIRA can be used for other things than just bug tracking and presents mgm’s experiences with embracing JIRA in nearly all parts of traditional and agile project lifecycles, resulting in a number of customized, optimized JIRA workflows and processes. In this first part, I will give you an overview of challenges we faced over the years and how we adapted JIRA to meet them. You will get a taste of the vast variety of uses we have found for JIRA and understand why we decided to use only one tool instead of many.
Dr. Christian Winkler,
26.10.2011 |
9 Comments 
By coding the page state into the URL, even single-page web applications can support deep bookmarks and the browser’s back button. The most accepted approach is to utilize the location hash, i.e. the local part of the URL. This article explains this technique and what pitfalls you should be aware of, based on my team’s experience from building an AJAX interface for Solr. You will also learn about the HTML5 History API, which is a second, more modern technique.
For the e-commerce business, it is very important to have a valid and correct address base. Sending packages to incorrect addresses causes significant losses, since packages are not delivered and sent back. In the case of the Kickz online shop, we faced exactly this problem. Thus, we thought about how to improve and force users to enter correct addresses. Learn how we used Google’s Geocoding service to solve this problem.
This last part of the series, we focus on successful database schema evolution with LiquiBase. You will learn about LiquiBase features that we find most useful in our projects. This article also gives a roundup of our best practices and tips, like how to include custom SQL and stored procedures and how to use LiquiBase with different DBMS products.
For our recent online shop project, we required a full-text, multi-criteria product search. Lucene, the popular Java search engine, is an ideal candidate for this functionality. But in order to meet the high performance requirement, we had to extend its usage beyond standard full-text search. This posting describes our solution including index switching and using Lucene as a simple NoSQL database.
The previous part discussed why a unit test for a class should be written by the developer of that class, and why a functional test should be created by an independent tester. This posting argues that functional tests should not be part of the build process of the product, but instead should be developed and executed separately. For this, I give guidelines for setting up an independent validation system.
This posting discusses how we integrated an web application with XForms as one of the main view technologies into a Liferay portal. We were using the Orbeon 3.8 XForms engine, which was introduced in the previous part of this series, and Spring Portlet MVC. Since we were facing quite a few problems and issues regarding Orbeon and Liferay, I go to great length discribing our working solution.
Over the past few years I have noticed that the distinction between functional tests and unit tests has blurred in a lot of projects. I think that using the features of modern testing frameworks like JUnit and TestNG to push functional tests into unit tests is the wrong approach, because it shifts the focus of the test from the test perspective to the development perspective. In this blog post, I explain in detail how I have come to this conclusion.
In the first part of this blog series, I have motivated the combined usage of SQL Power Architect and LiquiBase. This part takes a closer look on how to actually work with our tool-chain. My colleague Thomas Kellerer, who is also involved in the Power Architect development, provides some great tips and tricks.
Using the open source tools Power Architect, LiquiBase and Subversion, we have built an integrated tool chain for data modeling and database script management for various DBMS products. The evolution of the data model is guided by a change process on top of the tool chain. In this first part of the series, I introduce the tool-chain and discuss its benefits such as portability, reuse, and generated documentation.
Serious on-site optimization begins with the head tags of your HTML documents. For example, up to 150 characters from the description are displayed on the search result pages. This article gives a concrete guideline for writing the HTML head section. You will also learn the meaning of important and even some mysterious meta tags, e.g. GEO values, and find out what is now deprecated.
