Must-Know URL Hash Techniques for AJAX Applications

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.

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Effective and Efficient Techniques for a Rule-Based Test-Data Generator

This part explains some of the sophisticated software technology that is working behind the scenes in our rule-based test-data generator for form-centric applications. You will see that a simple enumeration of all possible ways to fill in a form is likely doomed to run longer than the age of the universe. Therefore more efficient techniques are needed to make the seemingly impossible possible.

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How Google’s Geocoding solves Address Validation

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.

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GR8Conf: A gr8t Conference on Groovy based Technologies

On May 17th-19th, I took the opportunity to escape the daily “Java business as usual” on the GR8Conf conference in Copenhagen, Denmark. The three days were packed with the latest information on Groovy related technologies such as Grails, Griffon, Gradle, GPars, Spock etc.

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Rapid Prototyping with Spring Roo

Spring Roo, a new contender to Grails and Ruby on Rails, provides flexible scaffolding for Spring based applications. We used Spring Roo in a web project to quickly provide working software in order to discuss features and gather feedback. This article shows how we generated an early prototype and transitioned to early development and then to production code.

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Getting the most out of LiquiBase

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.

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Non-Standard Ways of using Lucene

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.

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Why Functional Tests don’t belong in a Build Environment

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.

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Portlets with XForms in Liferay

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.

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Producing High-Quality Test Data

This part addresses the question what makes test data valuable for functional tests. You will understand the important concept of extreme and special values, and how to obtain test data that is highly compressed and also attains a high test coverage. The article also explains our novel idea for constructing a generator for such high-quality test data.

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Developers, Don’t Write Functional Tests!

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.

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Using Power Architect and Liquibase Efficiently

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.

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Form Validation with Rule Bases

A lot of our web applications contain a large number of forms with hundreds of fields and complex cross-field constraints. mgm’s quality assurance team uses rule bases and automatic form validation to verify the correctness of these apps. This blog series discusses the challenges in generating test data for this verification and explains our automated process for producing masses of test data by utilizing the rule bases.

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A Powerful Combo: Power Architect and LiquiBase

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.

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Test-driving XForms with Orbeon

In this second installment, we conclude our evaluation of XForms implementations and explain why we ultimately preferred the Orbeon engine. I walk you through a XForms sample to explain essential concepts. My team has spent quite a lot of time understanding the Orbeon architecture and I discuss our findings, including separate-deployment configuration and state handling.

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