Regular Expressions: Splitting Pipes

It’s a common saying in IT: “I had a problem and used regular expressions to solve it. Now I’ve two problems”. We want to offer help in a series of mgm “Hacking Java Puzzler” blog entries and demonstrate how regular expressions can be useful anyway. In this first episode we will focus on splitting CSV lines.

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Building a scalable Web-based Call Center CTI Solution

My project was part of our customer’s effort to replace all of the enterprise applications with web applications based on a standardized technology stack. In this strategic move, the call center integration was a crucial step. As it turned out, the technical design of the new call center telephony solution was quite challenging. We did not only learn a lot about CTI; we also had to implement the system to be scalable and ensure that it handles more than 1000 call center agents.

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Consequences when using Mutable Fields in hashCode()

We start our new series with an informative HashSet puzzler. It’s about a bug that gave us quite a headache since its root cause was hard to identify. This subtle bug has without doubt crept into many code bases, so a detailed discussion should interest every Java coder. I will also discuss code inspection tools that detect this violation (sadly, only few). And by the way, what we learned about HashSet also makes a good topic in our job interviews.

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Using Domain Specific Languages to Implement Interactive Frontends

For many years we have dealt with the challenges that frontends with interactive forms pose w.r.t. validation, test data and quality. Describing the requirements in formal Domain Specific Languages (DSL) became the way of choice to create a specification that gives a twofold benefit: first, the customer understands it better, and secondly, the software engineers use the specification not only to implement more resilient software, but also to improve quality assurance. This new series will explain how we do it and why we think it’s the best approach.

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Ultra-Performant Dynamic Websites with Varnish

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.

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Practical Customer Participation in JIRA Workflows

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.

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Successfully Embracing JIRA in the whole Project Lifecycle

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.

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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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