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Evan Summers

Evan Summers lives in Cape Town and plays Java, PostgreSQL and Linux. Most interested in crypto, systems monitoring and BI right now. Past interests include Swing, and future interests include mobi web.

 

Weblogs

In a recent blog entry, I publicized my...

We consider client devices (e.g. Android) connecting to a Java server for secure networking. Say we have stringent authentication requirements, and so decide to use client-authenticated SSL...

In 2013, I was a Linux sysadmin, PostreSQL DBA, and erstwhile Java developer for a payment switching company, who was preparing for their first PCI assessment. Besides securing and virtualising...

Redis is good for prototyping, shared memory, messaging, caching and maximum performance. It might be used orthogonally and/or complementary to your SQL relational store, and/or NoSQL document...

We continue our Password Salt adventures with PBKDF2, in order to store multiple revisions of the crypto parameters, and migrate hashes on the fly.

This provides a long overdue update to "Password Hash" from the Enigma Prequels (2007), where that article neglected to add salt, which is embarassing for whoever wrote that article... which was...

We present a miniscule Millis utility class for handling intervals, in milliseconds, not least because we record timestamps as per System.currentTimeMillis, i.e the number of milliseconds since...

The Google Authenticator mobile apps implement an IETF time-based one-time-password standard. This hashes the time, with a shared secret using the HMAC-SHA1 algorithm, to generate a one-time...

Last time we introduced the trivial namesake Timestamped interface, and used the excellent ArrayDeque of Java6 to collect such things, imposing a time-based capacity and some external...

In this here second part of the "Timestamped" series, we introduce its namesake Timestamped interface, and use a Deque from Java6 to collect such things, and impose a time-based capacity for that...

We herewith begin a saga about monitoring with this series entitled "Timestamped: a trilogy in a few parts," this being the first part, where we introduce a map to count key things, and ensure we...

I enjoyed reading the Android=Java blog just now, and agree with Osvaldo's sentiments.

So we need to convert objects into XML and back again, eg. to store some data in...

Notwithstanding the fact that anyone in their right mind (which rules me out) would use Apache Velocity or FreeMarker for templating, we present a trivial templating helper class, where for...

Having blogged this hack some years ago (...

In the Gooey MvnC prequel, we advocate an MVC-type architecture for programming a Swing UI panel, using...

We gonna consider the definition and evolution of computer UI. But first, what is a computer? It's a number crunching machine that interfaces to a human being, innit. Actually, "data crud'ing" is...

In the Gooey MvnC prequel, we consider an MVC-type separation for programming a Swing UI panel, and convention...

Web 1.0, XUL, Ajax, Laszlo, Flex and Silverlight have a common approach - declare the UI view using markup (HTML or XML), and use JavaScript to handle the UI events and manipulate the UI. JavaFX/...

Rather than put our "application logic" in a "messy" view class, we create a separate "controller" class, with event handlers. We wish this controller class to be as neat and tidy as possible e.g...

Who knows why i have a dislike for symbols like ->, => and even := ?! It's pathological, i know that, and i have an obsessive-compulsive (dis)order when it comes to code, and so be it.

One site i visit every day is LXer.com which is a Linux news site. Today that took me to a
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Since i've hardly being doing anything very useful of late, i decided it's time to return to my potentially generally useful efforts of a year ago vis-a-vis "countries of the world" and publish...

So last week i started rambling about "First Class Java." Lemme continue while i wait for my clothes to dry on the line outside, whilst i prepare myself for a wedding this afternoon, which i love...

So i had this vague idea some weeks ago for some blog articles to keep myself amused if no one else. The idea is... to dream of a Java Refined. Not something totally different like JavaFX Script...

Recently i was travelling through Europe for three months without my laptop and/or its 3G wireless internet connection, sometimes cycling in the French Pyrenees, not knowing for sure if i would...

So the "personal computer" platform with its graphics, internet et al, is converging with telephony handsets, and visa versa. It's nice. I'm trying to understand how Android changes the pace of...