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Java8 is great and adds some useful abstractions to the JDK that have found popularity in the Java community via the wonderful Guava commons library from Google. Group discussion indicates that there will be a Guava version soon that requires Java 8 and closes the gap between Guava and Java8.

Here's a few slides on some of the Spring4 and Spring Boot features that I used on a recent project that are interesting. This is not really an introduction to Spring Boot -- but just highlighting a few features. This talk was

I'm giving a talk to the local Data Science / Machine Learning meetup. The topic is a shallow tour of data science topics including tasks and methods. This is a new group and many of the attendees do not have a data science background but are interested. Therefore,

I'm working on a problem right now where I need to calculate the mean and standard deviation of a value in a streaming fashion.  That is I receive a stream of events that generate data points and I need to calculate standard deviation without retaining all of the data points in memory.  This has been covered ad nauseam in the literature -- I will

On one of my current projects we are using Cassandra and Spark Streaming to do some somewhat-close-to-real time analytics. The good folks at Datastax have built a commercial packaging (Datastax Enterprise, aka DSE) of Cassandra and Spark that allow you to get this stack up and running with relatively few headaches.

Right now I'm working on a project with a few people who have never worked in Java before. There have been times where they'll experience some problem that they can't easily figure out. They send me the stack trace and instantly I know what the problem is. I wanted a simple way to automate this.

I guess I just don't use SQL's MERGE statement enough to remember its syntax off the top of my head. When I look at the Microsoft documentation for it, I can't find just a simple example to do a single record UPSERT. When I google, I don't get any brief blog posts that show it. So

Are you using AspectJ @Transactionals and Spring? Do you have multiple SessionFactory's maybe one for an embedded database for unit testing and one for the real database for integration testing? Are you getting one of these exceptions?

I have always enjoyed digging in to the details of multi-threaded programming, and always enjoy that despite reading for years about CPU memory consistency models, wait-free and lock-free algorithms, the java memory model, java concurrency in practice, etc. etc. -- I still create multi-threaded programming bugs. It's always a wonderfully humbling experience that reminds me how complicated of a problem this is.

Most of my academic background focused on low level database research. I wrote a dynamic programming based join-order optimizer for the open-source SQLite database as project in school.

I gave a talk for our group about multi-threaded java programming for some of our junior members. I lifted a bulk of the slides from the interwebz, but

For a while, I've used the Apache Commons lang StringUtils implementation of Levenshtein distance.  It implements a few well known tricks to use less memory by only hanging on to two arrays instead of allocating a huge n x m table for the memoisation table.  It also

Every week our team gets together on friday afternoons and have a presentation. The presenter rotates each week, and the topic can be programming language related, cool new libraries, theoretical -- or whatever related to our work.

We brought on some new team members recently and I couldn't find a good intro to Spring that went through the motivation of why one might use Spring.  Thus, I created this presentation.  Don't know if anyone else will find it valuable:

Among non-technologists, I think there is a common belief -- a wishful thought-- that building software is like any manufacturing process. You just need to design the process, and then get the widgets on the assembly line to execute the process-- and viola! If a widget quits, you just buy a new widget at

I have been an Eclipse fan-boy for the last 7 years. I have participated on a number of open source Eclipse plugin projects. I have evangelized it to others. I also have a personal connection to it as my father was one of the project principles when it was still an IBM project.

Just upgraded one of our projects to Spring 3.1.1 and Hibernate 4.1.1 today and ran into a small problem that ate up some time.

Symptom:

It appeared as if all of my hibernate <property>'s in hibernate.cfg.xml were suddenly not being picked up -- they were just silently being ignored.

Databases aren't queues.

And despite the ubiquitous presence of queuing technology out there (ActiveMQ, MSMQ, MSSQL Service Broker, Oracle Advanced Queuing) there are plenty of times when we ask our relational brethren to pretend to be queues.  This is the story of one such folly, and along the way, we'll delve into some interesting sub-plots of deadlocks,

Today I received a question from someone about the nature of the INCLUDE feature when creating a non-clustered (secondary) index on a table. My response was a bit long, and I haven't posted in a while -- ergo blogpost! Here's the question:

I have a mixed background: doing C#/.NET for ~4 years then switching to Java (switched jobs). I have been in the Java enterprise ecosystem for the last 4 years. I do mostly Java, but enjoy doing a little C# every now and again. C# is really a nice language. Shame its in such a horrible Microsoft-centric ecosystem.