Java

Our development team wanted to get notified as soon as something goes wrong in our production system, a critical Java web application serving thousands of customers daily. The idea was to let it send us an email when there are too many errors, indicating usually a problem with a database, an external web service, or something really bad with the ...

Many RDBMS support the concept of “routines”, usually calling them procedures and/or functions. These concepts have been around in programming languages for a while, also outside of databases. Famous languages distinguishing procedures from functions are: Ada BASIC Pascal etc… The general distinction between (stored) procedures and (stored) functions can be summarized like this: Procedures: Are called using JDBC CallableStatement Have ...

This post explores the new Java caching standard: javax.cache. How it Fits into the Java Ecosystem This standard is being developed by JSR107, of which the author is co-spec lead. JSR107 is included in Java EE 7, being developed by JSR342. Java EE 7 is due to be finalised at the end of 2012. But in the meantime javax.cache will ...

OVERVIEW To start with it is natural to assume that static fields have a special life cycle and live for the life of the application. You could assume that they live is a special place in memory like the start of memory in C or in the perm gen with the class meta information. However, it may be surprising to ...

Good functional testing is one of the most difficult tasks for web application developers and their teams. It is a challenge to develop tests that are cheap to maintain and yet provide good test coverage, which helps reduce QA costs and increase quality. Both Selenium and WebDriver (which is essentially now the successor to Selenium) provide a good way to ...

Looking in the internet for a way to test my Spring 3 application, I found many articles that describe how to test your application by using JUnit. Most of them are incomplete examples that do not really work. With this article I will try to fill this gap and write a concise yet simple article on how to test a ...

On a pet project recently I set out to build automated UI (integration) tests as well as the normal unit tests. I wanted to get all of this integrated into my maven build, with code coverage reports so I could get an idea of areas with insufficient test coverage. Rather than just publish the source code for the project, I’ve ...

Hibernate (and actually JPA) has collection mappings: @OneToMany, @ManyToMany, @ElementCollection. All of these are by default lazy. This means the collections are specific implementations of the List or Set interface that hold a reference to the persistent session and the values are loaded from the database only if the collection is accessed. That saves unnecessary database queries if you only ...

Some time ago, I was the tech lead for a few very large deployments on the Real Estate market for companies like Fannie Mae, Freddie Mac, Foreclosure.com and HUD. We were running that traditional enterprise Java stack you are probably familiar with – Spring, Hibernate, Solr, etc. It took a few years but we had built a very nice system; ...