Java-MySQL Program

It turns out that configuring Perl wasn’t the last step for my student instance. It appears that I neglected to configure my student instance to support Java connectivity to MySQL. This post reviews the configuration of Java to run programs against MySQL. It also covers the new syntax on how you register a DriverManager, and avoid Java compilation errors with the older syntax.

In prior posts, I’ve shown how to use Perl , PHP (more...)

Donderdag 16 april/Thursday April 16th – Speedy Joe’s – Using asynchronous interaction in Java EE to turn the world’s slowest restaurant into a super performant place

De Java SIG (Special Interest Group) van AMIS organiseert op donderdag 16 april een bijeenkomst (publiek toegankelijk) over asynchrone interacties in Java EE (web) applicaties. Synchrone interacties in de echte wereld en in IT applicaties kunnen de boel behoorlijk ophouden. Synchroon betekent wachten – en resources vasthouden. Dat kan een probleem vormen voor schaalbaarheid en performance. In deze sessie leer je dit probleem te tackelen.

imageDeze SIG is interessant voor ontwikkelaars met JAVA kennis en (more...)

Java EE 7 Hands-on Lab – free

clip_image002This page provide instructions and starting code for the Java EE 7 hands-on lab. The hands-on lab builds a typical 3-tier end-to-end application using the following Java EE 7 technologies:

Specification Name

JSR #

Java API for WebSocket 1.0

JSR 356

Batch Applications for the Java Platform 1.0

JSR 352

Java API for JSON Processing 1.0

JSR 353

Java Message Service 2.0

JSR 343

Java API for RESTful Web Services 2. (more...)

Java and IoT: The Intelligent Platform for the Connected Vehicle Whitepaper

clip_image002A vehicle is typically the most expensive and complex consumer device that we own. We expect it to keep up with the rest of our devices that produce and consume a rapidly growing set of media and social data. We also expect vehicles to be 100 percent reliable and to keep us safe. Meeting all of these needs is a challenge for manufacturers that have a growing set of requirements themselves. For instance, manufacturers need (more...)

Exposing JMS queues and topics with a JAX-WS webservice

Everyone can do HTTP calls and thus call most webservices. Interfacing with JMS queues or topics though is a bit more difficult (when not using Oracle SOA Suite). An alternative is using custom code. This usually requires libraries, JNDI lookups, opening connections and such. Because I wanted to make it easy for myself to put stuff on queues and topics, I created a simple JAX-WS wrapper service. By using this service, JMS suddenly becomes a (more...)

Access Denied when logging in to OSB 12c console

The Oracle SOA Suite 12c quick start is an excellent way to get started with all the new features of 12c. I imagine it must be frustrating when you log in to http://localhost:7101/servicebus and are confronted with an 401 – Access Denied error message. Rest assured, there is nothing wrong with your credential configuration. The cause is likely much more simple; you use the wrong Java version.

Although the certification matrix for FMW 12.1. (more...)

Quick and dirty test for thread leakage in java

I was looking at a bit of code was leaking class loaders when deployed to tomcat - so I wanted to quick rule out that a background Thread was holding onto the loader. Pain by eye, it is quite easy with a few unix commands to process the stack trace, filter for the lines that contain the thread name, filter for just the thread names and sort:
sudo -u tomcat jstack 1853 | grep "  (more...)

A JavaFX 8 Stock Ticker application

Since Java SE 7, update 6 , JavaFX is part of the Java SE, it is officially replacing Swing as Oracle’s UI library for Java, and it runs on (any) desktop, mobile, and within the browser (applet). Java SE 7 includes version JavaFX 2.2, Java SE 8 includes JavaFX8, the version we will use here.

In this blog, I would like to demonstrate how to create a simple stock ticker, written in JavaFX. Data will be fetched (more...)

So you’ve dumped 150 GiB of JVM heap, now what?

150 GiB worth of JVM heap dump is laying on hard drive and I need analyze specific problem detected in that process.

This is a dump of proprietary hybrid of in-memory RDBMS and CEP system, I'm responsible for. All data are stored in Java heap, so heap size of some installation is huge (400 GiB heap is largest to the date).

Problem of analyzing huge heap dumps were on my radar for some time, so (more...)

Découverte : Java Cloud Service Workshop


Marcus Lagergren 20 years of Java In Review

We know each other since some years now. And I am very very pleased to see, that we finally could make it happen to have him speaking at JavaLand as a Keynoter. And what would be better for a JVM veteran than talking about this years anniversary: Happy Birthday Java!
Thank you Marcus, for taking the time!

I am looking forward to a beer or two at JavaLand! Follow his rumblings about dynamic languages on (more...)

Binary search – is it still most optimal?

If you have a sorted collection of elements, how would you find index of specific value?
"Binary search" is likely to be your answer.
Algorithms theory is teaching us what binary search is most optimal algorithm for this task with log(N) complexity.
Well, hash table can do better, if you need to find key by exact match. In many cases, though, you have reasons to have your collection sorted, not hashed.

On my job, I'm (more...)

Moving My Beers From Couchbase to MongoDB

See it on my new blog : here Few days ago I have posted a joke on Twitter Moving my Java from Couchbase to MongoDB pic.twitter.com/Wnn3pXfMGi — Tugdual Grall (@tgrall) January 26, 2015 So I decided to move it from a simple picture to a real project. Let’s look at the two phases of this so called project: Moving the data from Couchbase to MongoDB Updating the application code to use

JDeveloper Debugging Tips (Watchpoints & Beep)

In a previous blog post I talked about scoping breakpoints for debugging purposes, next to scoping breakpoints JDeveloper has more interesting debugging features to offer.

I created a simple example to show both the watchpoint as well as the beep functionality. To illustrate this, I created a page with an inputText and a button, both bound to a backingBean. 

This  is the jsf code:
 



The code from the bean is also pretty straight forward:
    (more...)

But that’s impossible, or finding out that the JIT has broken your code.

Every now and then you look at some code and think that it cannot be possibly be wrong. Once you have ruled out a simple programmer screw up / enemy action in code (Make sure you read Java Puzzlers or similar) or a concurrency issue (Read Java Concurrency or go on Dr Heniz excellent course) you should sit back and take a few days and then starting thinking about whether the JDK is indeed (more...)

Exciting things happening in Coherence…

I hope everyone is attending/watching JavaOne 2014 tomorrow.   There’s a sneak preview of some cool next generation Coherence with Java 8 in the Java One Technical Keynote

Follow @JavaOneConf and @pinocchiocode to find out more…


Oracle SOA Suite 12c tips – Tuning the SOA infrastructure thread pool

One of the new capabilities of Oracle SOA Suite 12c is the ability to control the SOA infrastructure thread pools, except the resource pools for EDN and the adapters, with Oracle WebLogic Server work managers. Each partition will has its own work managers defined. This allows you to separate services in partitions and, to some extent, tune them separately based on for example specific SLA requirements.

Well, this blog posting is not about explaining the (more...)

Open Source as religion – when the Bazaar becomes a Cathedral

The seminal book on Open Source development "Cathedral and the Bazaar" talks eloquently about the difference between commercial software development and open source development.  In the past few years however there has been another shift, a shift where companies are actively releasing their technology into Open Source as a competitive differentiation.  A claim of 'we are open' because the source

Share your source between projects

Normally we pack functionality into libraries and use this library to share the functionality. However, during development of several JDeveloper Extensions our goal was to have one shared java source between our JDeveloper 11g and JDeveloper 12c extension.
Off course we wanted the ability to easily develop, test, debug and run the extension, but we also want to share the java code to introduce reusability.

We accomplished this, by creating a separated ‘coresrc’ folder and (more...)

Java Cookbook 3rd Edition

Java is a programming language and computing platform. There are lots of applications and websites have used it. About latest Java version, Java 8. Oracle announced Java 8 on March 25, 2014. I mention a book title - Java CookbookJava Cookbook by  Ian F. Darwin and this book covers Java 8.
 It isn't a book for someone who is new (Readers should know a bit about syntax to write Java) in Java, but It is (more...)