Parent category
In order to test a particular feature of our JEE application I installed a free copy of MS SQL Server 2012 Express. I’m a total MS SQL illiterate. As always with MS SQL I used the jTDS JDBC driver to connect from Java. The first hurdle was to learn that MS SQL Express by default […]
final Image image = …; final ByteArrayOutputStream baos = new ByteArrayOutputStream(); try { final BufferedImage bufferedImage = createBufferedImageFrom(image); ImageIO.write(bufferedImage, “png”, baos); } finally { IOUtils.closeQuietly(baos); } return baos.toByteArray(); private BufferedImage createBufferedImageFrom(final Image image) { if (image instanceof BufferedImage) { return (BufferedImage) image; } else { final BufferedImage bi = new BufferedImage(image.getWidth(null), image.getHeight(null), BufferedImage.TYPE_INT_RGB); final Graphics2D […]
If your application sends SMS you want to make sure that characters to be sent comply with GSM 03.38 (e.g. 7bit). If you need to validate (user) input for invalid characters you could do that pretty easily with regular expressions. For Java the following regex is ready to use. For other languages you can base […]
dnsjava to resolve whatever address request.getRemoteAddr() would return. This worked very well in most cases. However, in some cases I would see something like: [quote]java.net.UnknownHostException: Invalid address: fe80::1d9:b65a:ed86:7940%11[/quote] Not being much of a networking expert I was puzzled about the ‘%11’. Once again superuser.com came to rescue: http://superuser.com/questions/99746/why-is-there-a-in-the-ipv6-address
At the technical panel discucssion on Friday morning at Devoxx there was the interesting question “Does Oracle’s corporate culture stand in the way of success for Java?”. Even more interesting was the answer from either Brian Goetz or Mark Reinold (don’t remember), both big wigs at Oracle… “I think Java became a success despite Sun’s […]
The two keynotes at Devoxx 2011 yesterday by Henrik Ståhl and Cameron Purdy from Oracle and today by Google’s Tim Bray couldn’t have been more different. If that is all Oracle’s got to bring to the table then I fear they’re in big trouble… While Henrik Ståhl showed at least some passion and inspiration (neatly […]
he = Uncle Bob it = writing a book about Clean Code I started reading “The Clean Coder” the same day it arrived at my desk. Contrary to “Clean Code”, Uncle Bob’s previous book, it was supposed to about coding /practices/ rather than code. As such it should be about the the behavior of engineers […]
With a newly set up Maven project I tried deploying the site using mvn site:deploy. The command kept failing with the following error Embedded error: Error performing commands for file transfer Exit code: 0 – bash: unzip: command not found for the longest time. I tried all kinds of funny things although I was 100% […]
…not really learning DOT because it’s so simple – at least in its most basic form. I don’t understand why it took me so long to finally sit down and understand how the input for Graphviz works. What a glorious day today… You want to learn DOT, too? Wonderful, for a quick-start try this online […]
Creating a DDL in the Maven build with the hibernate3-maven-plugin fails if you explicitly configure an array of javax.persistence.CascadeType values in your JPA annotations. The stacktrace is similar to javax.persistence.PersistenceException: [PersistenceUnit: spontacts] Unable to configure EntityManagerFactory at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:265) at org.codehaus.mojo.hibernate3.configuration.JPAComponentConfiguration.createConfiguration(JPAComponentConfiguration.java:28) … Caused by: java.lang.ArrayStoreException: sun.reflect.annotation.EnumConstantNotPresentExceptionProxy at sun.reflect.annotation.AnnotationParser.parseEnumArray(AnnotationParser.java:673) at sun.reflect.annotation.AnnotationParser.parseArray(AnnotationParser.java:462) Once I realized what the actual […]