René Link

René Link

About René Link

I'm a software developer since 2002 and founded my company Link Intersystems in 2011. My favorite programming language is Java, but I m also experienced in other languages. I focus on design and architecture of java enterprise applications with spring, hibernate or jee. Software quality and therefore clean code belong to my basic principles. ---- If you want others to take you seriously, than take your craftsmanship seriously - be a professional ---- Visit me on careers 2.0 and follow me on stackoverflow.com

Bugs love logging to hide

A lot of projects run integration and unit tests, but often miss a little something – logging. When you use logging you often check if the log level is enabled or not before you log. But this means that you introduce a control flow statement that enables or disables some code. So if you […]

GitDirStat – a git maintenance gui

Some time ago I wrote the blog “Remove directories and files permanently from git”. Removing files from a git history is not an unusual task and I thought that it would be nice if there is an easier and faster way to do it. I thought that there should be a gui that help you to find […]

By |December 28th, 2014|Git|0 Comments

A git checkstyle pre-receive hook

When multiple developers work on one project it is also essential that they all commit source code that matches some formatting rules. Otherwise reviewing changes and merging source code can be a great challenge.

When using git repositories you can install hooks. Hooks are any kind of executables that can be run before something happens […]

By |December 7th, 2014|Git|1 Comment

How to create an independent branch in git

In a git repository everything normally starts with an initial commit and all other commits are ancestors of this first commit. But is it possible to create a second initial commit or even a third? Another initial commit with a complete different working directory? Yes it is.
By |November 23rd, 2014|Git|0 Comments

Clean Code with underscores in literals

As of java 1.7 the java language specification allows integer literals to contain underscores in order to make them more readable. If it is applied in a good way it can enormously increase the readability of your code.

In java 1.6 one had to define integer literals like this:

With java 1.7 such integer literals can be […]

Custom swing component renderers

This blog shows how to implement a custom swing component renderer using the example of a ListCellRenderer.
By |October 19th, 2014|JDK, Swing|1 Comment

How to fix java.lang.ClassNotFoundException: com.ibm.websphere.ssl.protocol.SSLSocketFactory in eclipse

If you use IBM’s WebSphere plugin for eclipse you might have the problem that other plugins can’t establish an SSL connection anymore. The result is most times a ClassNotFoundException: com.ibm.websphere.ssl.protocol.SSLSocketFactory. This blog explains the reason behind the problem and gives a workaround to prevent that exception.
Problem description
When a component within eclipse (e.g. atlassian jira connector) tries to connect to […]

Remove directories and files permanently from git

Some day you might want to remove files or directories from git permanently, because someone committed sensitive data or large binary files that should not reside in the repository to keep clone times short.  In this blog I want to show you how to delete directories and files permanently from a git repository.

The first chapter […]

By |July 17th, 2014|Git|4 Comments

How to fix IBM Websphere ant task error: Unable to parse setupCmdLine: null\bin\setupCmdLine.bat

When trying to execute a wsadmin command using ant you might get the error
Unable to parse setupCmdLine: null\bin\setupCmdLine.bat  (The system cannot find the path specified)
This error is caused when you don’t provide the user.install.root system property or no wsadmin task profileName property.

In order to fix you can either add a user.install.root property and point it to your websphere profile directory (in default installations […]

How to fix IBM Websphere JNDI exception “cannot find the factory for this scheme: java”

Some time ago I stumbled on a weird exception when deploying an EAR on IBM WebSphere Application Server 8.5. The EAR got successfully installed, but when the application server tried to start the WAR archive of my EAR I got this exception:

After searching the web for this exception I came to the conclusion that I have to […]