Tools

Migrate JUnit 4 to JUnit 5 using IntelliJ IDEA

IntelliJ IDEA provides a basic built-in support to migrate JUnit 4 to JUnit 5 tests. Even most of the steps to migrate JUnit 4 to JUnit 5 are already explained in the Jetbrains blog “Migrating from JUnit 4 to JUnit 5”, I would like to focus here on aspects that the current IDEA IntelliJ version, 2021.3.3 (Ultimate Edition) Build #IU-213.7172.25, build on March 15, 2022, does not cover. To enable the migration support you must enable the inspection in in Preferences | Editor | Inspections | JVM languages | JUnit 4 test can be JUnit 5. After you activated the inspection the migration is available at the class level and… Read More »Migrate JUnit 4 to JUnit 5 using IntelliJ IDEA

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 big files in the history and that let you select the files you want to remove with just a click of a button. Therefore I started the GitDirStat project on github and developed a java swing application based on the JGIT library provided by the eclipse community. The name was derived from the popular WinDirStat application or… Read More »GitDirStat – a git maintenance gui

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 in a git repository like creating a commit or updating the refs during a push command. I developed a small bash script that can be used to execute checkstyle on every push and that rejects changes that have checkstyle errors. The script is simple and easy to configure so I want to share it here. Just… Read More »A git checkstyle pre-receive hook

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.

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 an SSL socket a ClassNotFoundException: com.ibm.websphere.ssl.protocol.SSLSocketFactory is thrown. This exception is often the root cause of other exceptions. Caused by: java.net.SocketException: java.lang.ClassNotFoundException: com.ibm.websphere.ssl.protocol.SSLSocketFactory at javax.net.ssl.DefaultSSLSocketFactory.throwException(SSLSocketFactory.java:198) at javax.net.ssl.DefaultSSLSocketFactory.createSocket(SSLSocketFactory.java:205) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.apache.commons.httpclient.protocol.ReflectionSocketFactory.createSocket(ReflectionSocketFactory.java:116) at org.apache.commons.httpclient.protocol.SSLProtocolSocketFactory.createSocket(SSLProtocolSocketFactory.java:130) at org.apache.commons.httpclient.HttpConnection.open(HttpConnection.java:707) at org.apache.commons.httpclient.MultiThreadedHttpConnectionManager$HttpConnectionAdapter.open(MultiThreadedHttpConnectionManager.java:1361) at org.apache.commons.httpclient.HttpMethodDirector.executeWithRetry(HttpMethodDirector.java:387) at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:171) at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:397) at com.sun.jersey.client.apache.DefaultApacheHttpMethodExecutor.executeMethod(DefaultApacheHttpMethodExecutor.java:210) … 18 more… Read More »How to fix java.lang.ClassNotFoundException: com.ibm.websphere.ssl.protocol.SSLSocketFactory in eclipse

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 is a short answer and is intended for those of you who only want to quickly remove files and don’t want to undestand it in-depth. The section chapter dives into the depth of git and gives you links to other resources to understand how files are managed in git and thus can be removed. The short answer… Read More »Remove directories and files permanently from git

Separation of api and implementation

In every project you have to deal with apis and their implementations. While a lot of projects separate the api from it’s implementation through different java packages (mostly named internal or impl), I want to show you another approach and tell you why this approach makes more sense. I call this other approach “implementation separation by packaging artifact”. Let’s take a look at a widly used project structure that separates the api from the implementation by using a separate impl package. This kind of separation is widely used but it has a some impacts on design and api usage as I will show now. Api and implementation dependencies differ The… Read More »Separation of api and implementation