Posts Tagged ‘ide’

IntelliJ IDEAs new directory-based project format

Posted in java, software development, tools on October 17th, 2009 by Joerg – 9 Comments

I am currently playing with the EAP-Version (Early Access Program) of my favorite IDE IntelliJ IDEA. Since the new version is not that far away it is time to learn the new features and I discovered one that surprised me. A small but pretty nice change.

(Update: Thanks to Strug I have realized that this feature is already present in Idea 8, you can use the action “Open in New (Directory based) format” to convert your project. Fortunately they renamed it to “Save as Directory-Based Format …” in Maia. )

IDEA has a new format to store the project files. It is called directory-based. Instead of using the three famous files .ipr .iml and .iws IDEA will now store all information into a directory, which is simply called .idea. It is located in the root folder of the project. This seems to be somewhat similar to eclipse’s .project folder. In a small example project I created the content of the new directory looks like this:

-rw-r--r--  1 joerg  joerg    163 17 Okt 09:53 ant.xml
-rw-r--r--  1 joerg  joerg   2107 17 Okt 09:53 compiler.xml
drwxr-xr-x  3 joerg  joerg    102 17 Okt 09:53 copyright
drwxr-xr-x  3 joerg  joerg    102 17 Okt 09:53 dictionaries
-rw-r--r--  1 joerg  joerg    277 17 Okt 09:53 encodings.xml
-rw-r--r--  1 joerg  joerg    170 17 Okt 09:53 fileColors.xml
-rw-r--r--  1 joerg  joerg   1595 17 Okt 09:53 misc.xml
-rw-r--r--  1 joerg  joerg    258 17 Okt 09:53 modules.xml
-rw-r--r--  1 joerg  joerg    207 17 Okt 09:53 templateLanguages.xml
-rw-r--r--  1 joerg  joerg    169 17 Okt 09:53 vcs.xml
-rw-r--r--  1 joerg  joerg  38245 17 Okt 10:21 workspace.xml

The files included in this directory depend on the settings you change in the IDE. So, if you would for instance set the SQL dialect for your project there will be another file called sqldialects.xml containing all settings about this.

There is one special file in there, which is workspace.xml. This file contains individual settings for the workspace, which are definitely not intended to be shared via version control. This is equivalent to the .iws file of the old format. IDEA will put this file automatically on the ignore list of your version control.

I see some advantages of the new format.

  • First of all it is easier to find specific settings. The filenames are meaningful and the files are small.
  • The new structure allows a very detailed control of which settings you want to share with your colleagues. If you don’t want to share e.g. your file coloring (another new feature of Maia) just put the file on the ignore list.
  • Directories of the projects saved in the new format will be recognized as projects in the open-project dialog. In the past this was one annoying additional click as you had to choose the .ipr file before.

The new directory based format is a small change but a very good one. It is often a sum of little detail-improvements that save a lot of trouble in daily work. So I am looking forward to the other details to be discovered.

By the way JetBrains released an open source version of IDEA two days ago. So if you want to try this just go to and download the Community Edition.