Liferay Standard Development Environment

I wrote a post a while back outlining the general set up we use when running our Liferay plugins through Continuous Integration, but it occurred to me that there should be an article that comes before that one which outlines the set up of the development environment. Many of the results of the decisions and best practices can be seen in that post, but there is still plenty that can be covered with respect to setting up a development environment for Liferay plugins.

Development Environments

There a few slight changes to the setup described in the previous article, but we’ll assume that a Liferay project always requires the following tools:

  • Liferay Development Studio (LDS). This is essentialy the Eclipse IDE plus some Eclipse plug ins to assist Liferay development.
  • Liferay Software Development Kit (SDK). This does most of the work with respect to building the plugins and the ANT tasks can be used from the command line without requiring the LDS.
  • A Liferay Bundle. A bundle is a pre-packaged Liferay server instance and in our case we tend to use Liferay bundled with Tomcat almost exclusively during development. The other benefit is that the Tomcat bundle is already assumed and pre-configured for some of the steps below and hence simplifies set up and reduces the work and chances of getting things wrong later.
  • Liferay Source. This isn’t essential to the set up, but when creating a new development environment we always do this at the same time and there or little additional effort required.


Install Liferay Development Studio

You can install the LDS to the location of your choice and you can use the same LDS instance to manage multiple Liferay project workspaces, but more on this as we go. If you have already installed LDS then there is no need to do it again.

Create a new workspace directory for the Liferay project. For the sake of this article we’ll call the directory workspace.

Note that the Liferay source, SDK and bundle in the next steps should all be for the same version. Don’t mix them up. You have been warned.

Install Liferay Software Development Kit (SDK)

Copy the Liferay SDK zip file eg to the workspace. Unzip the file so that there is a directory with the same name eg liferay-plugins-sdk-6.0-ee-sp1.

If your operating system does not allow soft links to directories, rename the SDK directory to plugins. Otherwise (and preferably) create a soft link to the SDK directory called plugins. By pointing external configuration at the plugins directory rather than at a specific SDK version, it makes it easier to upgrade your development environmnet later on.

Hopefully it gives you something like this in the workspace directory.

drwxr-xr-x 13      4096 2011-05-26 12:00 liferay-plugins-sdk-6.0-ee-sp1/
-rw-r--r--  1   9358463 2011-03-09 23:38
lrwxrwxrwx  1        71 2011-05-26 08:17 plugins -> liferay-plugins-sdk-6.0-ee-sp1/

Install the Bundle

Very similar to the previous step, copy the bundle zip file to the workspace, unzip and either rename or soft link as bundles. The bundles name is important here, so don’t get creative.

This adds the following to our directory:

lrwxrwxrwx  1        66 2011-05-26 08:18 bundles -> liferay-portal-6.0-ee-sp1/
drwxr-xr-x  5      4096 2011-05-26 16:32 liferay-portal-6.0-ee-sp1/
-rw-r--r--  1 187336800 2011-03-09 23:37

Install the Source

Once again copy the source zip file to the workspace directory, unzip and rename or soft link as source.

drwxr-xr-x 20      4096 2011-05-26 09:47 liferay-portal-src-6.0-ee-sp1/
-rw-r--r--  1 230320369 2011-03-09 23:37
lrwxrwxrwx  1        70 2011-05-26 08:18 source -> liferay-portal-src-6.0-ee-sp1/

The complete Workspace

Remove the zip files if you want, but personally I just leave them there. The parts we’re interested in are the bundles, plugins and source directories.

lrwxrwxrwx  1        66 2011-05-26 08:18 bundles -> liferay-portal-6.0-ee-sp1/
drwxr-xr-x 13      4096 2011-05-26 12:00 liferay-plugins-sdk-6.0-ee-sp1/
-rw-r--r--  1   9358463 2011-03-09 23:38
drwxr-xr-x  5      4096 2011-05-26 16:32 liferay-portal-6.0-ee-sp1/
drwxr-xr-x 20      4096 2011-05-26 09:47 liferay-portal-src-6.0-ee-sp1/
-rw-r--r--  1 230320369 2011-03-09 23:37
-rw-r--r--  1 187336800 2011-03-09 23:37
lrwxrwxrwx  1        71 2011-05-26 08:17 plugins -> liferay-plugins-sdk-6.0-ee-sp1/
lrwxrwxrwx  1        70 2011-05-26 08:18 source -> liferay-portal-src-6.0-ee-sp1/

How the parts interact

Before we complete the configuration, we’ll pause and look at how the parts interact.

Liferay Development Studio (LDS) and Software Development Kit (SDK)

The LDS provides some wizards, configuration checking and general assistance in building and managing Liferay plugins, but mostly it delegates to the SDK to perform the actual build and deploy work.

Therefore in just a second we’ll tell the LDS where the SDK is but first a word of warning…

Excuse me for shouting, but only ever register a single SDK with a Liferay workspace, and make sure it is the one in the workspace called plugins. Having multiple SDKs registered with in a single workspace can cause confusion or worse, and doesn’t add benefit to the environment. Please don’t do it.

LDS and the Bundle

LDS is able to start/stop the bundle but is also able to shortcut the deployment process and deploy straight to the bundle without needing help from the SDK.

Depending on the LDS version used, you may be asked to point to a bundle (or Liferay Runtime) the first time you point the LDS to a new workspace. Be sure to point to the workspace/bundles directory.

SDK and the Bundle

The SDK uses the libraries in the bundle to compile the plugins, and it also needs to know the location of the bunlde directory so that the deploy target can copy the WAR files to the Liferay Runtime


As pointed out above, you should only configure a single SDK in the LDS for a given workspace. When you point the LDS to another workspace you are able to specify a different SDK as this value is configured against the workspace and is not global to the LDS. This will come as a major relief as the alternative would be incredibly restricting.

Furthermore, the plugins also have the registered name of the SDK included in their project properties, so it is important that all team members use the same name to describe the SDK within the LDS. I believe our default is liferay_sdk but it doesn’t matter what is selected provided everyone uses the same value. If not, you’ll be forced to fix this value every time someone else changes it in version control, and you’ll be unable to build or deploy until it is corrected. It is very annoying.

We may have already specified the Liferay Runtime when first pointing the LDS at the new workspace, but if not go to the LDS menu and select Window > Preferences and on the Preferences screen select Server > Runtime Environments, select ‘Add’, select the Liferay version for your bundle from the servers available and then point to the workspace/bundles/tomcat directory.

The next step would be to configure the SDK and bundle to work together, but as hinted earlier we don’t need to. If you look into the workspace/plugins/ default settings, the server is already set to tomcat and the server location and deploy folder location are already correct because we have a directory called bundles pointing to the Runtime home directory.

Finally, right click on some spare space in the Package Explorer in the LDS, import, general, import and existing Eclipse project, navigate to the workspace directory, click OK and then select the source directory to import. This is useful for development and debugging.

Creating a new Plugin

When you create a new plugin project in the LDS, the wizard wants to know which SDK to use and since we have a single SDK there is no problem. The wizard ends up creating a new project in one of the subdirectories under the plugins directory, but within the LDS the project will display as if it were in the root directory of the workspace. It isn’t, but it is worth knowing the difference. If you get confused, right click the project in the LDS, go to the properties and look at the resource location.

Plugin Version Control

It is a bad idea to check the entire SDK into version control, so it is lucky that the LDS places them at the base of the Project Explorer. Right click, team, share, happiness.

Adding a Liferay plugin project from version control back into the LDS has some tricks to it.

Firstly, you’ll want to place the plugin project in the correct subdirectory in the SDK. When you import the project from version control, the second screen in the import wizard prompts you to import into the default workspace location. Don’t do this, and instead select the correct SDK subdirectory for that Liferay Plugin project type. But that’s not all.

Unless the bug has been fixed since the last time I checked, importing from version control will get the project into your LDS workspace, but the plugin will be imported as a Java project and not a Liferay Plugin Project; some of the Eclipse facets are lost. This matters. To fix it, right click and delete the project(s) that you just imported from version control but do not delete from the file system. Once again right click on some free space in the LDS Package Explorer, import, LIferay > Liferay Plugin SDK Projects, select the one and only SDK, select the project(s) to import and then they get imported correctly as Liferay Plugin projects.


So while I haven’t spelled out all of the learnings and reasons which has led us to this set up as our preferred Liferay Standard Development Environment, I hope that there are enough reasons provided for you to consider this approach and I hope that there are sufficient instructions provide to recreate the same in your own workspace.

Installing the Adobe AIR 2 SDK in Eclipse

While Adobe makes adding a new Flex SDK easy – just drop a new version folder alongside another version and point Eclipse to the new directory – they make installing a new Air SDK quite frustrating. The Air SDK is installed inside the Flex SDK, so to truly install a new version, you must hijack your existing Flex SDK and replace a few dozen files within the folder structure. It is my sincere hope that Adobe moves away from this coupling and allows Air SDKs to be more easily upgraded in the future without the need to piecemeal copy them onto an existing Flex SDK installation.

Below is short story of how I managed to get my application to build Adobe Air 2.0 applications with Eclipse and the steps I took to resolve the numerous issues that cropped up.

1. Download and Install the Air 2 Runtime and Air 2 SDK

The first step is to download the Air 2 runtime which installs itself within the operating system. The second step is to download the Air 2 SDK, which downloads as a zip file. Assuming you have Flex 2, 3, or 4 installed, there should be a plugin sdks directory that contains an AIR runtime folder such as:

Flex SDK root: C:\Program Files (x86)\Adobe\Flex Builder 3 Plug-in\sdks\3.2.0
Air Runtime root: C:\Program Files (x86)\Adobe\Flex Builder 3 Plug-in\sdks\3.2.0\runtimes

Backup (for safety) the runtimes folder and replace it with the one in the Air 2 SDK zip file. Congratulations, you have just installed the Air 2 SDK!

Note: You may have multiple Flex SDK folders on your computer with multiple versions. You should use whichever one your version of Eclipse is pointing to, or create a new version (“3.2.0-air2” for example), and point Eclipse to this new version.

2. Turning on Air 2 within your application

Next, try building and running your Air project within Eclipse using the Flash Builder plugin. Upon launching the compiled application, you will likely see the message “IIMEClient error”:

IIME Client Error

A little bit of digging, shows the error is caused by a combination of the following:

Flash Builder 4 + AIR 2.0 SDK + Application with AIR 1.5 app-descriptor

In short, the app-descriptor for my application (such myApplication.xml) requires that the namespace reference xmlns be changed from

Once you change the version number, the application will compile and run without issue.

3. Full installation of Air 2 SDK required for Release Builds

While you can now build and run Air 2 applications within Eclipse, you will receive an error if you try to Export them as Release Builds. To resolve this issue you go back to step 1 and this time merge all of the files from your Air 2 SDK zip file onto your Flex SDK directory. This is especially risky, since you are replacing dozens of files throughout the SDK, so this time make sure to backup your entire Flex SDK folder. You should expand the zip file and replace over all files and folders.

For example, in the sub-directory bin replace two files from the Flex SDK: adl.exe and adt.bat, but leave the existing files in that folder in place. The rest of the files contained in the zip file should be used to replace the existing SDK files in a similar manner. Many operating systems offer a merge functionality that will only replace the files that have changed and keep the existing files in place.

After you are done, you can open a command window, navigate to the SDK bin folder and type “adt -version” to determine which version of Air is installed. My thanks to Michael Christoff for this part of solution that works on any OS.

The Result

Now you should be able to build, run, and release an Adobe Air 2 application. You can test this by exporting your Air Application to a .air release file, then installing your application using the Air 2 graphical runtime which was installed at the beginning of this process.