Multiple installations on Windows

If you are running jEdit under Windows, follow these steps using jEditLauncher:

First, download the installer for the new version, save it to your desktop or some other temporary location, and run it by double-clicking its file icon (if you have associated .jar archive files with a Java application loader) or by running the loader - either java.exe or javaw.exe - from a command line with the -jar parameter and the full path of the installer file as the target.

Next, select an installation directory for the new version that differs from your existing installation directoy. The default value offered by the installer specifies the version in the directory's name, so that will work fine.

Next, make sure you uncheck the option for jEditLauncher in the next screen presented by the installer. It is the last option and is entitled "Windows launcher and context menu addition". You will actually continue to use your existing version of jEditLauncher in its current location. Select other options as you think fit, but remember that if you don't install macros, the new version won't be able to see the default macro set from your old jEdit installation.

Once the installation completes, open the jEditLauncher setup module, either by selecting "Set jEdit Parameters" in your Programs Menu for jEdit, or by running jedit /p from a command line that has your old jEdit installation directory in its search path.

You're almost done. If you run jEdit with the -jar option, change the "Location of jEdit executable" field to point to your new test version. If you do not use the -jar option and instead specifiy jedit.jar as part of your classpath parameter value, change that value to point to jedit.jar in the new installation's directory. Commit the new parameter values by clicking "OK" and you're ready to run the new version of jEdit with your existing settings, personal macros, startup scripts and plugin collection.

Multiple installations on other OS's

Linux users and others who run jEdit from a shell script can achieve the same result with a slightly different approach. Before running the installer for a new version, copy your existing jedit loading script to a new file indicating the application's version, like jedit322. After installing the new version in a new directory, rename the new jedit script and the old version to whatever names suit you.

Using plugins

One thing to remember when you try out jEdit 4.0 is that a number of plugins will not be compatible with the new version until they are updated to conform to a few changes in the application's API. For those plugins, you will get warning messages when you start up the new version of jEdit. You may also have exceptions thrown if a plugin loads successfully but contains code broken by changes in jEdit 4.0. If you want to avoid these messages, or if you want to test the new versions without any plugins, you can easily reorganize your plugins in a single-user installation.

Take all the plugins that you don't want in the test installation (along with source code, if you have downloaded it) and move them to the /jars subdirectory of your "stable" jEdit installation. They will not be loaded when you run a jEdit version located in another directory. All plugins you want for both versions should be in the /jars directory of your user settings directory, because both versions of jEdit will read that folder's contents on startup.