Preferences 2 Go

Changes an existing application from using standard Java Preferences to using an implementation of Java Preferences that lives in memory only and loads the preference values from a file on startup.

This is specifically useful if you do not have access to the source code of the original application and if you are seeing too many problems with using a Preferences implementation that uses Windows Registry or hidden files on Linux/Solaris. For example you may be encountering BackingStoreException(s) and you really just want the configuration values for your application to reside within a configuration file next to your application without involving things like Windows Registry or obscure hidden files. This is what Preferences2Go gives you..... all without changing the underlying application.

Configuration

Download the pref2go.jar from the releases section of GitHub.

Now make sure that pref2go.jar is on your classpath.

On startup of your application you'll then need to set one or more of the system properties below:

System Property	Description
java.util.prefs.PreferencesFactory	Mandatory. Must be set to com.addicticks.preferences2go.TemporaryPreferencesFactory
pref2go.xmlFile	Optional. If set it's assumed to be the name of a Java Preferences XML file conforming to the DTD as explained in the Javadoc for Preferences. The content of this XML file will be loaded on startup. The file will only ever be read, never written to.
pref2go.printPref	Optional. If set to "true" the contents of the loaded preferences are pretty printed and logged to standard logger (level INFO) on startup. This only has effect if property pref2go.xmlFile is also set.

That's all. Your application now no longer attempts to use a Preferences implementation that uses Windows Registry. The change is completely transparent to your existing application.

Example

Let's assume myapp is started as follows:

#!/bin/bash
CP="myapp.jar"
SYSPROP=""

java -classpath $CP $SYSPROP myapp.StartUp

then simply change like this:

#!/bin/bash
CP="myapp.jar:pref2go.jar"
SYSPROP="-Djava.util.prefs.PreferencesFactory=com.addicticks.preferences2go.TemporaryPreferencesFactory -Dpref2go.xmlFile=../config/myConfig.xml -Dpref2go.printPref=true"

java -classpath $CP $SYSPROP myapp.StartUp

Thomson Reuters RFA Java users

For users of the Thomson Reuters RFA Java API there's a simple way to generate the config file if you already have your preference values stored in the classic Preferences backing store.

From the SDK's Tools folder execute either config_editor.bat (if on Windows) or config_editor.ksh (if on Linux/Solaris).

From within the Configuration Editor export the values as follows:

The file that was created as a result of this can then be used as pref2go.xmlFile.

Restrictions

Unlike standard Preferences any changes made to the preferences by the application will not be persisted. In other words: there's no attempt to to write to file pointed to by pref2go.xmlFile or anywhere else.