The format of the resource strings for forms depends on if the form is associated with a container (application, directory, ...) or just a global form:

Container format

<object type>-<raw container name>-<variable>=Your localized text

No container format

<object type>-<variable>=Your localized text

Note that the name of the form is NOT in the format.  This allows you to specify the localized text once and anywhere that same variable is used the translation applies.

Example 1

If I had a variable named v1 on a global form for which I wanted to localize the form field question and tooltip, the process is to  specify in the customerstrings.properties or customerstrings_xx.properties for a specific language.  For example,
 

Global-v1=New Variable
Global-v1-tooltip=New Variable Tooltip!

Example 2

In this example, the form has a static text variable defined:

variable name: st_1
Text: Hello World.

You can optionally add a line to your customerstrings.properties file or just enter the default value in the form element text field:

Global-st_1=Hello World.

Then for other languages such as German add in a customerstrings_de.properties:

Global-st_1=Hallo Welt.

That would have the system display the German version when a user selected German as either their browser language and having that determine the UI language OR have German set as the UI language explicitly from the User Options Language tab (see the user icon in the upper right corner of  the UI).

If you need language localization in your form validation error messages, please review a thread on the RSA Link RSA Identity Governance & Lifecycle community on how to use customerstrings on form validation files that may help with your JSP.