System settings rules define run-time settings that can differ based on a system's production level, and which are further resolved at run time through rule resolution. System settings are identified by name and owning ruleset. The owning ruleset functions as a namespace and does not have to equal the ruleset that contains the rule.
The benefit of defining a setting by production level means, for example, that if you create an application in a development area, and plan to move it to a test area and then into production, you can provide values for this System setting for each level, and then move the setting rule into each area without having to reset the rule value.
A predefined System setting can be overridden by saving it into a different ruleset, with the same name and owning ruleset name. At run time, rule resolution determines which version of the setting takes effect.
Custom settings can be created in one of your application's rulesets, and can be thought of as constant for that application, further defined by production level.
Circumstance and time-qualified resolution features are not available for System settings rules.
Your application can query instances of the System settings class using the Java get method in the PublicAPI PRSystemSettings interface. For more information, see Java methods for Dynamic System Settings and System settings.
These rule and data instances have similar names, but they are not related. For more information, see Contrasting System settings rules with Dynamic System Settings data instances.