Commit a8c9329

- [Getting global variables](#getting-global-variables)

- [Getting aggregate evaluations](#getting-aggregate-evaluations)

- [Sticky features and variables](#sticky-features-and-variables)

- [`sticky_features_set`](#sticky_features_set)

- [`sticky_variables_set`](#sticky_variables_set)

<version>4.0.0</version>

Concurrent evaluations are safe after an instance is configured. Do not call state changing methods such as `setDatafile`, `setContext`, `setStickyFeatures`, `setStickyVariables`, `addModule`, `removeModule`, or `close` concurrently with evaluations or with each other. Apply those changes from a serialized update path. Module, event, and diagnostic callbacks must synchronize mutable state that they capture.

We can evaluate flags, variations, variables inside features, and [global variables](https://featurevisor.com/docs/global-variables/):

- [**Global variables**](#getting-global-variables): reusable values that are not owned by a feature

Global variables use the same overloaded methods as variables inside features. A call with one key evaluates a global variable, while a call with a feature key and variable key evaluates a variable owned by that feature:

String message = f.getVariableString("welcomeMessage", context, null);

Object value = f.getVariable("checkoutSettings", context);

Evaluation evaluation = f.evaluateVariable("checkoutSettings", context);

The type specific methods are `getVariableBoolean`, `getVariableString`, `getVariableInteger`, `getVariableDouble`, `getVariableArray`, `getVariableObject`, and `getVariableJSON`.

Global variables resolve sticky values first, then required features, then the first matching override, and finally their default value. If required features are unmet, `disabledValue` is used unless `useDefaultWhenDisabled` is enabled. Caller defaults are only used when the evaluation itself has no value.

EvaluatedFeatures allEvaluations = f.getFeatureEvaluations(context);

Map<String, Object> variables = f.getVariableEvaluations(context, null, null);

For the lifecycle of the SDK instance in your application, you can set some features with sticky values, meaning that they will not be evaluated against the fetched [datafile](https://featurevisor.com/docs/building-datafiles/):

Sticky values belong to an SDK or child instance. Feature sticky values and global variable sticky values are independent.

.stickyFeatures(stickyFeatures)

.stickyVariables(Map.of("welcomeMessage", "Hello")));

f.setStickyFeatures(stickyFeatures, true); // replace existing sticky features

f.setStickyVariables(Map.of("welcomeMessage", "Welcome back"), true);

By default, `setDatafile(datafile)` merges the incoming datafile with the SDK's stored datafile. Incoming top level metadata is used, and incoming segments, features, and global variables override existing entities with the same keys.

@SuppressWarnings("unchecked")

List<String> variables = (List<String>) event.get("variables");

The `features` and `variables` arrays contain directly changed entities and entities affected through segment or required feature dependencies.

FeaturevisorUnsubscribe unsubscribe = f.on(FeaturevisorEventName.STICKY_FEATURES_SET, (event) -> {

FeaturevisorUnsubscribe unsubscribe = f.on(FeaturevisorEventName.STICKY_VARIABLES_SET, (event) -> {

@SuppressWarnings("unchecked")

List<String> variables = (List<String>) event.get("variables");

});

Evaluation evaluation = f.evaluateVariable(variableKey, context);

For feature evaluations, all `before` callbacks run in registration order, followed by all `beforeEvaluation` callbacks. After evaluation and caller defaults, all `afterEvaluation` callbacks run, followed by all `after` callbacks. Global variable evaluations use only `beforeEvaluation` and `afterEvaluation`. Required feature checks run through the complete module pipeline, and transformed defaults are preserved.

// before any feature or global variable evaluation

.beforeEvaluation(options -> options)

// after any feature or global variable evaluation

.afterEvaluation((evaluation, options) -> evaluation)

- `setStickyFeatures`

- `setStickyVariables`

- `getFeatureEvaluations`

- `getVariableEvaluations`

<version>4.0.0</version>

Use `checkout` for a flag, `checkout:variation` for its variation, `checkout:title` for its `title` variable, and `variable:welcomeMessage` for a global variable. Boolean variables use the boolean resolver. Lists, structures, and JSON variables use the object resolver.

OpenFeature's targeting key maps to `userId` by default. `targetingKeyField`, `keySeparator`, `variationKey`, and `globalVariablePrefix` on `FeaturevisorOpenFeatureProvider.Options` can customize the mapping. The global variable prefix defaults to `variable` and cannot contain the configured separator.

2. Tag the release with a `v` prefix, such as `v4.0.0`, and push the tag.