# Variation Distribution When running an A/B Test, you need to assign users to Variations and implement logic for each Variation. You can use the Hackle SDK to handle this user distribution. ## variation {% hint style="info" %} When using the Java/Kotlin SDK, duplicate exposure events for the same A/B Test distribution result triggered consecutively by the same user within 1 minute are removed. Events within 1 minute are counted as 1 occurrence. {% endhint %} {% hint style="warning" %} Cohort Targeting is not supported in the Server SDK.\ If the Targeting includes a cohort, please run the test using the Client SDK. {% endhint %} Pass the **Experiment Key** and **User Identifier** to the `variation()` method to assign users to a Variation and receive the result. Then implement logic for each Variation. In the example code below, Experiment Key 42 is passed and the User Identifier is "ae2182e0". There are two Variations: A and B. {% tabs %} {% tab title="Kotlin" %} ```kotlin import io.hackle.sdk.HackleClient import io.hackle.sdk.common.Variation // Determines which Variation to show to the user identified as "ae2182e0" // in the A/B Test with Experiment Key 42. // Returns Variation A if a decision cannot be made. val variation: Variation = hackleClient.variation(42, "ae2182e0") // Logic for the assigned Variation if (variation == Variation.A) { // Group A logic } else if (variation == Variation.B) { // Group B logic } ``` {% endtab %} {% tab title="Java" %} ```java import io.hackle.sdk.HackleClient import io.hackle.sdk.common.Variation // Determines which Variation to show to the user identified as "ae2182e0" // in the A/B Test with Experiment Key 42. // Returns Variation A if a decision cannot be made. Variation variation = hackleClient.variation(42, "ae2182e0"); // Logic for the assigned Variation if (variation == Variation.A) { // Group A logic } else if (variation == Variation.B) { // Group B logic } ``` {% endtab %} {% endtabs %} ## variationDetail The `variationDetail()` method works the same as `variation()` but additionally provides the reason for being assigned to a specific group. This method is useful for verifying that distribution is working correctly.\ You must pass the Experiment Key as a parameter. In the example code below, Experiment Key 42 is passed. {% tabs %} {% tab title="Kotlin" %} ```kotlin import io.hackle.sdk.HackleClient import io.hackle.sdk.common.Variation import io.hackle.sdk.common.decision.Decision import io.hackle.sdk.common.decision.DecisionReason // Variation distribution decision detail val decision: Decision = hackleClient.variationDetail(42, "ae2182e0") // Assigned Variation val variation: Variation = decision.variation // Decision reason val reason: DecisionReason = decision.reason ``` {% endtab %} {% tab title="Java" %} ```java import io.hackle.sdk.HackleClient import io.hackle.sdk.common.Variation import io.hackle.sdk.common.decision.Decision import io.hackle.sdk.common.decision.DecisionReason // Variation distribution decision detail Decision decision = hackleClient.variationDetail(42, "ae2182e0"); // Assigned Variation Variation variation = decision.getVariation(); // Decision reason DecisionReason reason = decision.getReason(); ``` {% endtab %} {% endtabs %} The decision reason is returned in a format such as **`SDK_NOT_READY`**. Refer to the table below for details.
Distribution ReasonDescriptionDistribution Result
SDK_NOT_READY

The SDK is not ready to use.

(e.g., initialization attempted with an invalid SDK Key)

A (Control Group)
EXPERIMENT_NOT_FOUNDNo A/B Test was found for the provided Experiment Key. The Experiment Key may be incorrect, or the experiment may be archived.A (Control Group)
NOT_IN_MUTUAL_EXCLUSION_EXPERIMENTThe experiment is included in Mutually Exclusive Settings, but
the user was not assigned to that Mutually Exclusive Group.		A (Control Group)
EXPERIMENT_DRAFTThe A/B Test is in draft state.A (Control Group)
EXPERIMENT_PAUSEDThe A/B Test is paused.A (Control Group)
EXPERIMENT_COMPLETEDThe A/B Test has ended.Winning Variation selected at completion
OVERRIDDENThe user was assigned to a specific group
by Override.		Override-assigned
group
NOT_IN_EXPERIMENT_TARGETThe user is not an A/B Test target.A (Control Group)
TRAFFIC_NOT_ALLOCATEDThe A/B Test is running, but
the user was not allocated to the test.		A (Control Group)
TRAFFIC_ALLOCATEDThe user has been allocated to the A/B Test.Allocated group
VARIATION_DROPPEDThe originally allocated group has been removed from the test.A (Control Group)
INVALID_INPUTThe input value is invalid.A (Control Group)
EXCEPTIONAn unknown error occurred.A (Control Group)
## Parameters * You can also receive the parameter values for the assigned Variation through the `variationDetail()` method. * The `Decision` instance returned by `variationDetail()` contains a `ParameterConfig` object with the full parameter configuration. * Since parameter values configured in the Hackle A/B Test screen are stored as key-value pairs, use the methods below according to the parameter type to retrieve the configured values. {% tabs %} {% tab title="Kotlin" %} #### getString * Returns parameter values configured as STRING or JSON type. * Returns the value configured for the assigned Variation. ```kotlin import io.hackle.sdk.HackleClient import io.hackle.sdk.common.decision.Decision import io.hackle.sdk.common.decision.DecisionReason val decision: Decision = hackleClient.variationDetail(42, "ae2182e0") val config: ParameterConfig = decision.config val strValue: String = decision.getString("parameter_key_string_type", "defaultValue") val strValueInConfig: String = config.getString("parameter_key_string_type", "defaultValue") val jsonValue: String = decision.getString("parameter_key_json_type", "defaultValue") val jsonValueInConfig: String = config.getString("parameter_key_json_type", "defaultValue") ``` #### getInt * Returns parameter values configured as Number type as an Int. * Returns the value configured for the assigned Variation. ```kotlin import io.hackle.sdk.HackleClient import io.hackle.sdk.common.decision.Decision val decision: Decision = hackleClient.variationDetail(42, "ae2182e0") val config: ParameterConfig = decision.config val intValue: Int = decision.getInt("parameter_key_number_type", 0) val intValueInConfig: Int = config.getInt("parameter_key_number_type", 0) ``` #### getDouble * Returns parameter values configured as Number type as a Double. * Returns the value configured for the assigned Variation. ```kotlin import io.hackle.sdk.HackleClient import io.hackle.sdk.common.decision.Decision val decision: Decision = hackleClient.variationDetail(42, "ae2182e0") val config: ParameterConfig = decision.config val doubleValue: Double = decision.getDouble("parameter_key_number_type", 0.0) val doubleValueInConfig: Double = config.getDouble("parameter_key_number_type", 0.0) ``` #### getLong * Returns parameter values configured as Number type as a Long. * Returns the value configured for the assigned Variation. ```kotlin import io.hackle.sdk.HackleClient import io.hackle.sdk.common.decision.Decision val decision: Decision = hackleClient.variationDetail(42, "ae2182e0") val config: ParameterConfig = decision.config val longValue: Long = decision.getLong("parameter_key_number_type", 0L) val longValueInConfig: Long = config.getLong("parameter_key_number_type", 0L) ``` #### getBoolean * Returns parameter values configured as Boolean type. * Returns the value configured for the assigned Variation. ```kotlin import io.hackle.sdk.HackleClient import io.hackle.sdk.common.decision.Decision val decision: Decision = hackleClient.variationDetail(42, "ae2182e0") val config: ParameterConfig = decision.config val booleanValue: Boolean = decision.getBoolean("parameter_key_boolean_type", false) val booleanValueInConfig: Boolean = config.getBoolean("parameter_key_boolean_type", false) ``` {% endtab %} {% tab title="Java" %} #### getString * Returns parameter values configured as STRING or JSON type. * Returns the value configured for the assigned Variation. ```java import io.hackle.sdk.HackleClient import io.hackle.sdk.common.decision.Decision import io.hackle.sdk.common.decision.DecisionReason Decision decision = hackleClient.variationDetail(42, "ae2182e0"); ParameterConfig config = decision.getConfig(); String strValue = decision.getString("parameter_key_string_type", "defaultValue"); String strValueInConfig = config.getString("parameter_key_string_type", "defaultValue"); String jsonValue = decision.getString("parameter_key_json_type", "defaultValue"); String jsonValueInConfig = config.getString("parameter_key_json_type", "defaultValue"); ``` #### getInt * Returns parameter values configured as Number type as an Int. * Returns the value configured for the assigned Variation. ```java import io.hackle.sdk.HackleClient import io.hackle.sdk.common.decision.Decision Decision decision = hackleClient.variationDetail(42, "ae2182e0"); ParameterConfig config = decision.getConfig(); int intValue = decision.getInt("parameter_key_number_type", 0); int intValueInConfig = config.getInt("parameter_key_number_type", 0); ``` #### getDouble * Returns parameter values configured as Number type as a Double. * Returns the value configured for the assigned Variation. ```java import io.hackle.sdk.HackleClient import io.hackle.sdk.common.decision.Decision Decision decision = hackleClient.variationDetail(42, "ae2182e0"); ParameterConfig config = decision.getConfig(); double doubleValue = decision.getDouble("parameter_key_number_type", 0.0); double doubleValueInConfig = config.getDouble("parameter_key_number_type", 0.0); ``` #### getLong * Returns parameter values configured as Number type as a Long. * Returns the value configured for the assigned Variation. ```java import io.hackle.sdk.HackleClient import io.hackle.sdk.common.decision.Decision Decision decision = hackleClient.variationDetail(42, "ae2182e0"); ParameterConfig config = decision.getConfig(); long longValue = decision.getLong("parameter_key_number_type", 0L); long longValueInConfig = config.getLong("parameter_key_number_type", 0L); ``` #### getBoolean * Returns parameter values configured as Boolean type. * Returns the value configured for the assigned Variation. ```java import io.hackle.sdk.HackleClient import io.hackle.sdk.common.decision.Decision Decision decision = hackleClient.variationDetail(42, "ae2182e0"); ParameterConfig config = decision.getConfig(); boolean booleanValue = decision.getBoolean("parameter_key_boolean_type", false); boolean booleanValueInConfig = config.getBoolean("parameter_key_boolean_type", false); ``` {% endtab %} {% endtabs %} --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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