public String getEntityIdKey() {
        return this.entityIdKey;
    }
<p>
The entity, such as a user or session, that does an action that causes a metric value to be recorded.
</p>

@return The entity, such as a user or session, that does an action that causes a metric value to be recorded.
aws-java-sdk-cloudwatchevidently/src/main/java/com/amazonaws/services/cloudwatchevidently/model/MetricDefinition.java