||Represents the result of an attempt to retrieve existing purchases.
||Interface for listening for the results of retrieving
PaymentEngine information asynchronously.
||Handles generic failures of asynchronous calls to the payment engine.
||Class that encapsulates a set of string values representing prices for subscription goods with
the set of tags to retrieve them.
||Represents a successful in-app purchase.
||Represents the result of an in-app purchase attempt.
||Represents the result of a payment-related transaction attempt, such as making an in-app purchase
or retrieving existing purchases.
||Constants returned from
PaymentException.getFailureReason() when a call fails.