In-App purchasing demo

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 #ifndef ANDROIDINAPPPURCHASEBACKEND_H
 #define ANDROIDINAPPPURCHASEBACKEND_H

 #include <QMutex>
 #include <QSet>
 #include <QDateTime>
 #include <QJniObject>
 #include <QJniEnvironment>

 #include "../inapp/inapppurchasebackend.h"
 #include "../inapp/inappproduct.h"
 #include "../inapp/inapptransaction.h"

 class AndroidInAppProduct;
 class AndroidInAppPurchaseBackend : public InAppPurchaseBackend
 {
     Q_OBJECT
 public:
     explicit AndroidInAppPurchaseBackend(QObject *parent = 0);

     void initialize();
     bool isReady() const;

     void queryProducts(const QList<Product> &products);
     void queryProduct(InAppProduct::ProductType productType, const QString &identifier);
     void restorePurchases();

     void setPlatformProperty(const QString &propertyName, const QString &value);

     void purchaseProduct(AndroidInAppProduct *product);

     void consumeTransaction(const QString &purchaseToken);
     void registerFinalizedUnlockable(const QString &identifier);

     // Callbacks from Java
     Q_INVOKABLE void registerProduct(const QString &productId,
                                      const QString &price,
                                      const QString &title,
                                      const QString &description);
     Q_INVOKABLE void registerPurchased(const QString &identifier,
                                        const QString &signature,
                                        const QString &data,
                                        const QString &purchaseToken,
                                        const QString &orderId,
                                        const QDateTime &timestamp);
     Q_INVOKABLE void purchaseSucceeded(int requestCode,
                                        const QString &signature,
                                        const QString &data,
                                        const QString &purchaseToken,
                                        const QString &orderId,
                                        const QDateTime &timestamp);
     Q_INVOKABLE void purchaseFailed(int requestCode,
                                     int failureReason,
                                     const QString &errorString);
     Q_INVOKABLE void registerReady();

 private:
     void checkFinalizationStatus(InAppProduct *product,
                                  InAppTransaction::TransactionStatus status = InAppTransaction::PurchaseApproved);
     bool transactionFinalizedForProduct(InAppProduct *product);
     void purchaseFailed(InAppProduct *product,
                         int failureReason,
                         const QString &errorString);

     struct PurchaseInfo
     {
         PurchaseInfo(const QString &signature_, const QString &data_, const QString &purchaseToken_, const QString &orderId_, const QDateTime &timestamp_)
             : signature(signature_)
             , data(data_)
             , purchaseToken(purchaseToken_)
             , orderId(orderId_)
             , timestamp(timestamp_)
         {
         }

         QString signature;
         QString data;
         QString purchaseToken;
         QString orderId;
         QDateTime timestamp;
     };

     mutable QRecursiveMutex m_mutex;
     bool m_isReady;
     QList<QString> purchasedUnlockebles;
     QJniObject m_javaObject;
     QScopedPointer<AndroidInAppPurchaseBackend> d;
     QHash<QString, InAppProduct::ProductType> m_productTypeForPendingId;
     QHash<QString, PurchaseInfo> m_infoForPurchase;
     QHash<int, InAppProduct *> m_activePurchaseRequests;
 };

 #endif // ANDROIDINAPPPURCHASEBACKEND_H