Package com.helger.dao

Interface IDAO

  • All Superinterfaces:
    IAutoSaveAware
    All Known Implementing Classes:
    AbstractDAO, AbstractMapBasedWALDAO, AbstractSimpleDAO, AbstractWALDAO
    public interface IDAO
extends IAutoSaveAware
    Base DAO interface. DAO = Data Access Object. A DAO implementation usually has 3 basic operations:
    • Initialization - when no file exists and an initial setup can be performed.
    • Reading - read existing data from a file
    • Write - write modified data to a file
    Author:
    Philip Helger

    • Method Detail

      • hasPendingChanges

        boolean hasPendingChanges()
        Returns:
        true if there are pending changes, false if the content is unchanged.

      • writeToFileOnPendingChanges

        void writeToFileOnPendingChanges()
        This method is called to persist the content in disk in case there are pending changes. If no pending changes are present, nothing happens. In case the implementation is thread-safe, this method must be thread-safe!

      • getInitCount

        @Nonnegative
int getInitCount()
        Returns:
        The number of times this DAO was initialized. Always ≥ 0. Usually this field is not persistent and only is valid until the application ends.

      • getLastInitDateTime

        @Nullable
LocalDateTime getLastInitDateTime()
        Returns:
        The last time this DAO was initialized (without error). May be null if it wasn't read before. Usually this field is not persistent and only is valid until the application ends.

      • getReadCount

        @Nonnegative
int getReadCount()
        Returns:
        The number of times this DAO was initialized. Always ≥ 0. Usually this field is not persistent and only is valid until the application ends.

      • getLastReadDateTime

        @Nullable
LocalDateTime getLastReadDateTime()
        Returns:
        The last time this DAO was read (without error). May be null if it wasn't read before. Usually this field is not persistent and only is valid until the application ends.

      • getWriteCount

        @Nonnegative
int getWriteCount()
        Returns:
        The number of times this DAO was initialized. Always ≥ 0. Usually this field is not persistent and only is valid until the application ends.

      • getLastWriteDateTime

        @Nullable
LocalDateTime getLastWriteDateTime()
        Returns:
        The last time this DAO was written (without error). May be null if it wasn't written before. Usually this field is not persistent and only is valid until the application ends.

      • isReloadable

        default boolean isReloadable()
        Returns:
        true if this DAO support re-loading, false otherwise.
        See Also:
        reload()

      • reload

        default void reload()
             throws DAOException
        The method that is invoke if a DAO is reloaded. This method is only triggered if this DAO indicates that it is reloadable via isReloadable().
        Throws:
        DAOException - In case reloading fails