Interface ReplicatedMapEntry

  • All Superinterfaces:
    Serializable
    All Known Implementing Classes:
    DeltaSession

    public interface ReplicatedMapEntry
    extends Serializable
    For smarter replication, an object can implement this interface to replicate diffs
    The replication logic will call the methods in the following order:
    1. if ( entry.isDirty() )
    try { 2. entry.lock();
    3. byte[] diff = entry.getDiff();
    4. entry.reset();
    } finally {
    5. entry.unlock();
    }
    }


    When the data is deserialized the logic is called in the following order
    1. ReplicatedMapEntry entry = (ReplicatedMapEntry)objectIn.readObject();
    2. if ( isBackup(entry)||isPrimary(entry) ) entry.setOwner(owner);

    Version:
    1.0
    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      void accessEntry()
      Access to an existing object.
      void applyDiff​(byte[] diff, int offset, int length)
      Applies a diff to an existing object.
      byte[] getDiff()
      Returns a diff and sets the dirty map to false
      long getLastTimeReplicated()  
      long getVersion()
      For accuracy checking, a serialized attribute can contain a version number This number increases as modifications are made to the data.
      boolean isAccessReplicate()
      If this returns true, to replicate that an object has been accessed
      boolean isDiffable()
      If this returns true, the map will extract the diff using getDiff() Otherwise it will serialize the entire object.
      boolean isDirty()
      Has the object changed since last replication and is not in a locked state
      void lock()
      Lock during serialization
      void resetDiff()
      Resets the current diff state and resets the dirty flag
      void setLastTimeReplicated​(long lastTimeReplicated)
      Set the last replicate time.
      void setOwner​(Object owner)
      This method is called after the object has been created on a remote map.
      void setVersion​(long version)
      Forces a certain version to a replicated map entry
      void unlock()
      Unlock after serialization
    • Method Detail

      • isDirty

        boolean isDirty()
        Has the object changed since last replication and is not in a locked state
        Returns:
        boolean
      • isDiffable

        boolean isDiffable()
        If this returns true, the map will extract the diff using getDiff() Otherwise it will serialize the entire object.
        Returns:
        boolean
      • getDiff

        byte[] getDiff()
                throws IOException
        Returns a diff and sets the dirty map to false
        Returns:
        Serialized diff data
        Throws:
        IOException - IO error serializing
      • resetDiff

        void resetDiff()
        Resets the current diff state and resets the dirty flag
      • lock

        void lock()
        Lock during serialization
      • unlock

        void unlock()
        Unlock after serialization
      • setOwner

        void setOwner​(Object owner)
        This method is called after the object has been created on a remote map. On this method, the object can initialize itself for any data that wasn't
        Parameters:
        owner - Object
      • getVersion

        long getVersion()
        For accuracy checking, a serialized attribute can contain a version number This number increases as modifications are made to the data. The replicated map can use this to ensure accuracy on a periodic basis
        Returns:
        long - the version number or -1 if the data is not versioned
      • setVersion

        void setVersion​(long version)
        Forces a certain version to a replicated map entry
        Parameters:
        version - long
      • getLastTimeReplicated

        long getLastTimeReplicated()
        Returns:
        the last replicate time.
      • setLastTimeReplicated

        void setLastTimeReplicated​(long lastTimeReplicated)
        Set the last replicate time.
        Parameters:
        lastTimeReplicated - New timestamp
      • isAccessReplicate

        boolean isAccessReplicate()
        If this returns true, to replicate that an object has been accessed
        Returns:
        boolean
      • accessEntry

        void accessEntry()
        Access to an existing object.