Package com.tangosol.coherence.servlet

Class SplittableHolder

  • All Implemented Interfaces:
    ExternalizableLite, Externalizable, Serializable
    public class SplittableHolder
extends OptimizedHolder
    An immutable object to hold attribute values and related information. In this AttributeHolder sub-class, the binary value will be null if it has not been serialized, empty if it is external and has not been fetched yet, or a valid binary value.
    See Also:
    Serialized Form

    • Constructor Detail

      • SplittableHolder

        public SplittableHolder()
        Default constructor for ExternalizableLite.

      • SplittableHolder

        public SplittableHolder​(SplitHttpSessionModel model)
        Construct an AttributeHolder for a value.
        Parameters:
        model - the split http session model

      • SplittableHolder

        public SplittableHolder​(String sName,
                        Object oValue,
                        SplitHttpSessionModel model)
        Construct an AttributeHolder for a value.
        Parameters:
        sName - the attribute name
        oValue - the value of the attribute; not null
        model - the split http session model

    • Method Detail

      • getValue

        public Object getValue()
        Obtain the object form of the value.
        Overrides:
        getValue in class OptimizedHolder
        Returns:
        the object form of the value

      • onBound

        public void onBound​(AttributeHolder holderOrig)
        Called when the attribute is bound.
        Overrides:
        onBound in class AttributeHolder
        Parameters:
        holderOrig - the holder that this new bound holder is replacing, if any, otherwise null

      • onUnbound

        public void onUnbound​(boolean fReplaced,
                      boolean fAll)
        Called when the attribute is unbound.
        Overrides:
        onUnbound in class AttributeHolder
        Parameters:
        fReplaced - set to true of this is the result of a bind operation (so the holder is being replaced)
        fAll - true if this method is called within the context of an AbstractHttpSessionModel.unbind() call

      • ensureInternalBinary

        protected Binary ensureInternalBinary()
        Obtain the non-null internally managed binary value. This method allows sub-classes to lazily load the cached binary.

        This method is explicitly NOT a "MAKE BINARY OUT OF VALUE" method. It is only intended to allow lazy loading of the pre-existing binary value, for example from a distributed cache.

        Overrides:
        ensureInternalBinary in class OptimizedHolder
        Returns:
        the binary form of the value, but never null

      • isExternal

        protected boolean isExternal()
        Determine if the value is stored in the external cache. The value in the external cache is not necessarily up to date; this only indicates whether it is there at all.
        Returns:
        true if the holder's value is stored in the external cache

      • setExternal

        protected void setExternal​(boolean fExternal)
        Specify that the value is stored in the external cache.
        Parameters:
        fExternal - true if the object is stored in the external cache

      • isExternalDesirable

        protected boolean isExternalDesirable​(Binary binValue)
        Decide whether or not this holder will choose to store the passed binary value in its external storage.
        Parameters:
        binValue - the binary value to evaluate to determine whether it should be stored internally or externally
        Returns:
        true if this holder will store the passed value in an external cache, false otherwise

      • getExternalKey

        protected Object getExternalKey()
        Build a key that will be used to access the binary value for this attribute holder that in the external cache.
        Returns:
        the key for this attribute holder's value in the external cache

      • assignExternalKey

        protected Object assignExternalKey​(String sId)
        Generate and set the key that will be used to access the binary value for this attribute holder that is in the external cache.
        Parameters:
        sId - the session ID associated with this key
        Returns:
        the key for this attribute holder's value in the external cache

      • getExternalBinary

        protected Binary getExternalBinary()
        Obtain the binary form of the value from the external cache.
        Returns:
        the binary form of the value or null if it hasn't been stored in the external cache yet

      • getExternalValue

        protected Object getExternalValue()
        Obtain the value from the external cache. For a session with a large Binary value that is split into multiple segments, its value is the key set of the split segments. Otherwise, the value is Binary and this method returns null.
        Returns:
        the value of the session if the value of the session is split into multiple segments, or null if the value is in binary form.
        Since:
        12.2.1.4.16

      • setExternalBinary

        protected void setExternalBinary​(Binary binValue)
        Store the binary form of the value in the external cache.
        Parameters:
        binValue - the binary form of the value to store in the external cache

      • removeExternalBinary

        protected void removeExternalBinary()
        Remove the binary form of the value from the external cache.

      • prepareWrite

        protected void prepareWrite()
                     throws IOException
        Called to test serialization; if the holder cannot serialize its value, it should throw an IOException at this point. Note that this method should only be called as part of the "write" processing for the model, as the holder will expect an immediate follow-up call to actually write itself out.
        Overrides:
        prepareWrite in class OptimizedHolder
        Throws:
        IOException - if the holder cannot serialize its value

      • readBinary

        protected Binary readBinary​(DataInput in)
                     throws IOException
        Read the binary value. This is part of deserialization processing, and is separated out to enable subclassing.
        Overrides:
        readBinary in class OptimizedHolder
        Parameters:
        in - the DataInput that this holder is being deserialized from
        Returns:
        the binary value
        Throws:
        IOException - on I/O error

      • writeBinary

        protected void writeBinary​(DataOutput out)
                    throws IOException
        Write the binary value. This is part of serialization processing, and is separated out to enable subclassing.
        Overrides:
        writeBinary in class OptimizedHolder
        Parameters:
        out - the DataOutput that this holder is being serialized to
        Throws:
        IOException - on I/O error

      • isInstanceOfElasticKeys

        protected static boolean isInstanceOfElasticKeys​(Object object)
        Determine if a given object is an ElasticKey or a collection of ElasticKeys.
        Parameters:
        object - the object
        Returns:
        true if the given object is of the ElasticKey type or its collection; false otherwise
        Since:
        12.2.1.4.16