Class AbstractDelegatingMarshaller

  • All Implemented Interfaces:
    Marshaller, StreamingMarshaller

    public abstract class AbstractDelegatingMarshaller
    extends Object
    implements StreamingMarshaller
    With the introduction of global and cache marshallers, there's a need to separate marshallers but still rely on the same marshalling backend as previously. So, this class acts as a delegator for the new marshallers.
    Since:
    5.0
    Author:
    Galder ZamarreƱo
    • Constructor Detail

      • AbstractDelegatingMarshaller

        public AbstractDelegatingMarshaller()
    • Method Detail

      • stop

        public void stop()
        Description copied from interface: StreamingMarshaller
        Stop the marshaller. Implementations of this method should clear up any cached data, or close any resources while marshalling/unmarshalling that have not been already closed.
        Specified by:
        stop in interface Marshaller
        Specified by:
        stop in interface StreamingMarshaller
      • startObjectOutput

        public ObjectOutput startObjectOutput​(OutputStream os,
                                              boolean isReentrant,
                                              int estimatedSize)
                                       throws IOException
        Description copied from interface: StreamingMarshaller

        Create and open an ObjectOutput instance for the given output stream. This method should be used for opening data outputs when multiple objectToObjectStream() calls will be made before the stream is closed by calling finishObjectOutput().

        This method also takes a boolean that represents whether this particular call to startObjectOutput() is reentrant or not. A call to startObjectOutput() should be marked reentrant whenever a 2nd or more calls to this method are made without having called finishObjectOutput() first.

        To potentially speed up calling startObjectOutput multiple times in a non-reentrant way, i.e. startObjectOutput/finishObjectOutput...startObjectOutput/finishObjectOutput...etc, which is is the most common case, the StreamingMarshaller implementation could potentially use some mechanisms to speed up this startObjectOutput call.

        On the other hand, when a call is reentrant, i.e. startObjectOutput/startObjectOutput(reentrant)...finishObjectOutput/finishObjectOutput, the StreamingMarshaller implementation might treat it differently. An example of reentrancy would be marshalling of MarshalledValue. When sending or storing a MarshalledValue, a call to startObjectOutput() would occur so that the stream is open and following, a 2nd call could occur so that MarshalledValue's raw byte array version is calculated and sent across. This enables storing as binary on the receiver side which is performance gain. The StreamingMarshaller implementation could decide that it needs a separate ObjectOutput or similar for the 2nd call since it's aim is only to get the raw byte array version and the close finish with it.

        Specified by:
        startObjectOutput in interface StreamingMarshaller
        Parameters:
        os - output stream
        isReentrant - whether the call is reentrant or not.
        estimatedSize - estimated size in bytes of the output. Only meant as a possible performance optimization.
        Returns:
        ObjectOutput to write to
        Throws:
        IOException
      • finishObjectOutput

        public void finishObjectOutput​(ObjectOutput oo)
        Description copied from interface: StreamingMarshaller
        Finish using the given ObjectOutput. After opening a ObjectOutput and calling objectToObjectStream() multiple times, use this method to flush the data and close if necessary
        Specified by:
        finishObjectOutput in interface StreamingMarshaller
        Parameters:
        oo - data output that finished using
      • startObjectInput

        public ObjectInput startObjectInput​(InputStream is,
                                            boolean isReentrant)
                                     throws IOException
        Description copied from interface: StreamingMarshaller

        Create and open a new ObjectInput for the given input stream. This method should be used for opening data inputs when multiple objectFromObjectStream() calls will be made before the stream is closed.

        This method also takes a boolean that represents whether this particular call to startObjectInput() is reentrant or not. A call to startObjectInput() should be marked reentrant whenever a 2nd or more calls to this method are made without having called finishObjectInput() first.

        To potentially speed up calling startObjectInput multiple times in a non-reentrant way, i.e. startObjectInput/finishObjectInput...startObjectInput/finishObjectInput...etc, which is is the most common case, the StreamingMarshaller implementation could potentially use some mechanisms to speed up this startObjectInput call.

        Specified by:
        startObjectInput in interface StreamingMarshaller
        Parameters:
        is - input stream
        isReentrant - whether the call is reentrant or not.
        Returns:
        ObjectInput to read from
        Throws:
        IOException
      • finishObjectInput

        public void finishObjectInput​(ObjectInput oi)
        Description copied from interface: StreamingMarshaller
        Finish using the given ObjectInput. After opening a ObjectInput and calling objectFromObjectStream() multiple times, use this method to flush the data and close if necessary
        Specified by:
        finishObjectInput in interface StreamingMarshaller
        Parameters:
        oi - data input that finished using
      • objectToByteBuffer

        public byte[] objectToByteBuffer​(Object obj,
                                         int estimatedSize)
                                  throws IOException,
                                         InterruptedException
        Description copied from interface: Marshaller
        Marshalls an object to a byte array. The estimatedSize parameter is a hint that can be passed in to allow for efficient sizing of the byte array before attempting to marshall the object. The more accurate this estimate is, the less likely byte[]s will need to be resized to hold the byte stream generated by marshalling the object.
        Specified by:
        objectToByteBuffer in interface Marshaller
        Parameters:
        obj - object to convert to a byte array. Must not be null.
        estimatedSize - an estimate of how large the resulting byte array may be
        Returns:
        a byte array with the marshalled form of the object
        Throws:
        IOException - if marshalling cannot complete due to some I/O error
        InterruptedException - if the marshalling was interrupted. Clients should take this as a sign that the marshaller is no longer available, maybe due to shutdown, and so no more unmarshalling should be attempted.
      • objectToByteBuffer

        public byte[] objectToByteBuffer​(Object obj)
                                  throws IOException,
                                         InterruptedException
        Description copied from interface: Marshaller
        Marshalls an object to a byte array.
        Specified by:
        objectToByteBuffer in interface Marshaller
        Parameters:
        obj - object to convert to a byte array. Must not be null.
        Returns:
        a byte array
        Throws:
        IOException - if marshalling cannot complete due to some I/O error
        InterruptedException - if the marshalling process was interrupted. Clients should take this as a sign that the marshaller is no longer available, maybe due to shutdown, and so no more marshalling should be attempted.
      • objectFromByteBuffer

        public Object objectFromByteBuffer​(byte[] buf,
                                           int offset,
                                           int length)
                                    throws IOException,
                                           ClassNotFoundException
        Description copied from interface: Marshaller
        Unmarshalls an object from a specific portion of a byte array.
        Specified by:
        objectFromByteBuffer in interface Marshaller
        Parameters:
        buf - byte array containing the binary representation of an object. Must not be null.
        offset - point in buffer to start reading
        length - number of bytes to consider
        Returns:
        an object
        Throws:
        IOException - if unmarshalling cannot complete due to some I/O error
        ClassNotFoundException - if the class of the object trying to unmarshall is unknown
      • objectToBuffer

        public ByteBuffer objectToBuffer​(Object o)
                                  throws IOException,
                                         InterruptedException
        Description copied from interface: Marshaller
        A method that returns an instance of ByteBuffer, which allows direct access to the byte array with minimal array copying
        Specified by:
        objectToBuffer in interface Marshaller
        Parameters:
        o - object to marshall
        Throws:
        IOException - if marshalling cannot complete due to some I/O error
        InterruptedException - if the marshalling process was interrupted. Clients should take this as a sign that the marshaller is no longer available, maybe due to shutdown, and so no more marshalling should be attempted.
      • isMarshallable

        public boolean isMarshallable​(Object o)
                               throws Exception
        Description copied from interface: Marshaller
        A method that checks whether the given object is marshallable as per the rules of this marshaller.
        Specified by:
        isMarshallable in interface Marshaller
        Parameters:
        o - object to verify whether it's marshallable or not
        Returns:
        true if the object is marshallable, otherwise false
        Throws:
        Exception - if while checking whether the object was serializable or not, an exception arose
      • getBufferSizePredictor

        public BufferSizePredictor getBufferSizePredictor​(Object o)
        Description copied from interface: Marshaller
        Returns a marshalled payload size predictor for a particular type. Accurate prediction of a type's serialized payload size helps avoid unnecessary copying and speeds up application performance.
        Specified by:
        getBufferSizePredictor in interface Marshaller
        Parameters:
        o - Object for which serialized predictor will be returned
        Returns:
        an instance of BufferSizePredictor