org.knime.core.data.container
Class DCObjectInputVersion2

java.lang.Object
  org.knime.core.data.container.DCObjectInputVersion2

All Implemented Interfaces:

KNIMEStreamConstants

final class DCObjectInputVersion2
extends Object
implements KNIMEStreamConstants

Class interpreting the file format as written by the Buffer class. It supports both modes of DataCell serialization, that is using a DataCellSerializer and a plain java serialization.

This class is the counterpart to DCObjectOutputVersion2, see details on the file format in there.

Author:

Bernd Wiswedel, University of Konstanz

Field Summary

Fields inherited from interface org.knime.core.data.container.KNIMEStreamConstants

BYTE_ROW_SEPARATOR, BYTE_TYPE_MISSING, BYTE_TYPE_SERIALIZATION, BYTE_TYPE_START, DUMMY_ROW_KEY, TC_ESCAPE, TC_TERMINATE

Constructor Summary

DCObjectInputVersion2(InputStream in, BufferFromFileIteratorVersion20.DataCellStreamReader cellReader)
Creates new input stream that reads from in.

Method Summary

(package private) void	close() Closes the underlying streams.
(package private) void	endBlock() Pushes the stream forth until a mark is encountered.
(package private) BlobDataCell.BlobAddress	readBlobAddress() Reads a blob address from the stream.
(package private) byte	readControlByte() Reads a single byte from the stream.
(package private) DataCell	readDataCellPerJavaSerialization() Reads a data cell from the stream using java de-serialization.
(package private) DataCell	readDataCellPerKNIMESerializer(DataCellSerializer<? extends DataCell> serializer) Reads a data cell from the stream.
(package private) RowKey	readRowKey() Reads a row key from the stream.
(package private) void	setCurrentClassLoader(ClassLoader l) Set the class loader to ask "first" to load classes.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DCObjectInputVersion2

DCObjectInputVersion2(InputStream in,
                      BufferFromFileIteratorVersion20.DataCellStreamReader cellReader)

Creates new input stream that reads from in.

Parameters:

in - The stream to read from.

cellReader - The object that helps to read DataCell contained in DataCell as required by DataCellDataInput.readDataCell().

Method Detail

readDataCellPerKNIMESerializer

DataCell readDataCellPerKNIMESerializer(DataCellSerializer<? extends DataCell> serializer)
                                  throws IOException

Reads a data cell from the stream.

Parameters:

serializer - The factory that is used to create the cell

Returns:

A new data cell instance.

Throws:

IOException - If reading fails.

See Also:

DataCellSerializer.deserialize(DataCellDataInput)

readDataCellPerJavaSerialization

DataCell readDataCellPerJavaSerialization()
                                    throws IOException

Reads a data cell from the stream using java de-serialization.

Returns:

A new data cell instance.

Throws:

IOException - If reading fails (also e.g. ClassCastException are wrapped in such IO exceptions).

readBlobAddress

BlobDataCell.BlobAddress readBlobAddress()
                                   throws IOException

Reads a blob address from the stream.

Returns:

as read from the stream.

Throws:

IOException - If that fails.

readRowKey

RowKey readRowKey()
            throws IOException

Reads a row key from the stream.

Returns:

A new row key instance.

Throws:

IOException - If IO problems occur.

readControlByte

byte readControlByte()
               throws IOException

Reads a single byte from the stream.

Returns:

That byte.

Throws:

IOException - If IO problems occur.

endBlock

void endBlock()
        throws IOException

Pushes the stream forth until a mark is encountered.

Throws:

IOException - If IO problems occur.

setCurrentClassLoader

void setCurrentClassLoader(ClassLoader l)

Set the class loader to ask "first" to load classes. Used when a data cell is deserialized and all its member should be loaded in the context of that class loader.

Parameters:

l - The class loader to use, if null it uses the globally known class loader (GlobalClassCreator)

close

void close()
     throws IOException

Closes the underlying streams.

Throws:

IOException - If underlying streams fail to close.