Class EXTDTAInputStream

java.lang.Object

java.io.InputStream

org.apache.derby.impl.drda.EXTDTAInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

class EXTDTAInputStream
extends InputStream

EXTDTAObjectHolder provides Externalized Large Object representation that does not hold locks until the end of the transaction (DERBY-255) It serves as a holder for lob data and is only valid as long as the original result set from which it came is on the same row.

Field Summary

Fields

Modifier and Type	Field	Description
private Blob	_blob
private Clob	_clob
private InputStream	binaryInputStream
(package private) int	columnNumber	Column index starting with 1
(package private) int	ndrdaType	DRDA Type of column/parameter
(package private) EngineResultSet	rs	ResultSet that contains the stream

Constructor Summary

Constructors

Modifier	Constructor	Description
private	EXTDTAInputStream(Blob blob, int ndrdaType)
private	EXTDTAInputStream(Clob clob, int ndrdaType)
private	EXTDTAInputStream(ResultSet rs, int columnNumber, int ndrdaType)

Method Summary

Modifier and Type	Method	Description
int	available()
private static void	badDRDAType(int drdaType)
void	close()
boolean	equals(Object arg0)
protected void	finalize()
private InputStream	getBinaryStream()
private Reader	getCharacterStream()
static EXTDTAInputStream	getEXTDTAStream(CallableStatement cs, int column, int drdaType)	Create a new EXTDTAInputStream from a CallableStatement.
static EXTDTAInputStream	getEXTDTAStream(ResultSet rs, int column, int drdaType)	Create a new EXTDTAInputStream.
int	hashCode()
void	initInputStream()	This method takes information of ResultSet and initializes the binaryInputStream variable of this object with not empty stream by calling getBinaryStream or getCharacterStream() as appropriate.
protected boolean	isEmptyStream()
boolean	isNull()	Is the value null?
private long	length()
void	mark(int arg0)
boolean	markSupported()
int	read()	Requires initInputStream() be called before we can read from the stream
int	read(byte[] arg0)
int	read(byte[] arg0, int arg1, int arg2)
void	reset()
long	skip(long arg0)

Methods inherited from class InputStream

nullInputStream, readAllBytes, readNBytes, readNBytes, skipNBytes, transferTo

Methods inherited from class Object

clone, getClass, notify, notifyAll, toString, wait, wait, wait

Field Details

binaryInputStream

private InputStream binaryInputStream

ndrdaType

int ndrdaType

DRDA Type of column/parameter

rs

EngineResultSet rs

ResultSet that contains the stream

columnNumber

int columnNumber

Column index starting with 1

_clob

private Clob _clob

_blob

private Blob _blob

Constructor Details

EXTDTAInputStream

private EXTDTAInputStream(ResultSet rs,
 int columnNumber,
 int ndrdaType)

EXTDTAInputStream

private EXTDTAInputStream(Clob clob,
 int ndrdaType)

EXTDTAInputStream

private EXTDTAInputStream(Blob blob,
 int ndrdaType)

Method Details

getEXTDTAStream

public static EXTDTAInputStream getEXTDTAStream(ResultSet rs,
 int column,
 int drdaType)

Create a new EXTDTAInputStream. Before read the stream must be initialized by the user with initInputStream()

Parameters:

rs - result set from which to retrieve the lob

column - column number

drdaType - FD:OCA type of object one of DRDAConstants.DRDA_TYPE_NLOBBYTES DRDAConstants.DRDA_TYPE_LOBBYTES DRDAConstants.DRDA_TYPE_NLOBCMIXED DRDAConstants.DRDA_TYPE_LOBCMIXED

Returns:

null if the value is null or a new EXTDTAInputStream corresponding to rs.getBinaryStream(column) value and associated length

Throws:

SQLException

See Also:

• DDMWriter.writeScalarStream(boolean, int, EXTDTAInputStream, boolean)
• initInputStream()

getEXTDTAStream

public static EXTDTAInputStream getEXTDTAStream(CallableStatement cs,
 int column,
 int drdaType)
                                         throws SQLException

Create a new EXTDTAInputStream from a CallableStatement.

Parameters:

cs - CallableStatement from which to retrieve the lob

column - column number

drdaType - FD:OCA type of object one of DRDAConstants.DRDA_TYPE_NLOBBYTES DRDAConstants.DRDA_TYPE_LOBBYTES DRDAConstants.DRDA_TYPE_NLOBCMIXED DRDAConstants.DRDA_TYPE_LOBCMIXED

Throws:

SQLException

read

public int read()
         throws IOException

Requires initInputStream() be called before we can read from the stream

Specified by:

read in class InputStream

Throws:

IOException

See Also:

• InputStream.read()

available

public int available()
              throws IOException

Overrides:

available in class InputStream

Throws:

IOException

See Also:

• InputStream.available()

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class InputStream

Throws:

IOException

See Also:

• InputStream.close()

equals

public boolean equals(Object arg0)

Overrides:

equals in class Object

See Also:

• Object.equals(java.lang.Object)

hashCode

public int hashCode()

Overrides:

hashCode in class Object

See Also:

• Object.hashCode()

mark

public void mark(int arg0)

Overrides:

mark in class InputStream

See Also:

• InputStream.mark(int)

markSupported

public boolean markSupported()

Overrides:

markSupported in class InputStream

See Also:

• InputStream.markSupported()

read

public int read(byte[] arg0)
         throws IOException

Overrides:

read in class InputStream

Throws:

IOException

See Also:

• InputStream.read(byte[])

read

public int read(byte[] arg0,
 int arg1,
 int arg2)
         throws IOException

Overrides:

read in class InputStream

Throws:

IOException

See Also:

• InputStream.read(byte[], int, int)

reset

public void reset()
           throws IOException

Overrides:

reset in class InputStream

Throws:

IOException

See Also:

• InputStream.reset()

skip

public long skip(long arg0)
          throws IOException

Overrides:

skip in class InputStream

Throws:

IOException

See Also:

• InputStream.skip(long)

isEmptyStream

protected boolean isEmptyStream()
                         throws SQLException

Throws:

SQLException

length

private long length()
             throws SQLException

Throws:

SQLException

initInputStream

public void initInputStream()
                     throws SQLException

This method takes information of ResultSet and initializes the binaryInputStream variable of this object with not empty stream by calling getBinaryStream or getCharacterStream() as appropriate. The Reader returned from getCharacterStream() will be encoded in binarystream.

Throws:

SQLException

getBinaryStream

private InputStream getBinaryStream()
                             throws SQLException

Throws:

SQLException

getCharacterStream

private Reader getCharacterStream()
                           throws SQLException

Throws:

SQLException

badDRDAType

private static void badDRDAType(int drdaType)

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable

isNull

public boolean isNull()
               throws SQLException

Is the value null? Null status is obtained from the underlying EngineResultSet or LOB, so that it can be determined before the stream is retrieved.

Returns:

true if this value is null

Throws:

SQLException