Apache Derby Network Server 10.17.1.0 · org.apache.derby.impl.drda.DDMWriter

Modifier and Type	Field and Description
private DRDAConnThread	agent
private ByteBuffer	buffer Output buffer.
private CcsidManager	ccsidManager
private int	correlationID
private static final int	DEFAULT_BUFFER_SIZE
private int	dssLengthLocation
private DssTrace	dssTrace
private EbcdicCcsidManager	ebcdicCcsidManager
private final CharsetEncoder	encoder Encoder which encodes strings with the server's default encoding.
private boolean	isContinuationDss
private boolean	isDRDAProtocol
private int	lastDSSBeforeMark
private int[]	markStack
private static final int	MAX_MARKS_NESTING
pack-priv static final int	MAX_VARCHAR_BYTE_LENGTH The maximum length in bytes for strings sent by `writeLDString()`, which is the maximum unsigned integer value that fits in two bytes.
private int	nextCorrelationID
private int	prevHdrLocation
private byte	previousChainByte
private int	previousCorrId
private int	top
pack-priv volatile long	totalByteCount
private Utf8CcsidManager	utf8CcsidManager

Access	Constructor and Description
pack-priv	DDMWriter(DRDAConnThread agent, DssTrace dssTrace)

Method Summary

Modifier and Type	Method and Description
private void	beginDss(boolean chainedToNextStructure, int dssType) Begins a DSS stream (for writing LOB data).
private void	beginDss(int dssType, boolean ensureLen) Write DSS header DSS Header format is 2 bytes - length 1 byte - 'D0' - indicates DDM data 1 byte - DSS format \|---\|---------\|----------\| \| 0 \| flags \| type \| \|---\|---------\|----------\| \| 0 \| 1 2 3 \| 4 5 6 7 \| \|---\|---------\|----------\| bit 0 - '0' bit 1 - '0' - unchained, '1' - chained bit 2 - '0' - do not continue on error, '1' - continue on error bit 3 - '0' - next DSS has different correlator, '1' - next DSS has same correlator type - 1 - Request DSS - 2 - Reply DSS - 3 - Object DSS - 4 - Communications DSS - 5 - Request DSS where no reply is expected
private int	Returns: minimum number of extended length bytes needed. 0 indicates no extended length needed. calculateExtendedLengthByteCount(long - size of DDM command ddmSize) Calculate extended length byte count which follows the DSS header for extended DDM.
protected void	clearBuffer() Clear the entire send buffer
protected void	clearDdm() Erase all writes for the current ddm and reset the top
protected void	clearDSSesBackToMark(int mark) Does a logical "clear" of everything written to the buffer after the received mark.
protected byte[]	copyDSSDataToEnd(int start) Copy Data to End Create a buffer and copy from the position given to the end of data Note that the position given is treated as relative to the current DSS, for there may be other DSS blocks (chained, presumably) which are sitting unwritten in the buffer.
protected void	createDssObject() Create DSS data object
protected void	createDssReply() Create DSS reply object
protected void	createDssRequest() Create DSS request object NOTE: This is _ONLY_ used for testing the protocol (via the ProtocolTestAdapter.java file in this package)!
protected boolean	doesRequestContainData()
protected void	endDdm() End the current DDM
protected void	endDdmAndDss() End final DDM and DSS header by writing the length in the length location
protected void	endDss(byte chainByte) End DSS header by writing the length in the length location and setting the chain bit.
protected void	endDss() End DSS header by writing the length in the length location and setting the chain bit.
private void	endDss(boolean finalizeLength) End DSS header by writing the length in the length location and setting the chain bit.
private void	ensureLength(int space required length) Ensure that there is space in the buffer
protected void	finalizeChain(byte currChainByte, OutputStream Output stream to which we're flushing. socketOutputStream) Finalize the current DSS chain and send it if needed.
private void	finalizeDssLength() Finish a DSS Layer A object.
protected void	flush() Flush buffer to outputstream
protected void	flush(OutputStream socketOutputStream) Flush buffer to specified stream
private void	flushScalarStreamSegment(boolean lastSegment, OutputStream out)
protected byte[]	Returns: all bytes from `startPos` up to the current position getBufferContents(int the position of the first byte to copy startPos) Get a copy of a subsequence of the output buffer, starting at the specified position and ending at the current buffer position.
protected int	Returns: current position getBufferPosition() Get the current position in the output buffer.
private int	getCorrelationID() Looks at chaining info for previous DSS written, and use that to figure out what the correlation id for the current DSS should be.
protected CcsidManager	getCurrentCcsidManager()
protected int	Returns: current DSS block length getDSSLength() Get the length of the current DSS block we're working on.
private static int	getLayerBStreamingBufferSize()
private static boolean	Returns: `true` if `b` is a continuation byte, or `false` if it is the first byte in a UTF-8 sequence isContinuationByte(byte the byte to check b) Check if a byte value represents a continuation byte in a UTF-8 byte sequence.
private void	markDssAsContinued(boolean forLob) Mark the DSS that we're currently writing as a continued DSS, which is done by setting the high-order bit to "1", per DDM spec.
protected int	markDSSClearPoint() Takes note of the location of the most recently completed DSS in the buffer, and then returns the current offset.
private int	Returns: an upper limit for the number of bytes needed to encode the string maxEncodedLength(String the string to encode s) Find the maximum number of bytes needed to represent the string in the default encoding.
private void	overrideChainByte(int the position on which the chaining byte is located pos, byte the chaining byte that overrides the default chainByte) Override the default chaining byte with the chaining byte that is passed in.
protected void	padBytes(byte value to be written val, int length to be written length) Write pad bytes using spaceChar
private static int	peekStream(InputStream in)
private static OutputStream	placeLayerBStreamingBuffer(OutputStream original)
private int	prepScalarStream(boolean chainedWithSameCorrelator, int codePoint, boolean writeNullByte) prepScalarStream does the following prep for writing stream data: 1.
protected void	reset(DssTrace dssTrace) reset values for sending next message
protected void	resetChainState() Reset any chaining state that needs to be reset at time of the send
private void	sendBytes(OutputStream socketOutputStream)
private void	sendBytes(OutputStream socketOutputStream, boolean flashStream)
protected void	setBufferPosition(int new position position) Change the current position in the output buffer.
protected void	setCMDProtocol() set protocol to CMD protocol
protected void	setEbcdicCcsid()
protected void	setUtf8Ccsid()
protected void	startDdm(int codePoint) Mark the location of the length bytes for the collection so they can be updated later
protected void	truncateDSS(int DSS length value) Truncate the current DSS.
pack-priv void	writeBigDecimal(BigDecimal BigDecimal to write b, int Precision of decimal or numeric type precision, int declared scale scale) Write a Java `java.math.BigDecimal` to packed decimal bytes.
protected void	writeBoolean(boolean value to be written v) Write platform boolean
protected void	writeByte(int byte to be written value) Write byte
protected void	writeBytes(byte[] byte array to be written buf, int - length to write length) Write byte array
protected void	writeBytes(byte[] byte array to be written buf, int - starting position start, int - length to write length) Write byte array
protected void	writeBytes(byte[] byte array to be written buf) Write byte array
pack-priv void	writeCodePoint4Bytes(int - code point to write codePoint, int - value to write after code point value) Write code point and 4 bytes
protected void	writeDouble(double value to be written v) Write platform double
protected void	writeExtendedLength(long size)
protected void	writeFloat(float value to be written v) Write platform float
protected void	writeInt(int value to be written v) Write platform int
protected void	writeLDBytes(byte[] buf)
protected void	writeLDBytes(byte[] buf, int index)
protected void	writeLDString(String value to be written with integer s) Write length delimited string
protected void	writeLDString(String value to be written with integer s, int column index to put in warning index, DRDAStatement the executing statement (null if not invoked as part of statement execution) stmt, boolean true if the value written is for an output parameter in a procedure call isParameter) Write length delimited string
pack-priv void	writeLengthCodePoint(int length, int codePoint)
protected void	writeLong(long value to be written v) Write platform long
protected void	writeNetworkInt(int value to be written value) Write network int
protected void	writeNetworkShort(int value to be written value) Write network short
pack-priv void	writeScalar1Byte(int - code point to write codePoint, int - value to write after code point value) Write scalar 1 byte object includes length, codepoint and value
protected void	writeScalar2Bytes(int - code point to write codePoint, int - value to write after code point value) Write scalar 2 byte object includes length, codepoint and value
protected void	writeScalar2Bytes(int value)
protected void	writeScalarBytes(int - code point to write codePoint, byte[] - byte array to be written buf) Write scalar byte array object includes length, codepoint and value
protected void	writeScalarHeader(int - code point to write codePoint, int - length of object data dataLength) Write scalar object header includes length and codepoint
protected void	writeScalarPaddedBytes(int - code point to write codePoint, byte[] - byte array to be written buf, int - length to pad string to paddedLength, byte - byte to be used for padding padByte) Write padded scalar byte array object includes length, codepoint and value
protected void	writeScalarPaddedBytes(byte[] - byte array to be written buf, int - length to pad string to paddedLength, byte - byte to be used for padding padByte) Write padded scalar byte array object value
pack-priv void	writeScalarPaddedString(int - code point to write codePoint, String - string to be written string, int - length to pad string to paddedLength) Write padded scalar string object includes length, codepoint and value the string is converted into the appropriate codeset (EBCDIC)
protected void	writeScalarPaddedString(DRDAString string to be written drdaString, int length to pad string to paddedLength) Write padded scalar `DRDAString` object value.
protected void	writeScalarStream(boolean chainedWithSameCorrelator, int codePoint, EXTDTAInputStream in, boolean writeNullByte)
pack-priv void	writeScalarString(int - code point to write codePoint, String - string to be written string) Write scalar string object includes length, codepoint and value the string is converted into the appropriate codeset (EBCDIC)
protected void	writeShort(int value to be written v) Write platform short
protected void	writeShort(boolean boolean value true = 1 false = 0 b) Write boolean as short
protected void	writeString(String value to be written s) Write string with default encoding
protected void	writeUDT(Object object to be written val, int index) Write a value of a user defined type.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

agent	back to summary
private DRDAConnThread agent

buffer	back to summary
private ByteBuffer buffer Output buffer.

ccsidManager	back to summary
private CcsidManager ccsidManager

correlationID	back to summary
private int correlationID

DEFAULT_BUFFER_SIZE	back to summary
private static final int DEFAULT_BUFFER_SIZE

dssLengthLocation	back to summary
private int dssLengthLocation

dssTrace	back to summary
private DssTrace dssTrace

ebcdicCcsidManager	back to summary
private EbcdicCcsidManager ebcdicCcsidManager

encoder	back to summary
private final CharsetEncoder encoder Encoder which encodes strings with the server's default encoding.

isContinuationDss	back to summary
private boolean isContinuationDss

isDRDAProtocol	back to summary
private boolean isDRDAProtocol

lastDSSBeforeMark	back to summary
private int lastDSSBeforeMark

markStack	back to summary
private int[] markStack

MAX_MARKS_NESTING	back to summary
private static final int MAX_MARKS_NESTING

MAX_VARCHAR_BYTE_LENGTH	back to summary
pack-priv static final int MAX_VARCHAR_BYTE_LENGTH The maximum length in bytes for strings sent by `writeLDString()`, which is the maximum unsigned integer value that fits in two bytes.

nextCorrelationID	back to summary
private int nextCorrelationID

prevHdrLocation	back to summary
private int prevHdrLocation

previousChainByte	back to summary
private byte previousChainByte

previousCorrId	back to summary
private int previousCorrId

top	back to summary
private int top

totalByteCount	back to summary
pack-priv volatile long totalByteCount

utf8CcsidManager	back to summary
private Utf8CcsidManager utf8CcsidManager

DDMWriter	back to summary
pack-priv DDMWriter(DRDAConnThread agent, DssTrace dssTrace)

Method Detail

beginDss	back to summary
private void beginDss(boolean chainedToNextStructure, int dssType) Begins a DSS stream (for writing LOB data).

beginDss	back to summary
private void beginDss(int dssType, boolean ensureLen) Write DSS header DSS Header format is 2 bytes - length 1 byte - 'D0' - indicates DDM data 1 byte - DSS format \|---\|---------\|----------\| \| 0 \| flags \| type \| \|---\|---------\|----------\| \| 0 \| 1 2 3 \| 4 5 6 7 \| \|---\|---------\|----------\| bit 0 - '0' bit 1 - '0' - unchained, '1' - chained bit 2 - '0' - do not continue on error, '1' - continue on error bit 3 - '0' - next DSS has different correlator, '1' - next DSS has same correlator type - 1 - Request DSS - 2 - Reply DSS - 3 - Object DSS - 4 - Communications DSS - 5 - Request DSS where no reply is expected

beginDss

back to summary

private void beginDss(int dssType, boolean ensureLen)

Write DSS header DSS Header format is 2 bytes - length 1 byte - 'D0' - indicates DDM data 1 byte - DSS format |---|---------|----------| | 0 | flags | type | |---|---------|----------| | 0 | 1 2 3 | 4 5 6 7 | |---|---------|----------| bit 0 - '0' bit 1 - '0' - unchained, '1' - chained bit 2 - '0' - do not continue on error, '1' - continue on error bit 3 - '0' - next DSS has different correlator, '1' - next DSS has same correlator type - 1 - Request DSS - 2 - Reply DSS - 3 - Object DSS - 4 - Communications DSS - 5 - Request DSS where no reply is expected

calculateExtendedLengthByteCount	back to summary
private int calculateExtendedLengthByteCount(long ddmSize) Calculate extended length byte count which follows the DSS header for extended DDM. Parameters ddmSize:long - size of DDM command Returns:int minimum number of extended length bytes needed. 0 indicates no extended length needed.

calculateExtendedLengthByteCount

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private int calculateExtendedLengthByteCount(long ddmSize)

Calculate extended length byte count which follows the DSS header for extended DDM.

Parameters

ddmSize:long: - size of DDM command

Returns:int

minimum number of extended length bytes needed. 0 indicates no extended length needed.

clearBuffer	back to summary
protected void clearBuffer() Clear the entire send buffer

clearDdm	back to summary
protected void clearDdm() Erase all writes for the current ddm and reset the top

clearDSSesBackToMark	back to summary
protected void clearDSSesBackToMark(int mark) Does a logical "clear" of everything written to the buffer after the received mark. It's assumed that this method will be used in error cases when we've started writing one or more DSSes, but then hit an error and need to back out. After backing out, we'll always need to write _something_ back to the client to indicate an error (typically, we just write an SQLCARD) but what exactly gets written is handled in DRDAConnThread. Here, we just do the necessary prep so that whatever comes next will succeed.

clearDSSesBackToMark

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protected void clearDSSesBackToMark(int mark)

Does a logical "clear" of everything written to the buffer after the received mark. It's assumed that this method will be used in error cases when we've started writing one or more DSSes, but then hit an error and need to back out. After backing out, we'll always need to write _something_ back to the client to indicate an error (typically, we just write an SQLCARD) but what exactly gets written is handled in DRDAConnThread. Here, we just do the necessary prep so that whatever comes next will succeed.

copyDSSDataToEnd	back to summary
protected byte[] copyDSSDataToEnd(int start) Copy Data to End Create a buffer and copy from the position given to the end of data Note that the position given is treated as relative to the current DSS, for there may be other DSS blocks (chained, presumably) which are sitting unwritten in the buffer. The caller doesn't know this, though, and works only with the current DSS. getDSSLength, copyDSSDataToEnd, and truncateDSS work together to provide a sub-protocol for DRDAConnThread to use in its implementation of the LMTBLKPRC protocol. They enable the caller to determine when it has written too much data into the current DSS, to reclaim the extra data that won't fit, and to truncate that extra data once it has been reclaimed and stored elsewhere. Note that this support only works for the current DSS. Earlier, chained DSS blocks cannot be accessed using these methods. For additional background information, the interested reader should investigate bugs DERBY-491 and 492 at: http://issues.apache.org/jira/browse/DERBY-491 and http://issues.apache.org/jira/browse/DERBY-492

copyDSSDataToEnd

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protected byte[] copyDSSDataToEnd(int start)

Copy Data to End Create a buffer and copy from the position given to the end of data Note that the position given is treated as relative to the current DSS, for there may be other DSS blocks (chained, presumably) which are sitting unwritten in the buffer. The caller doesn't know this, though, and works only with the current DSS. getDSSLength, copyDSSDataToEnd, and truncateDSS work together to provide a sub-protocol for DRDAConnThread to use in its implementation of the LMTBLKPRC protocol. They enable the caller to determine when it has written too much data into the current DSS, to reclaim the extra data that won't fit, and to truncate that extra data once it has been reclaimed and stored elsewhere. Note that this support only works for the current DSS. Earlier, chained DSS blocks cannot be accessed using these methods. For additional background information, the interested reader should investigate bugs DERBY-491 and 492 at: http://issues.apache.org/jira/browse/DERBY-491 and http://issues.apache.org/jira/browse/DERBY-492

createDssObject	back to summary
protected void createDssObject() Create DSS data object

createDssReply	back to summary
protected void createDssReply() Create DSS reply object

createDssRequest	back to summary
protected void createDssRequest() Create DSS request object NOTE: This is _ONLY_ used for testing the protocol (via the ProtocolTestAdapter.java file in this package)! We should never create a DSS request in normal DRDA processing (we should only create DSS replies and DSS objects).

doesRequestContainData	back to summary
protected boolean doesRequestContainData()

endDdm	back to summary
protected void endDdm() End the current DDM

endDdmAndDss	back to summary
protected void endDdmAndDss() End final DDM and DSS header by writing the length in the length location

endDss	back to summary
protected void endDss(byte chainByte) End DSS header by writing the length in the length location and setting the chain bit. Unlike the other two endDss methods, this one overrides the default chaining byte (which is set in beginDss) with the chaining byte that is passed in. Note This method is only used in association with createDssRequest, and thus is for TESTING purposes only (via ProtocolTestAdpater.java). No calls should be made to this method in normal DRDA processing (because for normal processing, chaining must be determined automatically based on DSS requests).

endDss

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protected void endDss(byte chainByte)

End DSS header by writing the length in the length location and setting the chain bit. Unlike the other two endDss methods, this one overrides the default chaining byte (which is set in beginDss) with the chaining byte that is passed in.

Note

This method is only used in association with createDssRequest, and thus is for TESTING purposes only (via ProtocolTestAdpater.java). No calls should be made to this method in normal DRDA processing (because for normal processing, chaining must be determined automatically based on DSS requests).

endDss	back to summary
protected void endDss() End DSS header by writing the length in the length location and setting the chain bit.

endDss	back to summary
private void endDss(boolean finalizeLength) End DSS header by writing the length in the length location and setting the chain bit.

ensureLength	back to summary
private void ensureLength(int length) Ensure that there is space in the buffer Parameters length:int space required

ensureLength

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private void ensureLength(int length)

Ensure that there is space in the buffer

Parameters

length:int: space required

finalizeChain	back to summary
protected void finalizeChain(byte currChainByte, OutputStream socketOutputStream) throws DRDAProtocolException Finalize the current DSS chain and send it if needed. Updates the chaining state of the most recently-written- to-buffer DSS to correspond to the most recently-read- from-client request. If that chaining state indicates we've reached the end of a chain, then we go ahead and send the buffer across the wire. Parameters socketOutputStream:OutputStream Output stream to which we're flushing.

finalizeChain

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protected void finalizeChain(byte currChainByte, OutputStream socketOutputStream) throws DRDAProtocolException

Finalize the current DSS chain and send it if needed. Updates the chaining state of the most recently-written- to-buffer DSS to correspond to the most recently-read- from-client request. If that chaining state indicates we've reached the end of a chain, then we go ahead and send the buffer across the wire.

Parameters

socketOutputStream:OutputStream: Output stream to which we're flushing.

finalizeDssLength	back to summary
private void finalizeDssLength() Finish a DSS Layer A object. The length of dss object will be calculated based on the difference between the start of the dss, saved on the beginDss call, and the current offset into the buffer which marks the end of the data. In the event the length requires the use of continuation Dss headers, one for each 32k chunk of data, the data will be shifted and the continuation headers will be inserted with the correct values as needed.

finalizeDssLength

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private void finalizeDssLength()

Finish a DSS Layer A object. The length of dss object will be calculated based on the difference between the start of the dss, saved on the beginDss call, and the current offset into the buffer which marks the end of the data. In the event the length requires the use of continuation Dss headers, one for each 32k chunk of data, the data will be shifted and the continuation headers will be inserted with the correct values as needed.

flush	back to summary
protected void flush() throws IOException Flush buffer to outputstream

flush	back to summary
protected void flush(OutputStream socketOutputStream) throws IOException Flush buffer to specified stream

flushScalarStreamSegment	back to summary
private void flushScalarStreamSegment(boolean lastSegment, OutputStream out) throws DRDAProtocolException

getBufferContents back to summary

getBufferContents	back to summary
protected byte[] getBufferContents(int startPos) Get a copy of a subsequence of the output buffer, starting at the specified position and ending at the current buffer position. Parameters startPos:int the position of the first byte to copy Returns:byte[] all bytes from `startPos` up to the current position

protected byte[] getBufferContents(int startPos)

Get a copy of a subsequence of the output buffer, starting at the specified position and ending at the current buffer position.

Parameters

startPos:int: the position of the first byte to copy

Returns:byte[]

all bytes from startPos up to the current position

getBufferPosition	back to summary
protected int getBufferPosition() Get the current position in the output buffer. Returns:int current position

getBufferPosition

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protected int getBufferPosition()

Get the current position in the output buffer.

Returns:int: current position

getCorrelationID	back to summary
private int getCorrelationID() Looks at chaining info for previous DSS written, and use that to figure out what the correlation id for the current DSS should be. Return that correlation id.

getCurrentCcsidManager	back to summary
protected CcsidManager getCurrentCcsidManager()

getDSSLength

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protected int getDSSLength()

Get the length of the current DSS block we're working on. This is used by the LMTBLKPRC protocol, which does its own conversational blocking protocol above the layer of the DRDA blocking. The LMTBLKPRC implementation (in DRDAConnThread) needs to be able to truncate a DSS block when splitting a QRYDTA response.

Returns:int: current DSS block length

getLayerBStreamingBufferSize	back to summary
private static int getLayerBStreamingBufferSize()

isContinuationByte back to summary

private static boolean isContinuationByte(byte b)

Check if a byte value represents a continuation byte in a UTF-8 byte sequence. Continuation bytes in UTF-8 always match the bit pattern 10xxxxxx.

Parameters

b:byte: the byte to check

Returns:boolean

true if b is a continuation byte, or false if it is the first byte in a UTF-8 sequence

markDssAsContinued

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private void markDssAsContinued(boolean forLob)

Mark the DSS that we're currently writing as a continued DSS, which is done by setting the high-order bit to "1", per DDM spec. This means: 1. One or more continuation DSSes will immediately follow the current (continued) DSS. 2. All continuation DSSes will have a 2-byte continuation header, followed by data; in other words, chaining state, correlation id, dss format info, and code point will NOT be included. All of that info is present ONLY in the FIRST DSS in the list of continued DSSes.

Note

A DSS can be a "continuation" DSS _and_ a "continued" DSS at the same time. However, the FIRST DSS to be continued canNOT be a continuation DSS.

markDSSClearPoint	back to summary
protected int markDSSClearPoint() Takes note of the location of the most recently completed DSS in the buffer, and then returns the current offset. This method is used in conjunction with "clearDSSesBackToMark" to allow for DRDAConnThread to "back-out" DSSes in the event of errors.

maxEncodedLength

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private int maxEncodedLength(String s)

Find the maximum number of bytes needed to represent the string in the default encoding.

Parameters

s:String: the string to encode

Returns:int

an upper limit for the number of bytes needed to encode the string

overrideChainByte

back to summary

private void overrideChainByte(int pos, byte chainByte)

Override the default chaining byte with the chaining byte that is passed in.

Parameters

pos:int: the position on which the chaining byte is located
chainByte:byte: the chaining byte that overrides the default

padBytes

back to summary

protected void padBytes(byte val, int length)

Write pad bytes using spaceChar

Parameters

val:byte: value to be written
length:int: length to be written

peekStream	back to summary
private static int peekStream(InputStream in) throws IOException

placeLayerBStreamingBuffer	back to summary
private static OutputStream placeLayerBStreamingBuffer(OutputStream original)

prepScalarStream

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private int prepScalarStream(boolean chainedWithSameCorrelator, int codePoint, boolean writeNullByte) throws DRDAProtocolException

prepScalarStream does the following prep for writing stream data: 1. Flushes an existing DSS segment, if necessary 2. Determines if extended length bytes are needed 3. Creates a new DSS/DDM header and a null byte indicator, if applicable If value of length was less than 0, this method processes streaming as Layer B Streaming. cf. page 315 of specification of DRDA, Version 3, Volume 3

reset	back to summary
protected void reset(DssTrace dssTrace) reset values for sending next message

resetChainState	back to summary
protected void resetChainState() Reset any chaining state that needs to be reset at time of the send

sendBytes	back to summary
private void sendBytes(OutputStream socketOutputStream) throws IOException

sendBytes	back to summary
private void sendBytes(OutputStream socketOutputStream, boolean flashStream) throws IOException

setBufferPosition

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protected void setBufferPosition(int position)

Change the current position in the output buffer.

Parameters

position:int: new position

setCMDProtocol	back to summary
protected void setCMDProtocol() set protocol to CMD protocol

setEbcdicCcsid	back to summary
protected void setEbcdicCcsid()

setUtf8Ccsid	back to summary
protected void setUtf8Ccsid()

startDdm	back to summary
protected void startDdm(int codePoint) Mark the location of the length bytes for the collection so they can be updated later

truncateDSS

back to summary

protected void truncateDSS(int value)

Truncate the current DSS. Before making this call, you should ensure that you have copied the data to be truncated somewhere else, by calling copyDSSDataToEnd

Parameters

value:int: DSS length

writeBigDecimal back to summary

pack-priv void writeBigDecimal(BigDecimal b, int precision, int scale) throws SQLException

Write a Java java.math.BigDecimal to packed decimal bytes.

Parameters

b:BigDecimal: BigDecimal to write
precision:int: Precision of decimal or numeric type
scale:int: declared scale

Exceptions

SQLException:: Thrown if # digits > 31

writeBoolean

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protected void writeBoolean(boolean v)

Write platform boolean

Parameters

v:boolean: value to be written

writeByte

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protected void writeByte(int value)

Write byte

Parameters

value:int: byte to be written

writeBytes

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protected void writeBytes(byte[] buf, int length)

Write byte array

Parameters

buf:byte[]: byte array to be written
length:int: - length to write

writeBytes

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protected void writeBytes(byte[] buf, int start, int length)

Write byte array

Parameters

buf:byte[]: byte array to be written
start:int: - starting position
length:int: - length to write

writeBytes

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protected void writeBytes(byte[] buf)

Write byte array

Parameters

buf:byte[]: byte array to be written

writeCodePoint4Bytes

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pack-priv void writeCodePoint4Bytes(int codePoint, int value)

Write code point and 4 bytes

Parameters

codePoint:int: - code point to write
value:int: - value to write after code point

writeDouble

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protected void writeDouble(double v)

Write platform double

Parameters

v:double: value to be written

writeExtendedLength	back to summary
protected void writeExtendedLength(long size)

writeFloat

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protected void writeFloat(float v)

Write platform float

Parameters

v:float: value to be written

writeInt

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protected void writeInt(int v)

Write platform int

Parameters

v:int: value to be written

writeLDBytes	back to summary
protected void writeLDBytes(byte[] buf)

writeLDBytes	back to summary
protected void writeLDBytes(byte[] buf, int index)

writeLDString

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protected void writeLDString(String s) throws DRDAProtocolException

Write length delimited string

Parameters

s:String: value to be written with integer

writeLDString

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protected void writeLDString(String s, int index, DRDAStatement stmt, boolean isParameter) throws DRDAProtocolException

Write length delimited string

Parameters

s:String: value to be written with integer
index:int: column index to put in warning
stmt:DRDAStatement: the executing statement (null if not invoked as part of statement execution)
isParameter:boolean: true if the value written is for an output parameter in a procedure call

writeLengthCodePoint	back to summary
pack-priv void writeLengthCodePoint(int length, int codePoint)

writeLong

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protected void writeLong(long v)

Write platform long

Parameters

v:long: value to be written

writeNetworkInt

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protected void writeNetworkInt(int value)

Write network int

Parameters

value:int: value to be written

writeNetworkShort

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protected void writeNetworkShort(int value)

Write network short

Parameters

value:int: value to be written

writeScalar1Byte

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pack-priv void writeScalar1Byte(int codePoint, int value)

Write scalar 1 byte object includes length, codepoint and value

Parameters

codePoint:int: - code point to write
value:int: - value to write after code point

writeScalar2Bytes

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protected void writeScalar2Bytes(int codePoint, int value)

Write scalar 2 byte object includes length, codepoint and value

Parameters

codePoint:int: - code point to write
value:int: - value to write after code point

writeScalar2Bytes	back to summary
protected void writeScalar2Bytes(int value)

writeScalarBytes

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protected void writeScalarBytes(int codePoint, byte[] buf)

Write scalar byte array object includes length, codepoint and value

Parameters

codePoint:int: - code point to write
buf:byte[]: - byte array to be written

writeScalarHeader

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protected void writeScalarHeader(int codePoint, int dataLength)

Write scalar object header includes length and codepoint

Parameters

codePoint:int: - code point to write
dataLength:int: - length of object data

writeScalarPaddedBytes

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protected void writeScalarPaddedBytes(int codePoint, byte[] buf, int paddedLength, byte padByte)

Write padded scalar byte array object includes length, codepoint and value

Parameters

codePoint:int: - code point to write
buf:byte[]: - byte array to be written
paddedLength:int: - length to pad string to
padByte:byte: - byte to be used for padding

writeScalarPaddedBytes

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protected void writeScalarPaddedBytes(byte[] buf, int paddedLength, byte padByte)

Write padded scalar byte array object value

Parameters

buf:byte[]: - byte array to be written
paddedLength:int: - length to pad string to
padByte:byte: - byte to be used for padding

writeScalarPaddedString

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pack-priv void writeScalarPaddedString(int codePoint, String string, int paddedLength)

Write padded scalar string object includes length, codepoint and value the string is converted into the appropriate codeset (EBCDIC)

Parameters

codePoint:int: - code point to write
string:String: - string to be written
paddedLength:int: - length to pad string to

writeScalarPaddedString back to summary

protected void writeScalarPaddedString(DRDAString drdaString, int paddedLength)

Write padded scalar DRDAString object value. The string is converted into the appropriate codeset.

Parameters

drdaString:DRDAString: string to be written
paddedLength:int: length to pad string to

writeScalarStream	back to summary
protected void writeScalarStream(boolean chainedWithSameCorrelator, int codePoint, EXTDTAInputStream in, boolean writeNullByte) throws DRDAProtocolException

writeScalarString

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pack-priv void writeScalarString(int codePoint, String string)

Write scalar string object includes length, codepoint and value the string is converted into the appropriate codeset (EBCDIC)

Parameters

codePoint:int: - code point to write
string:String: - string to be written

writeShort

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protected void writeShort(int v)

Write platform short

Parameters

v:int: value to be written

writeShort

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protected void writeShort(boolean b)

Write boolean as short

Parameters

b:boolean: boolean value true = 1 false = 0

writeString

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protected void writeString(String s) throws DRDAProtocolException

Write string with default encoding

Parameters

s:String: value to be written

writeUDT

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protected void writeUDT(Object val, int index) throws DRDAProtocolException

Write a value of a user defined type.

Parameters

val:Object: object to be written

pack-priv Class DDMWriter

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