net.sourceforge.jtds.jdbc
Class ResponseStream

java.lang.Object
  |
  +--net.sourceforge.jtds.jdbc.ResponseStream

public class ResponseStream

extends java.lang.Object

Class to implement an input stream for the server response.

Implementation note:

1. This class contains methods to read different types of data from the server response stream in TDS format.
2. Character translation of String items is carried out.

Version:

$Id: ResponseStream.java,v 1.16 2005/04/04 20:36:56 alin_sinpalean Exp $

Author:

Mike Hutchinson.

Field Summary

private byte[]	buffer The Input packet buffer.
private int	bufferLen The length of current input packet.
private int	bufferPtr The offset of the next byte to read.
private byte[]	byteBuffer A shared byte buffer.
private char[]	charBuffer A shared char buffer.
private boolean	isClosed True if stream is closed.
private SharedSocket	socket The shared network socket.
private int	streamId The unique stream id.

Constructor Summary

(package private)

ResponseStream(SharedSocket socket, int streamId, int bufferSize) Construct a RequestStream object.

Method Summary

(package private) void	close() Close this response stream.
private void	getPacket() Read the next TDS packet from the network.
(package private) int	getServerType() Retrieve the Server type.
(package private) int	getStreamId() Retrieve the unique stream id.
(package private) int	getTdsVersion() Retrieve the TDS version number.
(package private) int	peek() Retrieve the next input byte without reading forward.
(package private) int	read() Retrieve the next input byte from the server response stream.
(package private) int	read(byte[] b) Retrieve a byte array from the server response stream.
(package private) int	read(byte[] b, int off, int len) Retrieve a byte array from the server response stream, specifying a start offset and length.
(package private) int	read(char[] c) Retrieve a char array from the server response stream.
(package private) int	readInt() Retrieve an int value from the server response stream.
(package private) long	readLong() Retrieve a long value from the server response stream.
(package private) java.lang.String	readNonUnicodeString(int len) Retrieve a String object from the server response stream, creating the string from a translated byte array.
(package private) java.lang.String	readNonUnicodeString(int len, CharsetInfo charsetInfo) Retrieve a String object from the server response stream, translating it from a byte array using the specified character set.
(package private) short	readShort() Retrieve a short value from the server response stream.
(package private) java.lang.String	readString(int len) Retrieve a String object from the server response stream.
(package private) java.lang.String	readString(int len, CharsetInfo info) Retrieve a String object from the server response stream, creating the string from a translated byte array.
(package private) java.lang.String	readUnicodeString(int len) Retrieve a UCS2-LE (Unicode) encoded String object from the server response stream.
(package private) int	skip(int skip) Discard bytes from the server response stream.
(package private) void	skipString(int len) Skip a string from the server response stream.
(package private) void	skipToEnd() Consumes the rest of the server response, without parsing it.

Methods inherited from class java.lang.Object

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

Field Detail

socket

private SharedSocket socket

The shared network socket.

buffer

private byte[] buffer

The Input packet buffer.

bufferPtr

private int bufferPtr

The offset of the next byte to read.

bufferLen

private int bufferLen

The length of current input packet.

streamId

private int streamId

The unique stream id.

isClosed

private boolean isClosed

True if stream is closed.

byteBuffer

private byte[] byteBuffer

A shared byte buffer.

charBuffer

private char[] charBuffer

A shared char buffer.

Constructor Detail

ResponseStream

ResponseStream(SharedSocket socket,
               int streamId,
               int bufferSize)

Construct a RequestStream object.

Parameters:

socket - The shared socket object to write to.

streamId - The unique id for this stream (from ResponseStream).

Method Detail

getStreamId

int getStreamId()

Retrieve the unique stream id.

Returns:

the unique stream id as an int.

peek

int peek()
   throws java.io.IOException

Retrieve the next input byte without reading forward.

Returns:

The next byte in the input stream as an int.

Throws:

java.io.IOException -

read

int read()
   throws java.io.IOException

Retrieve the next input byte from the server response stream.

Returns:

The next byte in the input stream as an int.

Throws:

java.io.IOException -

read

int read(byte[] b)
   throws java.io.IOException

Retrieve a byte array from the server response stream.

Parameters:

b - The byte array.

Returns:

The number of bytes read as an int.

Throws:

java.io.IOException -

read

int read(byte[] b,
         int off,
         int len)
   throws java.io.IOException

Retrieve a byte array from the server response stream, specifying a start offset and length.

Parameters:

b - The byte array.

off - The starting offset in the array.

len - The number of bytes to read.

Returns:

The number of bytes read as an int.

Throws:

java.io.IOException -

read

int read(char[] c)
   throws java.io.IOException

Retrieve a char array from the server response stream.

Parameters:

c - The char array.

Returns:

The byte array as a byte[].

Throws:

java.io.IOException -

readString

java.lang.String readString(int len)
                      throws java.io.IOException

Retrieve a String object from the server response stream. If the TDS protocol is 4.2 or 5.0 decode the string using the default server charset, otherwise use UCS2-LE (Unicode).

Parameters:

len - the length of the string to read in bytes in the case of TDS 4.2/5.0 and in characters for TDS 7.0+ (UCS2-LE encoded strings)

Returns:

the result as a String

Throws:

java.io.IOException - if an I/O error occurs

skipString

void skipString(int len)
          throws java.io.IOException

Skip a string from the server response stream. If the TDS protocol is 4.2 or 5.0 len is the length in bytes, otherwise it's the length in UCS2-LE characters (length in bytes == 2 * len).

Parameters:

len - the length of the string to skip in bytes in the case of TDS 4.2/5.0 and in characters for TDS 7.0+ (UCS2-LE encoded strings)

Throws:

java.io.IOException - if an I/O error occurs

readUnicodeString

java.lang.String readUnicodeString(int len)
                             throws java.io.IOException

Retrieve a UCS2-LE (Unicode) encoded String object from the server response stream.

Parameters:

len - the length of the string to read in characters

Returns:

the result as a String

Throws:

java.io.IOException - if an I/O error occurs

readNonUnicodeString

java.lang.String readNonUnicodeString(int len)
                                throws java.io.IOException

Retrieve a String object from the server response stream, creating the string from a translated byte array.

Parameters:

len - the length of the string to read in bytes

Returns:

the result as a String

Throws:

java.io.IOException - if an I/O error occurs

readNonUnicodeString

java.lang.String readNonUnicodeString(int len,
                                      CharsetInfo charsetInfo)
                                throws java.io.IOException

Retrieve a String object from the server response stream, translating it from a byte array using the specified character set.

Parameters:

len - the length of the string to read in bytes

Returns:

the result as a String

Throws:

java.io.IOException - if an I/O error occurs

readString

java.lang.String readString(int len,
                            CharsetInfo info)
                      throws java.io.IOException

Retrieve a String object from the server response stream, creating the string from a translated byte array.

Parameters:

len - the length of the string to read in bytes

info - descriptor of the charset to use

Returns:

the result as a String

Throws:

java.io.IOException - if an I/O error occurs

readShort

short readShort()
          throws java.io.IOException

Retrieve a short value from the server response stream.

Returns:

The result as a short.

Throws:

java.io.IOException -

readInt

int readInt()
      throws java.io.IOException

Retrieve an int value from the server response stream.

Returns:

The result as a int.

Throws:

java.io.IOException -

readLong

long readLong()
        throws java.io.IOException

Retrieve a long value from the server response stream.

Returns:

The result as a long.

Throws:

java.io.IOException -

skip

int skip(int skip)
   throws java.io.IOException

Discard bytes from the server response stream.

Parameters:

skip - The number of bytes to discard.

Returns:

The skip parameter as an int.

skipToEnd

void skipToEnd()

Consumes the rest of the server response, without parsing it.

Note: Use only in extreme cases, packets will not be parsed and could leave the connection in an inconsistent state.

close

void close()

Close this response stream. The stream id is unlinked from the underlying shared socket as well.

getTdsVersion

int getTdsVersion()

Retrieve the TDS version number.

Returns:

The TDS version as an int.

getServerType

int getServerType()

Retrieve the Server type.

Returns:

The Server type as an int.

getPacket

private void getPacket()
                throws java.io.IOException

Read the next TDS packet from the network.

Throws:

java.io.IOException -