MySQL Connector/J 9.2.0 · com.mysql.cj.protocol.a.CompressedInputStream

Modifier and Type	Field and Description
private byte[]	buffer The packet data after it has been un-compressed
private InputStream	in The stream we are reading from the server
private Inflater	inflater The ZIP inflater used to un-compress packets
private Log	log Connection logger
private byte[]	packetHeaderBuffer The buffer to read packet headers into
private int	pos The position we are reading from
private RuntimeProperty<Boolean>	traceProtocol Connection property reference

Access	Constructor and Description
public	CompressedInputStream(InputStream original server InputStream streamFromServer, RuntimeProperty<Boolean> "traceProtocol" property traceProtocol, Log logger log) Creates a new CompressedInputStream that reads the given stream from the server.

Method Summary

Modifier and Type	Method and Description
public int	available() Overrides java.io.InputStream.available. Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking, which may be 0, or 0 when end of stream is detected.
public void	close() Overrides java.io.InputStream.close. Implements java.io.Closeable.close. Closes this input stream and releases any system resources associated with the stream.
private void	getNextPacketFromServer() Retrieves and un-compressed (if necessary) the next packet from the server.
private void	getNextPacketIfRequired(int the number of bytes to be read numBytes) Determines if another packet needs to be read from the server to be able to read numBytes from the stream.
public int	read() Implements abstract java.io.InputStream.read. Reads the next byte of data from the input stream.
public int	read(byte[] the buffer into which the data is read. b) Overrides java.io.InputStream.read. Reads some number of bytes from the input stream and stores them into the buffer array `b`.
public int	read(byte[] the buffer into which the data is read. b, int the start offset in array `b` at which the data is written. off, int the maximum number of bytes to read. len) Overrides java.io.InputStream.read. Reads up to `len` bytes of data from the input stream into an array of bytes.
private final int	readFully(byte[] b, int off, int len)
public long	skip(long the number of bytes to be skipped. n) Overrides java.io.InputStream.skip. Skips over and discards `n` bytes of data from this input stream.

Inherited from java.io.InputStream:: mark markSupported nullInputStream readAllBytes readNBytes readNBytes reset skipNBytes transferTo

buffer	back to summary
private byte[] buffer The packet data after it has been un-compressed

in	back to summary
private InputStream in The stream we are reading from the server

inflater	back to summary
private Inflater inflater The ZIP inflater used to un-compress packets

log	back to summary
private Log log Connection logger

packetHeaderBuffer	back to summary
private byte[] packetHeaderBuffer The buffer to read packet headers into

pos	back to summary
private int pos The position we are reading from

traceProtocol	back to summary
private RuntimeProperty<Boolean> traceProtocol Connection property reference

CompressedInputStream	back to summary
public CompressedInputStream(InputStream streamFromServer, RuntimeProperty<Boolean> traceProtocol, Log log) Creates a new CompressedInputStream that reads the given stream from the server. Parameters streamFromServer:InputStream original server InputStream traceProtocol:RuntimeProperty<Boolean> "traceProtocol" property log:Log logger

Method Detail

available back to summary

available	back to summary
public int available() throws IOException Overrides java.io.InputStream.available. Doc from java.io.InputStream.available. Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking, which may be 0, or 0 when end of stream is detected. The read might be on the same thread or another thread. A single read or skip of this many bytes will not block, but may read or skip fewer bytes. Note that while some implementations of `InputStream` will return the total number of bytes in the stream, many will not. It is never correct to use the return value of this method to allocate a buffer intended to hold all data in this stream. A subclass's implementation of this method may choose to throw an `IOException` if this input stream has been closed by invoking the `close()` method. Returns:int an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking or `0` when it reaches the end of the input stream. Annotations @Override Exceptions IOException: if an I/O error occurs.

public int available() throws IOException

Overrides java.io.InputStream.available.

Doc from java.io.InputStream.available.

Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking, which may be 0, or 0 when end of stream is detected. The read might be on the same thread or another thread. A single read or skip of this many bytes will not block, but may read or skip fewer bytes.

Note that while some implementations of InputStream will return the total number of bytes in the stream, many will not. It is never correct to use the return value of this method to allocate a buffer intended to hold all data in this stream.

A subclass's implementation of this method may choose to throw an IOException if this input stream has been closed by invoking the close() method.

Returns:int

an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking or 0 when it reaches the end of the input stream.

Annotations

@Override

Exceptions

IOException:: if an I/O error occurs.

close	back to summary
public void close() throws IOException Overrides java.io.InputStream.close. Implements java.io.Closeable.close. Doc from java.io.InputStream.close. Closes this input stream and releases any system resources associated with the stream. Annotations @Override Exceptions IOException: if an I/O error occurs.

back to summary

public void close() throws IOException

Overrides java.io.InputStream.close.

Implements java.io.Closeable.close.

Doc from java.io.InputStream.close.

Closes this input stream and releases any system resources associated with the stream.

Annotations

@Override

Exceptions

IOException:: if an I/O error occurs.

getNextPacketFromServer	back to summary
private void getNextPacketFromServer() throws IOException Retrieves and un-compressed (if necessary) the next packet from the server. Exceptions IOException: if an I/O error occurs

getNextPacketFromServer

back to summary

private void getNextPacketFromServer() throws IOException

Retrieves and un-compressed (if necessary) the next packet from the server.

Exceptions

IOException:: if an I/O error occurs

getNextPacketIfRequired	back to summary
private void getNextPacketIfRequired(int numBytes) throws IOException Determines if another packet needs to be read from the server to be able to read numBytes from the stream. Parameters numBytes:int the number of bytes to be read Exceptions IOException: if an I/O error occors.

getNextPacketIfRequired

back to summary

private void getNextPacketIfRequired(int numBytes) throws IOException

Determines if another packet needs to be read from the server to be able to read numBytes from the stream.

Parameters

numBytes:int: the number of bytes to be read

Exceptions

IOException:: if an I/O error occors.

read back to summary

read	back to summary
public int read() throws IOException Implements abstract java.io.InputStream.read. Doc from java.io.InputStream.read. Reads the next byte of data from the input stream. The value byte is returned as an `int` in the range `0` to `255`. If no byte is available because the end of the stream has been reached, the value `-1` is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown. Returns:int the next byte of data, or `-1` if the end of the stream is reached. Annotations @Override Exceptions IOException: if an I/O error occurs.

public int read() throws IOException

Implements abstract java.io.InputStream.read.

Doc from java.io.InputStream.read.

Reads the next byte of data from the input stream. The value byte is returned as an int in the range 0 to 255. If no byte is available because the end of the stream has been reached, the value -1 is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

Returns:int

the next byte of data, or -1 if the end of the stream is reached.

Annotations

@Override

Exceptions

IOException:: if an I/O error occurs.

read back to summary

read	back to summary
public int read(byte[] b) throws IOException Overrides java.io.InputStream.read. Doc from java.io.InputStream.read. Reads some number of bytes from the input stream and stores them into the buffer array `b`. The number of bytes actually read is returned as an integer. This method blocks until input data is available, end of file is detected, or an exception is thrown. If the length of `b` is zero, then no bytes are read and `0` is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at the end of the file, the value `-1` is returned; otherwise, at least one byte is read and stored into `b`. The first byte read is stored into element `b[0]`, the next one into `b[1]`, and so on. The number of bytes read is, at most, equal to the length of `b`. Let k be the number of bytes actually read; these bytes will be stored in elements `b[0]` through `b[`k`-1]`, leaving elements `b[`k`]` through `b[b.length-1]` unaffected. Parameters b:byte[] the buffer into which the data is read. Returns:int the total number of bytes read into the buffer, or `-1` if there is no more data because the end of the stream has been reached. Annotations @Override Exceptions IOException: If the first byte cannot be read for any reason other than the end of the file, if the input stream has been closed, or if some other I/O error occurs.

public int read(byte[] b) throws IOException

Overrides java.io.InputStream.read.

Doc from java.io.InputStream.read.

Reads some number of bytes from the input stream and stores them into the buffer array b. The number of bytes actually read is returned as an integer. This method blocks until input data is available, end of file is detected, or an exception is thrown.

If the length of b is zero, then no bytes are read and 0 is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at the end of the file, the value -1 is returned; otherwise, at least one byte is read and stored into b.

The first byte read is stored into element b[0], the next one into b[1], and so on. The number of bytes read is, at most, equal to the length of b. Let k be the number of bytes actually read; these bytes will be stored in elements b[0] through b[k-1], leaving elements b[k] through b[b.length-1] unaffected.

Parameters

b:byte[]: the buffer into which the data is read.

Returns:int

the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.

Annotations

@Override

Exceptions

IOException:: If the first byte cannot be read for any reason other than the end of the file, if the input stream has been closed, or if some other I/O error occurs.

read back to summary

read	back to summary
public int read(byte[] b, int off, int len) throws IOException Overrides java.io.InputStream.read. Doc from java.io.InputStream.read. Reads up to `len` bytes of data from the input stream into an array of bytes. An attempt is made to read as many as `len` bytes, but a smaller number may be read. The number of bytes actually read is returned as an integer. This method blocks until input data is available, end of file is detected, or an exception is thrown. If `len` is zero, then no bytes are read and `0` is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at end of file, the value `-1` is returned; otherwise, at least one byte is read and stored into `b`. The first byte read is stored into element `b[off]`, the next one into `b[off+1]`, and so on. The number of bytes read is, at most, equal to `len`. Let k be the number of bytes actually read; these bytes will be stored in elements `b[off]` through `b[off+`k`-1]`, leaving elements `b[off+`k`]` through `b[off+len-1]` unaffected. In every case, elements `b[0]` through `b[off-1]` and elements `b[off+len]` through `b[b.length-1]` are unaffected. Parameters b:byte[] the buffer into which the data is read. off:int the start offset in array `b` at which the data is written. len:int the maximum number of bytes to read. Returns:int the total number of bytes read into the buffer, or `-1` if there is no more data because the end of the stream has been reached. Annotations @Override Exceptions IOException: If the first byte cannot be read for any reason other than end of file, or if the input stream has been closed, or if some other I/O error occurs.

public int read(byte[] b, int off, int len) throws IOException

Overrides java.io.InputStream.read.

Doc from java.io.InputStream.read.

Reads up to len bytes of data from the input stream into an array of bytes. An attempt is made to read as many as len bytes, but a smaller number may be read. The number of bytes actually read is returned as an integer.

This method blocks until input data is available, end of file is detected, or an exception is thrown.

If len is zero, then no bytes are read and 0 is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at end of file, the value -1 is returned; otherwise, at least one byte is read and stored into b.

The first byte read is stored into element b[off], the next one into b[off+1], and so on. The number of bytes read is, at most, equal to len. Let k be the number of bytes actually read; these bytes will be stored in elements b[off] through b[off+k-1], leaving elements b[off+k] through b[off+len-1] unaffected.

In every case, elements b[0] through b[off-1] and elements b[off+len] through b[b.length-1] are unaffected.

Parameters

b:byte[]: the buffer into which the data is read.
off:int: the start offset in array b at which the data is written.
len:int: the maximum number of bytes to read.

Returns:int

the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.

Annotations

@Override

Exceptions

IOException:: If the first byte cannot be read for any reason other than end of file, or if the input stream has been closed, or if some other I/O error occurs.

readFully	back to summary
private final int readFully(byte[] b, int off, int len) throws IOException

skip back to summary

skip	back to summary
public long skip(long n) throws IOException Overrides java.io.InputStream.skip. Doc from java.io.InputStream.skip. Skips over and discards `n` bytes of data from this input stream. The `skip` method may, for a variety of reasons, end up skipping over some smaller number of bytes, possibly `0`. This may result from any of a number of conditions; reaching end of file before `n` bytes have been skipped is only one possibility. The actual number of bytes skipped is returned. If `n` is negative, the `skip` method for class `InputStream` always returns 0, and no bytes are skipped. Subclasses may handle the negative value differently. Parameters n:long the number of bytes to be skipped. Returns:long the actual number of bytes skipped which might be zero. Annotations @Override Exceptions IOException: if an I/O error occurs.

public long skip(long n) throws IOException

Overrides java.io.InputStream.skip.

Doc from java.io.InputStream.skip.

Skips over and discards n bytes of data from this input stream. The skip method may, for a variety of reasons, end up skipping over some smaller number of bytes, possibly 0. This may result from any of a number of conditions; reaching end of file before n bytes have been skipped is only one possibility. The actual number of bytes skipped is returned. If n is negative, the skip method for class InputStream always returns 0, and no bytes are skipped. Subclasses may handle the negative value differently.

Parameters

n:long: the number of bytes to be skipped.

Returns:long

the actual number of bytes skipped which might be zero.

Annotations

@Override

Exceptions

IOException:: if an I/O error occurs.

public Class CompressedInputStream

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail