Class CompressOutputStream
- All Implemented Interfaces:
Closeable
,Flushable
,AutoCloseable
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Field Summary
FieldsModifier and TypeFieldDescriptionprivate byte[]
private static final int
private static final int
private int
private static final int
private static final int
private final OutputStream
private int
private final MutableInt
private static final int
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Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionvoid
close()
Closes this output stream and releases any system resources associated with this stream.void
flush()
Flushes this output stream and forces any buffered output bytes to be written out.private void
growBuffer
(int len) buf growing use 4 size only to avoid creating/copying that are expensive operations.void
setMaxAllowedPacket
(int maxAllowedPacket) void
write
(byte[] b, int off, int len) Writeslen
bytes from the specified byte array starting at offsetoff
to this output stream.void
write
(int b) Writes the specified byte to this output stream.private void
writeSocket
(boolean end) Methods inherited from class java.io.OutputStream
nullOutputStream, write
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Field Details
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MIN_COMPRESSION_SIZE
private static final int MIN_COMPRESSION_SIZE- See Also:
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SMALL_BUFFER_SIZE
private static final int SMALL_BUFFER_SIZE- See Also:
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MEDIUM_BUFFER_SIZE
private static final int MEDIUM_BUFFER_SIZE- See Also:
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LARGE_BUFFER_SIZE
private static final int LARGE_BUFFER_SIZE- See Also:
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MAX_PACKET_LENGTH
private static final int MAX_PACKET_LENGTH- See Also:
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maxPacketLength
private int maxPacketLength -
out
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sequence
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buf
private byte[] buf -
pos
private int pos
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Constructor Details
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CompressOutputStream
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Method Details
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setMaxAllowedPacket
public void setMaxAllowedPacket(int maxAllowedPacket) -
growBuffer
private void growBuffer(int len) buf growing use 4 size only to avoid creating/copying that are expensive operations. possible size- SMALL_buf_SIZE = 8k (default)
- MEDIUM_buf_SIZE = 128k
- LARGE_buf_SIZE = 1M
- getMaxPacketLength = 16M (+ 4 if using no compression)
- Parameters:
len
- length to add
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write
Writeslen
bytes from the specified byte array starting at offsetoff
to this output stream. The general contract forwrite(b, off, len)
is that some bytes in the arrayb
are written to the output stream in order; elementb[off]
is the first byte written andb[off+len-1]
is the last byte written by this operation.The
write
method ofOutputStream
calls the write method of one argument on each of the bytes to be written out. Subclasses are encouraged to override this method and provide a more efficient implementation.If
b
isnull
, aNullPointerException
is thrown.If
off
is negative, orlen
is negative, oroff+len
is greater than the length of the arrayb
, then an IndexOutOfBoundsException is thrown.- Overrides:
write
in classOutputStream
- Parameters:
b
- the data.off
- the start offset in the data.len
- the number of bytes to write.- Throws:
IOException
- if an I/O error occurs. In particular, anIOException
is thrown if the output stream is closed.
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writeSocket
- Throws:
IOException
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flush
Flushes this output stream and forces any buffered output bytes to be written out. The general contract offlush
is that calling it is an indication that, if any bytes previously written have been buffered by the implementation of the output stream, such bytes should immediately be written to their intended destination.If the intended destination of this stream is an abstraction provided by the underlying operating system, for example a file, then flushing the stream guarantees only that bytes previously written to the stream are passed to the operating system for writing; it does not guarantee that they are actually written to a physical device such as a disk drive.
The
flush
method ofOutputStream
does nothing.- Specified by:
flush
in interfaceFlushable
- Overrides:
flush
in classOutputStream
- Throws:
IOException
- if an I/O error occurs.
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close
Closes this output stream and releases any system resources associated with this stream. The general contract ofclose
is that it closes the output stream. A closed stream cannot perform output operations and cannot be reopened.The
close
method ofOutputStream
does nothing.- Specified by:
close
in interfaceAutoCloseable
- Specified by:
close
in interfaceCloseable
- Overrides:
close
in classOutputStream
- Throws:
IOException
- if an I/O error occurs.
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write
Writes the specified byte to this output stream. The general contract forwrite
is that one byte is written to the output stream. The byte to be written is the eight low-order bits of the argumentb
. The 24 high-order bits ofb
are ignored.Subclasses of
OutputStream
must provide an implementation for this method.- Specified by:
write
in classOutputStream
- Parameters:
b
- thebyte
.- Throws:
IOException
- if an I/O error occurs. In particular, anIOException
may be thrown if the output stream has been closed.
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