Package io.grpc.internal

Class GzipInflatingBuffer

java.lang.Object

io.grpc.internal.GzipInflatingBuffer

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

@NotThreadSafe
class GzipInflatingBuffer
extends java.lang.Object
implements java.io.Closeable

Processes gzip streams, delegating to Inflater to perform on-demand inflation of the deflated blocks. Like GZIPInputStream, this handles concatenated gzip streams. Unlike GZIPInputStream, this allows for incremental processing of gzip streams, allowing data to be inflated as it arrives over the wire.

This also frees the inflate context when the end of a gzip stream is reached without another concatenated stream available to inflate.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private class	GzipInflatingBuffer.GzipMetadataReader	Reads gzip header and trailer bytes from the inflater's buffer (if bytes beyond the inflate block were given to the inflater) and then from gzippedData, and handles updating the CRC and the count of gzipped bytes consumed.
private static class	GzipInflatingBuffer.State

Field Summary

Fields

Modifier and Type	Field	Description
private int	bytesConsumed	Tracks gzipped bytes (including gzip metadata and deflated blocks) consumed during inflateBytes(byte[], int, int) calls.
private boolean	closed
private java.util.zip.CRC32	crc
private int	deflatedBytesConsumed	Tracks deflated bytes (excluding gzip metadata) consumed by the inflater.
private long	expectedGzipTrailerIsize
private static int	GZIP_HEADER_MIN_SIZE
private static int	GZIP_MAGIC
private static int	GZIP_TRAILER_SIZE
private int	gzipHeaderFlag	Extra state variables for parsing gzip header flags.
private GzipInflatingBuffer.GzipMetadataReader	gzipMetadataReader
private CompositeReadableBuffer	gzippedData	This buffer holds all input gzipped data, consisting of blocks of deflated data and the surrounding gzip headers and trailers.
private static int	HEADER_COMMENT_FLAG
private static int	HEADER_CRC_FLAG
private static int	HEADER_EXTRA_FLAG
private static int	HEADER_NAME_FLAG
private int	headerExtraToRead
private static int	INFLATE_BUFFER_SIZE
private java.util.zip.Inflater	inflater
private byte[]	inflaterInput
private int	inflaterInputEnd
private int	inflaterInputStart
private boolean	isStalled
private GzipInflatingBuffer.State	state
private static int	UNSIGNED_SHORT_SIZE

Constructor Summary

Constructors

Constructor	Description
GzipInflatingBuffer()

Method Summary

Modifier and Type	Method	Description
(package private) void	addGzippedBytes(ReadableBuffer buffer)	Adds more gzipped data, which will be consumed only when needed to fulfill requests made via inflateBytes(byte[], int, int).
void	close()
private boolean	fill()
(package private) int	getAndResetBytesConsumed()	Reports bytes consumed by calls to inflateBytes(byte[], int, int) since the last invocation of this method, then resets the count to zero.
(package private) int	getAndResetDeflatedBytesConsumed()	Reports bytes consumed by the inflater since the last invocation of this method, then resets the count to zero.
(package private) boolean	hasPartialData()	Returns true when there is gzippedData that has not been input to the inflater or the inflater has not consumed all of its input, or all data has been consumed but we are at not at the boundary between gzip streams.
private int	inflate(byte[] b, int off, int len)
(package private) int	inflateBytes(byte[] b, int offset, int length)	Attempts to inflate length bytes of data into b.
private boolean	initializeInflater()
(package private) boolean	isStalled()	Returns true when more bytes must be added via addGzippedBytes(io.grpc.internal.ReadableBuffer) to enable additional calls to inflateBytes(byte[], int, int) to make progress.
private boolean	processHeader()
private boolean	processHeaderComment()
private boolean	processHeaderCrc()
private boolean	processHeaderExtra()
private boolean	processHeaderExtraLen()
private boolean	processHeaderName()
private boolean	processTrailer()

Methods inherited from class java.lang.Object

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

Field Detail

INFLATE_BUFFER_SIZE

private static final int INFLATE_BUFFER_SIZE

See Also:

Constant Field Values

UNSIGNED_SHORT_SIZE

private static final int UNSIGNED_SHORT_SIZE

See Also:

Constant Field Values

GZIP_MAGIC

private static final int GZIP_MAGIC

See Also:

Constant Field Values

GZIP_HEADER_MIN_SIZE

private static final int GZIP_HEADER_MIN_SIZE

See Also:

Constant Field Values

GZIP_TRAILER_SIZE

private static final int GZIP_TRAILER_SIZE

See Also:

Constant Field Values

HEADER_CRC_FLAG

private static final int HEADER_CRC_FLAG

See Also:

Constant Field Values

HEADER_EXTRA_FLAG

private static final int HEADER_EXTRA_FLAG

See Also:

Constant Field Values

HEADER_NAME_FLAG

private static final int HEADER_NAME_FLAG

See Also:

Constant Field Values

HEADER_COMMENT_FLAG

private static final int HEADER_COMMENT_FLAG

See Also:

Constant Field Values

gzippedData

private final CompositeReadableBuffer gzippedData

This buffer holds all input gzipped data, consisting of blocks of deflated data and the surrounding gzip headers and trailers. All access to the Gzip headers and trailers must be made via GzipInflatingBuffer.GzipMetadataReader.

crc

private final java.util.zip.CRC32 crc

gzipMetadataReader

private final GzipInflatingBuffer.GzipMetadataReader gzipMetadataReader

inflaterInput

private final byte[] inflaterInput

inflaterInputStart

private int inflaterInputStart

inflaterInputEnd

private int inflaterInputEnd

inflater

private java.util.zip.Inflater inflater

state

private GzipInflatingBuffer.State state

closed

private boolean closed

gzipHeaderFlag

private int gzipHeaderFlag

Extra state variables for parsing gzip header flags.

headerExtraToRead

private int headerExtraToRead

expectedGzipTrailerIsize

private long expectedGzipTrailerIsize

bytesConsumed

private int bytesConsumed

Tracks gzipped bytes (including gzip metadata and deflated blocks) consumed during inflateBytes(byte[], int, int) calls.

deflatedBytesConsumed

private int deflatedBytesConsumed

Tracks deflated bytes (excluding gzip metadata) consumed by the inflater.

isStalled

private boolean isStalled

Constructor Detail

GzipInflatingBuffer

GzipInflatingBuffer()

Method Detail

isStalled

boolean isStalled()

Returns true when more bytes must be added via addGzippedBytes(io.grpc.internal.ReadableBuffer) to enable additional calls to inflateBytes(byte[], int, int) to make progress.

hasPartialData

boolean hasPartialData()

Returns true when there is gzippedData that has not been input to the inflater or the inflater has not consumed all of its input, or all data has been consumed but we are at not at the boundary between gzip streams.

addGzippedBytes

void addGzippedBytes(ReadableBuffer buffer)

Adds more gzipped data, which will be consumed only when needed to fulfill requests made via inflateBytes(byte[], int, int).

close

public void close()

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.io.Closeable

getAndResetBytesConsumed

int getAndResetBytesConsumed()

Reports bytes consumed by calls to inflateBytes(byte[], int, int) since the last invocation of this method, then resets the count to zero.

getAndResetDeflatedBytesConsumed

int getAndResetDeflatedBytesConsumed()

Reports bytes consumed by the inflater since the last invocation of this method, then resets the count to zero.

inflateBytes

int inflateBytes(byte[] b,
                 int offset,
                 int length)
          throws java.util.zip.DataFormatException,
                 java.util.zip.ZipException

Attempts to inflate length bytes of data into b.

Any gzipped bytes consumed by this method will be added to the counter returned by getAndResetBytesConsumed(). This method may consume gzipped bytes without writing any data to b, and may also write data to b without consuming additional gzipped bytes (if the inflater on an earlier call consumed the bytes necessary to produce output).

Parameters:

b - the destination array to receive the bytes.

offset - the starting offset in the destination array.

length - the number of bytes to be copied.

Throws:

java.lang.IndexOutOfBoundsException - if b is too small to hold the requested bytes.

java.util.zip.DataFormatException

java.util.zip.ZipException

processHeader

private boolean processHeader()
                       throws java.util.zip.ZipException

Throws:

java.util.zip.ZipException

processHeaderExtraLen

private boolean processHeaderExtraLen()

processHeaderExtra

private boolean processHeaderExtra()

processHeaderName

private boolean processHeaderName()

processHeaderComment

private boolean processHeaderComment()

processHeaderCrc

private boolean processHeaderCrc()
                          throws java.util.zip.ZipException

Throws:

java.util.zip.ZipException

initializeInflater

private boolean initializeInflater()

inflate

private int inflate(byte[] b,
                    int off,
                    int len)
             throws java.util.zip.DataFormatException,
                    java.util.zip.ZipException

Throws:

java.util.zip.DataFormatException

java.util.zip.ZipException

fill

private boolean fill()

processTrailer

private boolean processTrailer()
                        throws java.util.zip.ZipException

Throws:

java.util.zip.ZipException