Protocol Buffers [Core] 3.7.1 · com.google.protobuf.ByteBufferWriter

Field Summary

Modifier and Type	Field and Description
private static final ThreadLocal<SoftReference<byte[]>>	BUFFER Keeping a soft reference to a thread-local buffer.
private static final float	BUFFER_REALLOCATION_THRESHOLD The fraction of the requested buffer size under which the buffer will be reallocated.
private static final long	CHANNEL_FIELD_OFFSET
private static final Class<?>	FILE_OUTPUT_STREAM_CLASS This is a hack for GAE, where `FileOutputStream` is unavailable.
private static final int	MAX_CACHED_BUFFER_SIZE Maximum size for a cached buffer.
private static final int	MIN_CACHED_BUFFER_SIZE Minimum size for a cached buffer.

Constructor Summary

Access	Constructor and Description
private	ByteBufferWriter()

Method Summary

Modifier and Type	Method and Description
pack-priv static void	clearCachedBuffer() For testing purposes only.
private static byte[]	getBuffer()
private static long	getChannelFieldOffset(Class<?> clazz)
private static byte[]	getOrCreateBuffer(int requestedSize)
private static boolean	needToReallocate(int requestedSize, int bufferLength)
private static Class<?>	safeGetClass(String className)
private static void	setBuffer(byte[] value)
pack-priv static void	write(ByteBuffer buffer, OutputStream output) Writes the remaining content of the buffer to the given stream.
private static boolean	writeToChannel(ByteBuffer buffer, OutputStream output)

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

Field Detail

BUFFER back to summary

BUFFER	back to summary
private static final ThreadLocal<SoftReference<byte[]>> BUFFER Keeping a soft reference to a thread-local buffer. This buffer is used for writing a `ByteBuffer` to an `OutputStream` when no zero-copy alternative was available. Using a "soft" reference since VMs may keep this reference around longer than "weak" (e.g. HotSpot will maintain soft references until memory pressure warrants collection).

private static final ThreadLocal<SoftReference<byte[]>> BUFFER

Keeping a soft reference to a thread-local buffer. This buffer is used for writing a ByteBuffer to an OutputStream when no zero-copy alternative was available. Using a "soft" reference since VMs may keep this reference around longer than "weak" (e.g. HotSpot will maintain soft references until memory pressure warrants collection).

BUFFER_REALLOCATION_THRESHOLD	back to summary
private static final float BUFFER_REALLOCATION_THRESHOLD The fraction of the requested buffer size under which the buffer will be reallocated.

CHANNEL_FIELD_OFFSET	back to summary
private static final long CHANNEL_FIELD_OFFSET

FILE_OUTPUT_STREAM_CLASS	back to summary
private static final Class<?> FILE_OUTPUT_STREAM_CLASS This is a hack for GAE, where `FileOutputStream` is unavailable.

MAX_CACHED_BUFFER_SIZE	back to summary
private static final int MAX_CACHED_BUFFER_SIZE Maximum size for a cached buffer. If a larger buffer is required, it will be allocated but not cached.

MIN_CACHED_BUFFER_SIZE	back to summary
private static final int MIN_CACHED_BUFFER_SIZE Minimum size for a cached buffer. This prevents us from allocating buffers that are too small to be easily reused.

Constructor Detail

ByteBufferWriter	back to summary
private ByteBufferWriter()

Method Detail

clearCachedBuffer	back to summary
pack-priv static void clearCachedBuffer() For testing purposes only. Clears the cached buffer to force a new allocation on the next invocation.

getBuffer	back to summary
private static byte[] getBuffer()

getChannelFieldOffset	back to summary
private static long getChannelFieldOffset(Class<?> clazz)

getOrCreateBuffer	back to summary
private static byte[] getOrCreateBuffer(int requestedSize)

needToReallocate	back to summary
private static boolean needToReallocate(int requestedSize, int bufferLength)

safeGetClass	back to summary
private static Class<?> safeGetClass(String className)

setBuffer	back to summary
private static void setBuffer(byte[] value)

write	back to summary
pack-priv static void write(ByteBuffer buffer, OutputStream output) throws IOException Writes the remaining content of the buffer to the given stream. The buffer `position` will remain unchanged by this method.