io.netty.handler.stream

Class ChunkedFile

java.lang.Object

io.netty.handler.stream.ChunkedFile

All Implemented Interfaces:

ChunkedInput<ByteBuf>

public class ChunkedFile
extends Object
implements ChunkedInput<ByteBuf>

A ChunkedInput that fetches data from a file chunk by chunk.

If your operating system supports zero-copy file transfer such as sendfile(), you might want to use FileRegion instead.

Constructor Summary

Constructors

Constructor and Description
ChunkedFile(File file) Creates a new instance that fetches data from the specified file.
ChunkedFile(File file, int chunkSize) Creates a new instance that fetches data from the specified file.
ChunkedFile(RandomAccessFile file) Creates a new instance that fetches data from the specified file.
ChunkedFile(RandomAccessFile file, int chunkSize) Creates a new instance that fetches data from the specified file.
ChunkedFile(RandomAccessFile file, long offset, long length, int chunkSize) Creates a new instance that fetches data from the specified file.

Method Summary

Modifier and Type	Method and Description
void	close() Releases the resources associated with the input.
long	currentOffset() Returns the offset in the file where the transfer is happening currently.
long	endOffset() Returns the offset in the file where the transfer will end.
boolean	isEndOfInput() Return true if and only if there is no data left in the stream and the stream has reached at its end.
long	length() Returns the length of the input.
long	progress() Returns current transfer progress.
ByteBuf	readChunk(ByteBufAllocator allocator) Fetches a chunked data from the stream.
ByteBuf	readChunk(ChannelHandlerContext ctx) Deprecated.
long	startOffset() Returns the offset in the file where the transfer began.

Methods inherited from class java.lang.Object

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

Constructor Detail

ChunkedFile

public ChunkedFile(File file)
            throws IOException

Creates a new instance that fetches data from the specified file.

Throws:

IOException

ChunkedFile

public ChunkedFile(File file,
                   int chunkSize)
            throws IOException

Creates a new instance that fetches data from the specified file.

Parameters:

chunkSize - the number of bytes to fetch on each readChunk(ChannelHandlerContext) call

Throws:

IOException

ChunkedFile

public ChunkedFile(RandomAccessFile file)
            throws IOException

Creates a new instance that fetches data from the specified file.

Throws:

IOException

ChunkedFile

public ChunkedFile(RandomAccessFile file,
                   int chunkSize)
            throws IOException

Creates a new instance that fetches data from the specified file.

Parameters:

chunkSize - the number of bytes to fetch on each readChunk(ChannelHandlerContext) call

Throws:

IOException

ChunkedFile

public ChunkedFile(RandomAccessFile file,
                   long offset,
                   long length,
                   int chunkSize)
            throws IOException

Creates a new instance that fetches data from the specified file.

Parameters:

offset - the offset of the file where the transfer begins

length - the number of bytes to transfer

chunkSize - the number of bytes to fetch on each readChunk(ChannelHandlerContext) call

Throws:

IOException

Method Detail

startOffset

public long startOffset()

Returns the offset in the file where the transfer began.

endOffset

public long endOffset()

Returns the offset in the file where the transfer will end.

currentOffset

public long currentOffset()

Returns the offset in the file where the transfer is happening currently.

isEndOfInput

public boolean isEndOfInput()
                     throws Exception

Description copied from interface: ChunkedInput

Return true if and only if there is no data left in the stream and the stream has reached at its end.

Specified by:

isEndOfInput in interface ChunkedInput<ByteBuf>

Throws:

Exception

close

public void close()
           throws Exception

Description copied from interface: ChunkedInput

Releases the resources associated with the input.

Specified by:

close in interface ChunkedInput<ByteBuf>

Throws:

Exception

readChunk

@Deprecated
public ByteBuf readChunk(ChannelHandlerContext ctx)
                              throws Exception

Deprecated.

Specified by:

readChunk in interface ChunkedInput<ByteBuf>

Parameters:

ctx - The context which provides a ByteBufAllocator if buffer allocation is necessary.

Returns:

the fetched chunk. null if there is no data left in the stream. Please note that null does not necessarily mean that the stream has reached at its end. In a slow stream, the next chunk might be unavailable just momentarily.

Throws:

Exception

readChunk

public ByteBuf readChunk(ByteBufAllocator allocator)
                  throws Exception

Description copied from interface: ChunkedInput

Fetches a chunked data from the stream. Once this method returns the last chunk and thus the stream has reached at its end, any subsequent ChunkedInput.isEndOfInput() call must return true.

Specified by:

readChunk in interface ChunkedInput<ByteBuf>

Parameters:

allocator - ByteBufAllocator if buffer allocation is necessary.

Returns:

the fetched chunk. null if there is no data left in the stream. Please note that null does not necessarily mean that the stream has reached at its end. In a slow stream, the next chunk might be unavailable just momentarily.

Throws:

Exception

length

public long length()

Description copied from interface: ChunkedInput

Returns the length of the input.

Specified by:

length in interface ChunkedInput<ByteBuf>

Returns:

the length of the input if the length of the input is known. a negative value if the length of the input is unknown.

progress

public long progress()

Description copied from interface: ChunkedInput

Returns current transfer progress.

Specified by:

progress in interface ChunkedInput<ByteBuf>