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FileChannel.TransferTo(Int64, Int64, IWritableByteChannel) Method

Definition

Transfers bytes from this channel's file to the given writable byte channel.

[Android.Runtime.Register("transferTo", "(JJLjava/nio/channels/WritableByteChannel;)J", "GetTransferTo_JJLjava_nio_channels_WritableByteChannel_Handler")]
public abstract long TransferTo (long position, long count, Java.Nio.Channels.IWritableByteChannel? target);
[<Android.Runtime.Register("transferTo", "(JJLjava/nio/channels/WritableByteChannel;)J", "GetTransferTo_JJLjava_nio_channels_WritableByteChannel_Handler")>]
abstract member TransferTo : int64 * int64 * Java.Nio.Channels.IWritableByteChannel -> int64

Parameters

position
Int64

The position within the file at which the transfer is to begin; must be non-negative

count
Int64

The maximum number of bytes to be transferred; must be non-negative

target
IWritableByteChannel

The target channel

Returns

The number of bytes, possibly zero, that were actually transferred

Attributes

Exceptions

if the parameters are invalid.

if this channel is not readable.

if the target channel is not writable.

if either channel has already been closed.

if either channel is closed by other threads during this operation.

if the thread is interrupted during this operation.

if any I/O error occurs.

Remarks

Transfers bytes from this channel's file to the given writable byte channel.

An attempt is made to read up to count bytes starting at the given position in this channel's file and write them to the target channel. An invocation of this method may or may not transfer all of the requested bytes; whether or not it does so depends upon the natures and states of the channels. Fewer than the requested number of bytes are transferred if this channel's file contains fewer than count bytes starting at the given position, or if the target channel is non-blocking and it has fewer than count bytes free in its output buffer.

This method does not modify this channel's position. If the given position is greater than the file's current size then no bytes are transferred. If the target channel has a position then bytes are written starting at that position and then the position is incremented by the number of bytes written.

This method is potentially much more efficient than a simple loop that reads from this channel and writes to the target channel. Many operating systems can transfer bytes directly from the filesystem cache to the target channel without actually copying them.

Java documentation for java.nio.channels.FileChannel.transferTo(long, long, java.nio.channels.WritableByteChannel).

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to