public interface GatheringByteChannel extends WritableByteChannel
A gathering write operation writes, in a single invocation, a
sequence of bytes from one or more of a given sequence of buffers.
Gathering writes are often useful when implementing network protocols or
file formats that, for example, group data into segments consisting of one
or more fixed-length headers followed by a variable-length body. Similar
scattering read operations are defined in the ScatteringByteChannel
interface.
Modifier and Type | Method and Description |
---|---|
long |
write(ByteBuffer[] srcs)
Writes a sequence of bytes to this channel from the given buffers.
|
long |
write(ByteBuffer[] srcs,
int offset,
int length)
Writes a sequence of bytes to this channel from a subsequence of the
given buffers.
|
write
long write(ByteBuffer[] srcs, int offset, int length) throws IOException
An attempt is made to write up to r bytes to this channel, where r is the total number of bytes remaining in the specified subsequence of the given buffer array, that is,
at the moment that this method is invoked.srcs[offset].remaining() + srcs[offset+1].remaining() + ... + srcs[offset+length-1].remaining()
Suppose that a byte sequence of length n is written, where 0 <= n <= r. Up to the first srcs[offset].remaining() bytes of this sequence are written from buffer srcs[offset], up to the next srcs[offset+1].remaining() bytes are written from buffer srcs[offset+1], and so forth, until the entire byte sequence is written. As many bytes as possible are written from each buffer, hence the final position of each updated buffer, except the last updated buffer, is guaranteed to be equal to that buffer's limit.
Unless otherwise specified, a write operation will return only after writing all of the r requested bytes. Some types of channels, depending upon their state, may write only some of the bytes or possibly none at all. A socket channel in non-blocking mode, for example, cannot write any more bytes than are free in the socket's output buffer.
This method may be invoked at any time. If another thread has already initiated a write operation upon this channel, however, then an invocation of this method will block until the first operation is complete.
srcs
- The buffers from which bytes are to be retrievedoffset
- The offset within the buffer array of the first buffer from
which bytes are to be retrieved; must be non-negative and no
larger than srcs.lengthlength
- The maximum number of buffers to be accessed; must be
non-negative and no larger than
srcs.length - offsetIndexOutOfBoundsException
- If the preconditions on the offset and length
parameters do not holdNonWritableChannelException
- If this channel was not opened for writingClosedChannelException
- If this channel is closedAsynchronousCloseException
- If another thread closes this channel
while the write operation is in progressClosedByInterruptException
- If another thread interrupts the current thread
while the write operation is in progress, thereby
closing the channel and setting the current thread's
interrupt statusIOException
- If some other I/O error occurslong write(ByteBuffer[] srcs) throws IOException
An invocation of this method of the form c.write(srcs) behaves in exactly the same manner as the invocation
c.write(srcs, 0, srcs.length);
srcs
- The buffers from which bytes are to be retrievedNonWritableChannelException
- If this channel was not opened for writingClosedChannelException
- If this channel is closedAsynchronousCloseException
- If another thread closes this channel
while the write operation is in progressClosedByInterruptException
- If another thread interrupts the current thread
while the write operation is in progress, thereby
closing the channel and setting the current thread's
interrupt statusIOException
- If some other I/O error occurs Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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