public interface ScatteringByteChannel extends ReadableByteChannel
A scattering read operation reads, in a single invocation, a
sequence of bytes into one or more of a given sequence of buffers.
Scattering reads 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
gathering write operations are defined in the GatheringByteChannel interface.
| Modifier and Type | Method and Description |
|---|---|
long |
read(ByteBuffer[] dsts)
Reads a sequence of bytes from this channel into the given buffers.
|
long |
read(ByteBuffer[] dsts,
int offset,
int length)
Reads a sequence of bytes from this channel into a subsequence of the
given buffers.
|
readlong read(ByteBuffer[] dsts, int offset, int length) throws IOException
An invocation of this method attempts to read up to r bytes from this channel, where r is the total number of bytes remaining the specified subsequence of the given buffer array, that is,
dsts[offset].remaining()
+ dsts[offset+1].remaining()
+ ... + dsts[offset+length-1].remaining()Suppose that a byte sequence of length n is read, where 0 <= n <= r. Up to the first dsts[offset].remaining() bytes of this sequence are transferred into buffer dsts[offset], up to the next dsts[offset+1].remaining() bytes are transferred into buffer dsts[offset+1], and so forth, until the entire byte sequence is transferred into the given buffers. As many bytes as possible are transferred into 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.
This method may be invoked at any time. If another thread has already initiated a read operation upon this channel, however, then an invocation of this method will block until the first operation is complete.
dsts - The buffers into which bytes are to be transferredoffset - The offset within the buffer array of the first buffer into
which bytes are to be transferred; must be non-negative and no
larger than dsts.lengthlength - The maximum number of buffers to be accessed; must be
non-negative and no larger than
dsts.length - offsetIndexOutOfBoundsException - If the preconditions on the offset and length
parameters do not holdNonReadableChannelException - If this channel was not opened for readingClosedChannelException - If this channel is closedAsynchronousCloseException - If another thread closes this channel
while the read operation is in progressClosedByInterruptException - If another thread interrupts the current thread
while the read operation is in progress, thereby
closing the channel and setting the current thread's
interrupt statusIOException - If some other I/O error occurslong read(ByteBuffer[] dsts) throws IOException
An invocation of this method of the form c.read(dsts) behaves in exactly the same manner as the invocation
c.read(dsts, 0, dsts.length);
dsts - The buffers into which bytes are to be transferredNonReadableChannelException - If this channel was not opened for readingClosedChannelException - If this channel is closedAsynchronousCloseException - If another thread closes this channel
while the read operation is in progressClosedByInterruptException - If another thread interrupts the current thread
while the read 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.
Copyright © 1993, 2023, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.