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Pipe.SourceChannel.Read Method

Definition

Overloads

Read(ByteBuffer)

Reads a sequence of bytes from this channel into the given buffer.

Read(ByteBuffer[])

Reads a sequence of bytes from this channel into the given buffers.

Read(ByteBuffer[], Int32, Int32)

Reads a sequence of bytes from this channel into a subsequence of the given buffers.

Read(ByteBuffer)

Reads a sequence of bytes from this channel into the given buffer.

[Android.Runtime.Register("read", "(Ljava/nio/ByteBuffer;)I", "GetRead_Ljava_nio_ByteBuffer_Handler")]
public abstract int Read (Java.Nio.ByteBuffer? dst);
[<Android.Runtime.Register("read", "(Ljava/nio/ByteBuffer;)I", "GetRead_Ljava_nio_ByteBuffer_Handler")>]
abstract member Read : Java.Nio.ByteBuffer -> int

Parameters

dst
ByteBuffer

The buffer into which bytes are to be transferred

Returns

The number of bytes read, possibly zero, or -1 if the channel has reached end-of-stream

Implements

Attributes

Remarks

Reads a sequence of bytes from this channel into the given buffer.

An attempt is made to read up to r bytes from the channel, where r is the number of bytes remaining in the buffer, that is, dst.remaining(), at the moment this method is invoked.

Suppose that a byte sequence of length n is read, where 0&nbsp;<=&nbsp;n&nbsp;<=&nbsp;r. This byte sequence will be transferred into the buffer so that the first byte in the sequence is at index p and the last byte is at index p&nbsp;+&nbsp;n&nbsp;-&nbsp;1, where p is the buffer's position at the moment this method is invoked. Upon return the buffer's position will be equal to p&nbsp;+&nbsp;n; its limit will not have changed.

A read operation might not fill the buffer, and in fact it might not read any bytes at all. Whether or not it does so depends upon the nature and state of the channel. A socket channel in non-blocking mode, for example, cannot read any more bytes than are immediately available from the socket's input buffer; similarly, a file channel cannot read any more bytes than remain in the file. It is guaranteed, however, that if a channel is in blocking mode and there is at least one byte remaining in the buffer then this method will block until at least one byte is read.

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.

Java documentation for java.nio.channels.ReadableByteChannel.read(java.nio.ByteBuffer).

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

Read(ByteBuffer[])

Reads a sequence of bytes from this channel into the given buffers.

[Android.Runtime.Register("read", "([Ljava/nio/ByteBuffer;)J", "GetRead_arrayLjava_nio_ByteBuffer_Handler")]
public abstract long Read (Java.Nio.ByteBuffer[]? dsts);
[<Android.Runtime.Register("read", "([Ljava/nio/ByteBuffer;)J", "GetRead_arrayLjava_nio_ByteBuffer_Handler")>]
abstract member Read : Java.Nio.ByteBuffer[] -> int64

Parameters

dsts
ByteBuffer[]

The buffers into which bytes are to be transferred

Returns

The number of bytes read, possibly zero, or -1 if the channel has reached end-of-stream

Implements

Attributes

Remarks

Reads a sequence of bytes from this channel into the given buffers.

An invocation of this method of the form c.read(dsts) behaves in exactly the same manner as the invocation

<blockquote>

c.read(dsts, 0, dsts.length);

</blockquote>

Java documentation for java.nio.channels.ScatteringByteChannel.read(java.nio.ByteBuffer[]).

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

Read(ByteBuffer[], Int32, Int32)

Reads a sequence of bytes from this channel into a subsequence of the given buffers.

[Android.Runtime.Register("read", "([Ljava/nio/ByteBuffer;II)J", "GetRead_arrayLjava_nio_ByteBuffer_IIHandler")]
public abstract long Read (Java.Nio.ByteBuffer[]? dsts, int offset, int length);
[<Android.Runtime.Register("read", "([Ljava/nio/ByteBuffer;II)J", "GetRead_arrayLjava_nio_ByteBuffer_IIHandler")>]
abstract member Read : Java.Nio.ByteBuffer[] * int * int -> int64

Parameters

dsts
ByteBuffer[]

The buffers into which bytes are to be transferred

offset
Int32

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.length

length
Int32

The maximum number of buffers to be accessed; must be non-negative and no larger than dsts.length&nbsp;-&nbsp;offset

Returns

The number of bytes read, possibly zero, or -1 if the channel has reached end-of-stream

Implements

Attributes

Remarks

Reads a sequence of bytes from this channel into a subsequence of the given buffers.

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,

<blockquote>

dsts[offset].remaining()
                + dsts[offset+1].remaining()
                + ... + dsts[offset+length-1].remaining()

</blockquote>

at the moment that this method is invoked.

Suppose that a byte sequence of length n is read, where 0&nbsp;<=&nbsp;n&nbsp;<=&nbsp;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.

Java documentation for java.nio.channels.ScatteringByteChannel.read(java.nio.ByteBuffer[], int, int).

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