Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary: [Methods](https://developer.android.com/reference/java/nio/channels/WritableByteChannel#pubmethods) \| [Inherited Methods](https://developer.android.com/reference/java/nio/channels/WritableByteChannel#inhmethods)

# WritableByteChannel


`
public


interface
WritableByteChannel
`


`


implements

https://developer.android.com/reference/java/nio/channels/Channel


`

|---|
| java.nio.channels.WritableByteChannel |

|---|
| Known indirect subclasses [ByteChannel](https://developer.android.com/reference/java/nio/channels/ByteChannel), [DatagramChannel](https://developer.android.com/reference/java/nio/channels/DatagramChannel), [FileChannel](https://developer.android.com/reference/java/nio/channels/FileChannel), [GatheringByteChannel](https://developer.android.com/reference/java/nio/channels/GatheringByteChannel), [Pipe.SinkChannel](https://developer.android.com/reference/java/nio/channels/Pipe.SinkChannel), [SeekableByteChannel](https://developer.android.com/reference/java/nio/channels/SeekableByteChannel), [SocketChannel](https://developer.android.com/reference/java/nio/channels/SocketChannel) |---|---| | [ByteChannel](https://developer.android.com/reference/java/nio/channels/ByteChannel) | A channel that can read and write bytes. | | [DatagramChannel](https://developer.android.com/reference/java/nio/channels/DatagramChannel) | A selectable channel for datagram-oriented sockets. | | [FileChannel](https://developer.android.com/reference/java/nio/channels/FileChannel) | A channel for reading, writing, mapping, and manipulating a file. | | [GatheringByteChannel](https://developer.android.com/reference/java/nio/channels/GatheringByteChannel) | A channel that can write bytes from a sequence of buffers. | | [Pipe.SinkChannel](https://developer.android.com/reference/java/nio/channels/Pipe.SinkChannel) | A channel representing the writable end of a `https://developer.android.com/reference/java/nio/channels/Pipe`. | | [SeekableByteChannel](https://developer.android.com/reference/java/nio/channels/SeekableByteChannel) | A byte channel that maintains a current *position* and allows the position to be changed. | | [SocketChannel](https://developer.android.com/reference/java/nio/channels/SocketChannel) | A selectable channel for stream-oriented connecting sockets. | |

<br />

*** ** * ** ***

A channel that can write bytes.

Only one write operation upon a writable channel may be in progress at
any given time. If one thread initiates a write operation upon a channel
then any other thread that attempts to initiate another write operation will
block until the first operation is complete. Whether or not other kinds of
I/O operations may proceed concurrently with a write operation depends upon
the type of the channel.

<br />

## Summary

| ### Public methods ||
|---|---|
| ` abstract int` | ` https://developer.android.com/reference/java/nio/channels/WritableByteChannel#write(java.nio.ByteBuffer)(https://developer.android.com/reference/java/nio/ByteBuffer src) ` Writes a sequence of bytes to this channel from the given buffer. |

| ### Inherited methods |
|---|---|
| From interface ` https://developer.android.com/reference/java/nio/channels/Channel ` |---|---| | ` abstract void` | ` https://developer.android.com/reference/java/nio/channels/Channel#close()() ` Closes this channel. | | ` abstract boolean` | ` https://developer.android.com/reference/java/nio/channels/Channel#isOpen()() ` Tells whether or not this channel is open. | ||
| From interface ` https://developer.android.com/reference/java/io/Closeable ` |---|---| | ` abstract void` | ` https://developer.android.com/reference/java/io/Closeable#close()() ` Closes this stream and releases any system resources associated with it. | ||
| From interface ` https://developer.android.com/reference/java/lang/AutoCloseable ` |---|---| | ` abstract void` | ` https://developer.android.com/reference/java/lang/AutoCloseable#close()() ` Closes this resource, relinquishing any underlying resources. | ||

## Public methods

### write

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public abstract int write (ByteBuffer src)
```

Writes a sequence of bytes to this channel from the given buffer.

An attempt is made to write up to *r* bytes to the channel,
where *r* is the number of bytes remaining in the buffer, that is,
`src.remaining()`, at the moment this method is invoked.

Suppose that a byte sequence of length *n* is written, where
`0` `<=` *n* `<=` *r*.
This byte sequence will be transferred from the buffer starting at index
*p*, where *p* is the buffer's position at the moment this
method is invoked; the index of the last byte written will be
*p* `+` *n* `-` `1`.
Upon return the buffer's position will be equal to
*p* `+` *n*; its limit will not have changed.

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.

<br />

<br />

| Parameters ||
|---|---|
| `src` | `ByteBuffer`: The buffer from which bytes are to be retrieved <br /> |

| Returns ||
|---|---|
| `int` | The number of bytes written, possibly zero <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | If some other I/O error occurs |
| `https://developer.android.com/reference/java/nio/channels/AsynchronousCloseException` | If another thread closes this channel while the write operation is in progress |
| `https://developer.android.com/reference/java/nio/channels/ClosedByInterruptException` | 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 status |
| `https://developer.android.com/reference/java/nio/channels/ClosedChannelException` | If this channel is closed |
| `https://developer.android.com/reference/java/nio/channels/NonWritableChannelException` | If this channel was not opened for writing |