JRuby Base 10.0.0.0 · org.jruby.util.io.SeekableByteChannelImpl

Modifier and Type	Field and Description
private final int	count
private static final Field	countField
private final ByteArrayInputStream	in
private final int	mark
private static final Field	markField
private static final Field	posField
private int	truncatedBy
pack-priv static final boolean	USABLE

Access	Constructor and Description
pack-priv	SeekableByteChannelImpl(ByteArrayInputStream in)

Method Summary

Modifier and Type	Method and Description
private static Field	accessibleField(final String name)
private static int	count(ByteArrayInputStream in)
protected void	implCloseChannel() Implements abstract java.nio.channels.spi.AbstractInterruptibleChannel.implCloseChannel. Closes this channel.
private static int	mark(ByteArrayInputStream in)
private static int	pos(ByteArrayInputStream in)
public long	position() Implements java.nio.channels.SeekableByteChannel.position. Returns this channel's position.
public synchronized SeekableByteChannel	position(long The new position, a non-negative integer counting the number of bytes from the beginning of the entity newPosition) Implements java.nio.channels.SeekableByteChannel.position. Sets this channel's position.
public synchronized int	read(ByteBuffer The buffer into which bytes are to be transferred target) Implements java.nio.channels.ReadableByteChannel.read, java.nio.channels.SeekableByteChannel.read. Reads a sequence of bytes from this channel into the given buffer.
private static int	readIntField(ByteArrayInputStream self, Field field)
public long	size() Implements java.nio.channels.SeekableByteChannel.size. Returns the current size of entity to which this channel is connected.
public SeekableByteChannel	truncate(long The new size, a non-negative byte count size) Implements java.nio.channels.SeekableByteChannel.truncate. Truncates the entity, to which this channel is connected, to the given size.
public int	write(ByteBuffer The buffer from which bytes are to be retrieved src) Implements java.nio.channels.SeekableByteChannel.write. Writes a sequence of bytes to this channel from the given buffer.

Inherited from java.nio.channels.spi.AbstractInterruptibleChannel:: begin close end isOpen

count	back to summary
private final int count

countField	back to summary
private static final Field countField

in	back to summary
private final ByteArrayInputStream in

mark	back to summary
private final int mark

markField	back to summary
private static final Field markField

posField	back to summary
private static final Field posField

truncatedBy	back to summary
private int truncatedBy

USABLE	back to summary
pack-priv static final boolean USABLE

SeekableByteChannelImpl	back to summary
pack-priv SeekableByteChannelImpl(ByteArrayInputStream in)

Method Detail

accessibleField	back to summary
private static Field accessibleField(final String name)

count	back to summary
private static int count(ByteArrayInputStream in)

implCloseChannel back to summary

implCloseChannel	back to summary
protected void implCloseChannel() throws IOException Implements abstract java.nio.channels.spi.AbstractInterruptibleChannel.implCloseChannel. Doc from java.nio.channels.spi.AbstractInterruptibleChannel.implCloseChannel. Closes this channel. This method is invoked by the `close` method in order to perform the actual work of closing the channel. This method is only invoked if the channel has not yet been closed, and it is never invoked more than once. An implementation of this method must arrange for any other thread that is blocked in an I/O operation upon this channel to return immediately, either by throwing an exception or by returning normally. Annotations @Override Exceptions IOException: If an I/O error occurs while closing the channel

protected void implCloseChannel() throws IOException

Implements abstract java.nio.channels.spi.AbstractInterruptibleChannel.implCloseChannel.

Doc from java.nio.channels.spi.AbstractInterruptibleChannel.implCloseChannel.

Closes this channel.

This method is invoked by the close method in order to perform the actual work of closing the channel. This method is only invoked if the channel has not yet been closed, and it is never invoked more than once.

An implementation of this method must arrange for any other thread that is blocked in an I/O operation upon this channel to return immediately, either by throwing an exception or by returning normally.

Annotations

@Override

Exceptions

IOException:: If an I/O error occurs while closing the channel

mark	back to summary
private static int mark(ByteArrayInputStream in)

pos	back to summary
private static int pos(ByteArrayInputStream in)

position	back to summary
public long position() Implements java.nio.channels.SeekableByteChannel.position. Doc from java.nio.channels.SeekableByteChannel.position. Returns this channel's position. Returns:long This channel's position, a non-negative integer counting the number of bytes from the beginning of the entity to the current position

position

back to summary

public long position()

Implements java.nio.channels.SeekableByteChannel.position.

Doc from java.nio.channels.SeekableByteChannel.position.

Returns this channel's position.

Returns:long: This channel's position, a non-negative integer counting the number of bytes from the beginning of the entity to the current position

position back to summary

position	back to summary
public synchronized SeekableByteChannel position(long newPosition) throws IOException Implements java.nio.channels.SeekableByteChannel.position. Doc from java.nio.channels.SeekableByteChannel.position. Sets this channel's position. Setting the position to a value that is greater than the current size is legal but does not change the size of the entity. A later attempt to read bytes at such a position will immediately return an end-of-file indication. A later attempt to write bytes at such a position will cause the entity to grow to accommodate the new bytes; the values of any bytes between the previous end-of-file and the newly-written bytes are unspecified. Setting the channel's position is not recommended when connected to an entity, typically a file, that is opened with the `APPEND` option. When opened for append, the position is first advanced to the end before writing. Parameters newPosition:long The new position, a non-negative integer counting the number of bytes from the beginning of the entity Returns:SeekableByteChannel This channel Exceptions IOException: If some other I/O error occurs

public synchronized SeekableByteChannel position(long newPosition) throws IOException

Implements java.nio.channels.SeekableByteChannel.position.

Doc from java.nio.channels.SeekableByteChannel.position.

Sets this channel's position.

Setting the position to a value that is greater than the current size is legal but does not change the size of the entity. A later attempt to read bytes at such a position will immediately return an end-of-file indication. A later attempt to write bytes at such a position will cause the entity to grow to accommodate the new bytes; the values of any bytes between the previous end-of-file and the newly-written bytes are unspecified.

Setting the channel's position is not recommended when connected to an entity, typically a file, that is opened with the APPEND option. When opened for append, the position is first advanced to the end before writing.

Parameters

newPosition:long: The new position, a non-negative integer counting the number of bytes from the beginning of the entity

Returns:SeekableByteChannel

This channel

Exceptions

IOException:: If some other I/O error occurs

read back to summary

read	back to summary
public synchronized int read(ByteBuffer target) throws IOException Implements java.nio.channels.ReadableByteChannel.read, java.nio.channels.SeekableByteChannel.read. Doc from java.nio.channels.ReadableByteChannel.read. 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` `<=` n `<=` 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 `+` n `-` `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 `+` 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. Parameters target:ByteBuffer The buffer into which bytes are to be transferred Returns:int The number of bytes read, possibly zero, or `-1` if the channel has reached end-of-stream Annotations @Override Exceptions IOException: If some other I/O error occurs

public synchronized int read(ByteBuffer target) throws IOException

Implements java.nio.channels.ReadableByteChannel.read, java.nio.channels.SeekableByteChannel.read.

Doc from java.nio.channels.ReadableByteChannel.read.

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 <= n <= 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 + n - 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 + 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.

Parameters

target:ByteBuffer: The buffer into which bytes are to be transferred

Returns:int

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

Annotations

@Override

Exceptions

IOException:: If some other I/O error occurs

readIntField	back to summary
private static int readIntField(ByteArrayInputStream self, Field field)

size	back to summary
public long size() Implements java.nio.channels.SeekableByteChannel.size. Doc from java.nio.channels.SeekableByteChannel.size. Returns the current size of entity to which this channel is connected. Returns:long The current size, measured in bytes

size

back to summary

public long size()

Implements java.nio.channels.SeekableByteChannel.size.

Doc from java.nio.channels.SeekableByteChannel.size.

Returns the current size of entity to which this channel is connected.

Returns:long: The current size, measured in bytes

truncate back to summary

truncate	back to summary
public SeekableByteChannel truncate(long size) throws IOException Implements java.nio.channels.SeekableByteChannel.truncate. Doc from java.nio.channels.SeekableByteChannel.truncate. Truncates the entity, to which this channel is connected, to the given size. If the given size is less than the current size then the entity is truncated, discarding any bytes beyond the new end. If the given size is greater than or equal to the current size then the entity is not modified. In either case, if the current position is greater than the given size then it is set to that size. An implementation of this interface may prohibit truncation when connected to an entity, typically a file, opened with the `APPEND` option. Parameters size:long The new size, a non-negative byte count Returns:SeekableByteChannel This channel Exceptions IOException: If some other I/O error occurs

public SeekableByteChannel truncate(long size) throws IOException

Implements java.nio.channels.SeekableByteChannel.truncate.

Doc from java.nio.channels.SeekableByteChannel.truncate.

Truncates the entity, to which this channel is connected, to the given size.

If the given size is less than the current size then the entity is truncated, discarding any bytes beyond the new end. If the given size is greater than or equal to the current size then the entity is not modified. In either case, if the current position is greater than the given size then it is set to that size.

An implementation of this interface may prohibit truncation when connected to an entity, typically a file, opened with the APPEND option.

Parameters

size:long: The new size, a non-negative byte count

Returns:SeekableByteChannel

This channel

Exceptions

IOException:: If some other I/O error occurs

write back to summary

write	back to summary
public int write(ByteBuffer src) throws IOException Implements java.nio.channels.SeekableByteChannel.write. Doc from java.nio.channels.SeekableByteChannel.write. Writes a sequence of bytes to this channel from the given buffer. Bytes are written starting at this channel's current position, unless the channel is connected to an entity such as a file that is opened with the `APPEND` option, in which case the position is first advanced to the end. The entity to which the channel is connected is grown, if necessary, to accommodate the written bytes, and then the position is updated with the number of bytes actually written. Otherwise this method behaves exactly as specified by the `WritableByteChannel` interface. Parameters src:ByteBuffer Doc from java.nio.channels.WritableByteChannel.write. The buffer from which bytes are to be retrieved Returns:int Doc from java.nio.channels.WritableByteChannel.write. The number of bytes written, possibly zero Exceptions IOException: Doc from java.nio.channels.WritableByteChannel.write. If some other I/O error occurs

public int write(ByteBuffer src) throws IOException

Implements java.nio.channels.SeekableByteChannel.write.

Doc from java.nio.channels.SeekableByteChannel.write.

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

Bytes are written starting at this channel's current position, unless the channel is connected to an entity such as a file that is opened with the APPEND option, in which case the position is first advanced to the end. The entity to which the channel is connected is grown, if necessary, to accommodate the written bytes, and then the position is updated with the number of bytes actually written. Otherwise this method behaves exactly as specified by the WritableByteChannel interface.

Parameters

src:ByteBuffer

Doc from java.nio.channels.WritableByteChannel.write.

The buffer from which bytes are to be retrieved

Returns:int