org.apache.tomcat.util.net

Class NioChannel

java.lang.Object

org.apache.tomcat.util.net.NioChannel

All Implemented Interfaces:

Closeable, AutoCloseable, ByteChannel, Channel, GatheringByteChannel, ReadableByteChannel, ScatteringByteChannel, WritableByteChannel

Direct Known Subclasses:

SecureNioChannel

public class NioChannel
extends Object
implements ByteChannel, ScatteringByteChannel, GatheringByteChannel

Base class for a SocketChannel wrapper used by the endpoint. This way, logic for an SSL socket channel remains the same as for a non SSL, making sure we don't need to code for any exception cases.

Version:

1.0

Field Summary

Fields

Modifier and Type	Field and Description
protected SocketBufferHandler	bufHandler
protected static ByteBuffer	emptyBuf
protected SocketChannel	sc
protected static StringManager	sm
protected NioEndpoint.NioSocketWrapper	socketWrapper

Constructor Summary

Constructors

Constructor and Description
NioChannel(SocketBufferHandler bufHandler)

Method Summary

Modifier and Type	Method and Description
protected void	checkInterruptStatus() This method should be used to check the interrupt status before attempting a write.
void	close() Closes this channel.
void	close(boolean force) Close the connection.
boolean	flush(boolean block, Selector s, long timeout) Returns true if the network buffer has been flushed out and is empty.
boolean	flushOutbound() Return true if the buffer wrote data.
void	free() Free the channel memory
protected ApplicationBufferHandler	getAppReadBufHandler()
SocketBufferHandler	getBufHandler()
SocketChannel	getIOChannel()
int	getOutboundRemaining()
int	handshake(boolean read, boolean write) Performs SSL handshake hence is a no-op for the non-secure implementation.
boolean	isClosing()
boolean	isHandshakeComplete()
boolean	isOpen() Tells whether or not this channel is open.
int	read(ByteBuffer dst) Reads a sequence of bytes from this channel into the given buffer.
long	read(ByteBuffer[] dsts)
long	read(ByteBuffer[] dsts, int offset, int length)
void	reset(SocketChannel channel, NioEndpoint.NioSocketWrapper socketWrapper) Reset the channel
void	setAppReadBufHandler(ApplicationBufferHandler handler)
String	toString()
int	write(ByteBuffer src) Writes a sequence of bytes to this channel from the given buffer.
long	write(ByteBuffer[] srcs)
long	write(ByteBuffer[] srcs, int offset, int length)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

sm

protected static final StringManager sm

emptyBuf

protected static final ByteBuffer emptyBuf

bufHandler

protected final SocketBufferHandler bufHandler

sc

protected SocketChannel sc

socketWrapper

protected NioEndpoint.NioSocketWrapper socketWrapper

Constructor Detail

NioChannel

public NioChannel(SocketBufferHandler bufHandler)

Method Detail

reset

public void reset(SocketChannel channel,
                  NioEndpoint.NioSocketWrapper socketWrapper)
           throws IOException

Reset the channel

Parameters:

channel - the socket channel

socketWrapper - the socket wrapper

Throws:

IOException - If a problem was encountered resetting the channel

free

public void free()

Free the channel memory

flush

public boolean flush(boolean block,
                     Selector s,
                     long timeout)
              throws IOException

Returns true if the network buffer has been flushed out and is empty.

Parameters:

block - Unused. May be used when overridden

s - Unused. May be used when overridden

timeout - Unused. May be used when overridden

Returns:

Always returns true since there is no network buffer in the regular channel

Throws:

IOException - Never for non-secure channel

close

public void close()
           throws IOException

Closes this channel.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Channel

Throws:

IOException - If an I/O error occurs

close

public void close(boolean force)
           throws IOException

Close the connection.

Parameters:

force - Should the underlying socket be forcibly closed?

Throws:

IOException - If closing the secure channel fails.

isOpen

public boolean isOpen()

Tells whether or not this channel is open.

Specified by:

isOpen in interface Channel

Returns:

true if, and only if, this channel is open

write

public int write(ByteBuffer src)
          throws IOException

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

Specified by:

write in interface WritableByteChannel

Parameters:

src - The buffer from which bytes are to be retrieved

Returns:

The number of bytes written, possibly zero

Throws:

IOException - If some other I/O error occurs

write

public long write(ByteBuffer[] srcs)
           throws IOException

Specified by:

write in interface GatheringByteChannel

Throws:

IOException

write

public long write(ByteBuffer[] srcs,
                  int offset,
                  int length)
           throws IOException

Specified by:

write in interface GatheringByteChannel

Throws:

IOException

read

public int read(ByteBuffer dst)
         throws IOException

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

Specified by:

read in interface ReadableByteChannel

Parameters:

dst - 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

Throws:

IOException - If some other I/O error occurs

read

public long read(ByteBuffer[] dsts)
          throws IOException

Specified by:

read in interface ScatteringByteChannel

Throws:

IOException

read

public long read(ByteBuffer[] dsts,
                 int offset,
                 int length)
          throws IOException

Specified by:

read in interface ScatteringByteChannel

Throws:

IOException

getBufHandler

public SocketBufferHandler getBufHandler()

getIOChannel

public SocketChannel getIOChannel()

isClosing

public boolean isClosing()

isHandshakeComplete

public boolean isHandshakeComplete()

handshake

public int handshake(boolean read,
                     boolean write)
              throws IOException

Performs SSL handshake hence is a no-op for the non-secure implementation.

Parameters:

read - Unused in non-secure implementation

write - Unused in non-secure implementation

Returns:

Always returns zero

Throws:

IOException - Never for non-secure channel

toString

public String toString()

Overrides:

toString in class Object

getOutboundRemaining

public int getOutboundRemaining()

flushOutbound

public boolean flushOutbound()
                      throws IOException

Return true if the buffer wrote data. NO-OP for non-secure channel.

Returns:

Always returns false for non-secure channel

Throws:

IOException - Never for non-secure channel

checkInterruptStatus

protected void checkInterruptStatus()
                             throws IOException

This method should be used to check the interrupt status before attempting a write. If a thread has been interrupted and the interrupt has not been cleared then an attempt to write to the socket will fail. When this happens the socket is removed from the poller without the socket being selected. This results in a connection limit leak for NIO as the endpoint expects the socket to be selected even in error conditions.

Throws:

IOException - If the current thread was interrupted

setAppReadBufHandler

public void setAppReadBufHandler(ApplicationBufferHandler handler)

getAppReadBufHandler

protected ApplicationBufferHandler getAppReadBufHandler()