io.netty.channel.unix

Class IovArray

java.lang.Object

io.netty.channel.unix.IovArray

All Implemented Interfaces:

io.netty.channel.ChannelOutboundBuffer.MessageProcessor

public final class IovArray
extends Object
implements io.netty.channel.ChannelOutboundBuffer.MessageProcessor

Represent an array of struct array and so can be passed directly over via JNI without the need to do any more array copies. The buffers are written out directly into direct memory to match the struct iov. See also man writev.

 struct iovec {
   void  *iov_base;
   size_t iov_len;
 };
 

See also Efficient JNI programming IV: Wrapping native data objects.

Constructor Summary

Constructors

Constructor and Description
IovArray()

Method Summary

Modifier and Type	Method and Description
boolean	add(io.netty.buffer.ByteBuf buf) Add a ByteBuf to this IovArray.
void	clear()
int	count() Returns the number if iov entries.
long	maxBytes() Get the maximum amount of bytes that can be added to this IovArray via add(ByteBuf).
void	maxBytes(long maxBytes) Set the maximum amount of bytes that can be added to this IovArray via add(ByteBuf).
long	memoryAddress(int offset) Returns the memoryAddress for the given offset.
boolean	processMessage(Object msg)
void	release() Release the IovArray.
long	size() Returns the size in bytes

Methods inherited from class java.lang.Object

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

Constructor Detail

IovArray

public IovArray()

Method Detail

clear

public void clear()

add

public boolean add(io.netty.buffer.ByteBuf buf)

Add a ByteBuf to this IovArray.

Parameters:

buf - The ByteBuf to add.

Returns:

true if the entire ByteBuf has been added to this IovArray. Note in the event that ByteBuf is a CompositeByteBuf false may be returned even if some of the components have been added.

count

public int count()

Returns the number if iov entries.

size

public long size()

Returns the size in bytes

maxBytes

public void maxBytes(long maxBytes)

Set the maximum amount of bytes that can be added to this IovArray via add(ByteBuf).

This will not impact the existing state of the IovArray, and only applies to subsequent calls to add(ByteBuf).

In order to ensure some progress is made at least one ByteBuf will be accepted even if it's size exceeds this value.

Parameters:

maxBytes - the maximum amount of bytes that can be added to this IovArray via add(ByteBuf).

maxBytes

public long maxBytes()

Get the maximum amount of bytes that can be added to this IovArray via add(ByteBuf).

Returns:

the maximum amount of bytes that can be added to this IovArray via add(ByteBuf).

memoryAddress

public long memoryAddress(int offset)

Returns the memoryAddress for the given offset.

release

public void release()

Release the IovArray. Once release further using of it may crash the JVM!

processMessage

public boolean processMessage(Object msg)
                       throws Exception

Specified by:

processMessage in interface io.netty.channel.ChannelOutboundBuffer.MessageProcessor

Throws:

Exception