All Superinterfaces:

ReferenceCounted

All Known Implementing Classes:

DefaultFileRegion
```
public interface FileRegion
extends ReferenceCounted
```
A region of a file that is sent via a Channel which supports zero-copy file transfer.
Upgrade your JDK / JRE
FileChannel.transferTo(long, long, WritableByteChannel) has at least four known bugs in the old versions of Sun JDK and perhaps its derived ones. Please upgrade your JDK to 1.6.0_18 or later version if you are going to use zero-copy file transfer.
- 5103988 - FileChannel.transferTo() should return -1 for EAGAIN instead throws IOException
- 6253145 - FileChannel.transferTo() on Linux fails when going beyond 2GB boundary
- 6427312 - FileChannel.transferTo() throws IOException "system call interrupted"
- 6470086 - FileChannel.transferTo(2147483647, 1, channel) causes "Value too large" exception
Check your operating system and JDK / JRE
If your operating system (or JDK / JRE) does not support zero-copy file transfer, sending a file with FileRegion might fail or yield worse performance. For example, sending a large file doesn't work well in Windows.
Not all transports support it

Method Summary

All Methods Instance Methods Abstract Methods Deprecated Methods
Modifier and Type	Method	Description
`long`	`count()`	Returns the number of bytes to transfer.
`long`	`position()`	Returns the offset in the file where the transfer began.
`FileRegion`	`retain()`	Increases the reference count by `1`.
`FileRegion`	`retain(int increment)`	Increases the reference count by the specified `increment`.
`FileRegion`	`touch()`	Records the current access location of this object for debugging purposes.
`FileRegion`	`touch(Object hint)`	Records the current access location of this object with an additional arbitrary information for debugging purposes.
`long`	`transfered()`	Deprecated. Use `transferred()` instead.
`long`	`transferred()`	Returns the bytes which was transferred already.
`long`	`transferTo(WritableByteChannel target, long position)`	Transfers the content of this file region to the specified channel.

Methods inherited from interface io.netty5.util.ReferenceCounted
refCnt, release, release

- Method Detail
  - position
```
long position()
```
    Returns the offset in the file where the transfer began.
  - transfered
```
@Deprecated
long transfered()
```
    Deprecated.
    Use transferred() instead.
    
    Returns the bytes which was transferred already.
  - transferred
```
long transferred()
```
    Returns the bytes which was transferred already.
  - count
```
long count()
```
    Returns the number of bytes to transfer.
  - transferTo
```
long transferTo(WritableByteChannel target,
                long position)
         throws IOException
```
    Transfers the content of this file region to the specified channel.
    
    Parameters:
    
    target - the destination of the transfer
    
    position - the relative offset of the file where the transfer begins from. For example, 0 will make the transfer start from position()th byte and count() - 1 will make the last byte of the region transferred.
    
    Throws:
    
    IOException
  - retain
```
FileRegion retain()
```
    Description copied from interface: ReferenceCounted
    
    Increases the reference count by 1.
    
    Specified by:
    
    retain in interface ReferenceCounted
  - retain
```
FileRegion retain(int increment)
```
    Description copied from interface: ReferenceCounted
    
    Increases the reference count by the specified increment.
    
    Specified by:
    
    retain in interface ReferenceCounted
  - touch
```
FileRegion touch()
```
    Description copied from interface: ReferenceCounted
    
    Records the current access location of this object for debugging purposes. If this object is determined to be leaked, the information recorded by this operation will be provided to you via ResourceLeakDetector. This method is a shortcut to touch(null).
    
    Specified by:
    
    touch in interface ReferenceCounted
  - touch
```
FileRegion touch(Object hint)
```
    Description copied from interface: ReferenceCounted
    
    Records the current access location of this object with an additional arbitrary information for debugging purposes. If this object is determined to be leaked, the information recorded by this operation will be provided to you via ResourceLeakDetector.
    
    Specified by:
    
    touch in interface ReferenceCounted

Interface FileRegion

Upgrade your JDK / JRE

Check your operating system and JDK / JRE

Not all transports support it

Method Summary

Methods inherited from interface io.netty5.util.ReferenceCounted

Method Detail

position

transfered

transferred

count

transferTo

retain

retain

touch

touch