Package org.apache.qpid.protonj2.buffer

Interface ProtonBufferComponentAccessor

All Superinterfaces:

AutoCloseable

All Known Implementing Classes:

Netty4ToProtonBufferAdapter, Netty5ToProtonBufferAdapter, ProtonByteArrayBuffer

public interface ProtonBufferComponentAccessor
extends AutoCloseable

Provides a way of accessing the internal components of a ProtonBuffer which can be used to gain access to underlying buffer internals for IO or other low level buffer operations.

A component access object is not meant to have a long life-span as it can prevent the quick cleanup of buffer resources. Likewise the access object must be closed upon completion of the access if proper resource cleanup is to occur as the object itself ensure that there is concrete referencing of the buffer preventing a JVM GC of the object should the user discard the buffer before the access object has been discarded.

The general usage of the component access object should be within a try-with-resource block as follows:

   try (ProtonBufferComponentAccessor accessor = buffer.componentAccessor()) {
      for (ProtonBufferComponent component : accessor.readableComponents()) {
         // Access logic here....
      }
   }
 
 

Or an alternative that does not create an iterator for walking the list of available ProtonBufferComponents would look as follows:

   try (ProtonBufferComponentAccessor accessor = buffer.componentAccessor()) {
      for (ProtonBufferComponent component = accessor.first(); component != null; component = accessor.next()) {
         // Access logic here....
      }
   }
 
 

Method Summary

Modifier and Type	Method	Description
void	close()	Safe to call close in all cases the close will not throw.
default Iterator<ProtonBufferComponent>	componentIterator()
ProtonBufferComponent	first()	Returns the first component that this access object provides which resets the iteration state to the beginning.
default ProtonBufferComponent	firstReadable()	Returns the first readable component that this access object provides which resets the iteration state to the beginning.
default ProtonBufferComponent	firstWritable()	Returns the first readable component that this access object provides which resets the iteration state to the beginning.
ProtonBufferComponent	next()	Returns the next component that this access object provides which can be null if either the first method has never been called or the access of components has reached the end of the chain of buffer components that this access object is assigned to.
default ProtonBufferComponent	nextReadable()
default ProtonBufferComponent	nextWritable()
default Iterator<ProtonBufferComponent>	readableComponentIterator()
default Iterator<ProtonBufferComponent>	writableComponentIterator()

Method Details

close

void close()

Safe to call close in all cases the close will not throw.

Specified by:

close in interface AutoCloseable

first

ProtonBufferComponent first()

Returns the first component that this access object provides which resets the iteration state to the beginning.

Returns:

the first component in the sequence of ProtonBufferComponent instance.

firstReadable

default ProtonBufferComponent firstReadable()

Returns the first readable component that this access object provides which resets the iteration state to the beginning.

Returns:

the first readable component in the sequence of ProtonBufferComponent instance.

firstWritable

default ProtonBufferComponent firstWritable()

Returns the first readable component that this access object provides which resets the iteration state to the beginning.

Returns:

the first readable component in the sequence of ProtonBufferComponent instance.

next

ProtonBufferComponent next()

Returns the next component that this access object provides which can be null if either the first method has never been called or the access of components has reached the end of the chain of buffer components that this access object is assigned to.

Returns:

the first component in the sequence of ProtonBufferComponent instance.

nextReadable

default ProtonBufferComponent nextReadable()

Returns:

the next readable ProtonBufferComponent in the current chain.

nextWritable

default ProtonBufferComponent nextWritable()

Returns:

the next readable ProtonBufferComponent in the current chain.

componentIterator

default Iterator<ProtonBufferComponent> componentIterator()

Returns:

an Iterator that traverses all components within the ProtonBuffer

readableComponentIterator

default Iterator<ProtonBufferComponent> readableComponentIterator()

Returns:

an Iterator that traverses all readable components within the ProtonBuffer

writableComponentIterator

default Iterator<ProtonBufferComponent> writableComponentIterator()

Returns:

an Iterator that traverses all writable components within the ProtonBuffer