UnpoolDirectAllocator

Allocate a Buffer of the given size in bytes. This method may throw an OutOfMemoryError if there is not enough free memory available to allocate a Buffer of the requested size.

The buffer will use big endian byte order.

Note: unlike the JDK ByteBuffers, Netty Buffers are not guaranteed to be zeroed when allocated. In other words, the memory of a newly allocated buffer may contain garbage data from prior allocations, and the memory is likewise not guaranteed to be erased when the buffer is closed. If the data is sensitive and needs to be overwritten when the buffer is closed, then the buffer should be allocated with the SensitiveBufferAllocator.

Determine if this allocator is allocate direct memory or heap memory.