MemoryAllocator (druid-processing 30.0.1 API)

All Known Implementing Classes:

ArenaMemoryAllocator, HeapMemoryAllocator
```
public interface MemoryAllocator
```
Allocator of WritableMemory. Not thread safe.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`Optional<ResourceHolder<org.apache.datasketches.memory.WritableMemory>>`	`allocate(long size)`	Allocates a block of memory of capacity {@param size}.
`long`	`available()`	Returns the number of bytes available for allocations.
`long`	`capacity()`	Returns the number of bytes managed by this allocator.

- Method Detail
  - allocate
```
Optional<ResourceHolder<org.apache.datasketches.memory.WritableMemory>> allocate(long size)
```
    Allocates a block of memory of capacity {@param size}. Returns empty if no more memory is available. The memory can be freed by closing the returned ResourceHolder. The returned WritableMemory object will use little-endian byte order.
  - available
```
long available()
```
    Returns the number of bytes available for allocations. May return Long.MAX_VALUE if there is no inherent limit. This generally does not mean you can actually allocate 9 exabytes.
  - capacity
```
long capacity()
```
    Returns the number of bytes managed by this allocator. When no memory has been allocated yet, this is identical to available(). May return Long.MAX_VALUE if there is no inherent limit. This generally does not mean you can actually allocate 9 exabytes.