StorageDataFileItemIterator.BufferProvider.ConstantSizedBufferProvider (MicroStream API)

java.lang.Object
- one.microstream.storage.types.StorageDataFileItemIterator.BufferProvider.ConstantSizedBufferProvider

All Implemented Interfaces:

StorageDataFileItemIterator.BufferProvider

Enclosing interface:

StorageDataFileItemIterator.BufferProvider
```
public static final class StorageDataFileItemIterator.BufferProvider.ConstantSizedBufferProvider
extends Object
implements StorageDataFileItemIterator.BufferProvider
```
Simple implementation that provides always the same ByteBuffer instance with a fixed size. This is sufficient for reading all entity headers and having the data available for caching of "small" entities. Normally, the buffer size is downwards capped at the system's page size which also proved to be the optimal buffer size (anything large gives no significant advantage, anything lower dramatically reduces performance. Both not surprising, given the fundamental meaning of a page size).

Nested Class Summary
- Nested classes/interfaces inherited from interface one.microstream.storage.types.StorageDataFileItemIterator.BufferProvider
  StorageDataFileItemIterator.BufferProvider.ConstantSizedBufferProvider

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`ByteBuffer`	`provideBuffer(ByteBuffer byteBuffer, long nextEntityLength)`	The passed and returned byte buffer instances are guaranteed to be direct bytebuffer.
`ByteBuffer`	`provideInitialBuffer()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface one.microstream.storage.types.StorageDataFileItemIterator.BufferProvider
cleanUp

- Method Detail
  - provideInitialBuffer
```
public final ByteBuffer provideInitialBuffer()
```
    Specified by:
    
    provideInitialBuffer in interface StorageDataFileItemIterator.BufferProvider
  - provideBuffer
```
public final ByteBuffer provideBuffer(ByteBuffer byteBuffer,
                                      long nextEntityLength)
```
    Description copied from interface: StorageDataFileItemIterator.BufferProvider
    
    The passed and returned byte buffer instances are guaranteed to be direct bytebuffer. This has to be ensured via contract instead of proper typing because of the lack of competent typing in the JDK. All byte buffer instances passed to this method are guaranteed to have been created by it. See StorageDataFileItemIterator.BufferProvider.provideInitialBuffer().
    
    Specified by:
    
    provideBuffer in interface StorageDataFileItemIterator.BufferProvider
    
    Parameters:
    
    byteBuffer - the direct byte buffer used so far.
    
    nextEntityLength - the length of the next entity to be read to the buffer.
    
    Returns:
    
    a byte buffer of appropriate size to hold the next entity's data to be processed sufficiently.