package org.infinispan.container.offheap;
import org.infinispan.commons.marshall.WrappedBytes;
import org.infinispan.container.entries.InternalCacheEntry;
import org.infinispan.metadata.Metadata;
/**
* Factory that can create {@link InternalCacheEntry} objects that use off-heap heap memory. These are stored by
* a long to symbolize the memory address.
* @author wburns
* @since 9.0
*/
public interface OffHeapEntryFactory {
/**
* Creates an off heap entry using the provided key value and metadata
* @param key the key to use
* @param value the value to use
* @param metadata the metadata to use
* @return the address of where the entry was created
*/
long create(WrappedBytes key, WrappedBytes value, Metadata metadata);
/**
* Returns how many bytes in memory this address location uses assuming it is an {@link InternalCacheEntry}
* @param address the address of the entry
* @return how many bytes this address was allocated as
*/
long determineSize(long address);
/**
* Returns the address to the next linked pointer if there is one for this bucket or 0 if there isn't one
* @param address the address of the entry
* @return the next address entry for this bucket or 0
*/
long getNextLinkedPointerAddress(long address);
/**
* Called to update the next pointer index when a collision occurs requiring a linked list within the entries
* themselves
* @param address the address of the entry to update
* @param value the value of the linked node to set
*/
void updateNextLinkedPointerAddress(long address, long value);
/**
* Returns the hashCode of the address. This
* @param address the address of the entry
* @return the has code of the entry
*/
int getHashCodeForAddress(long address);
/**
* Create an entry from the off heap pointer
* @param address the address of the entry to read
* @return the entry created on heap from off heap
*/
InternalCacheEntry<WrappedBytes, WrappedBytes> fromMemory(long address);
/**
* Returns the key for the given address
* @param address the address pointer to find the key of
* @return the key of the given address pointer
*/
WrappedBytes getKey(long address);
/**
* Returns whether the given key as bytes is the same key as the key stored in the entry for the given address.
* @param address the address of the entry's key to check
* @param wrappedBytes the key to check equality with
* @return whether or not the keys are equal
*/
boolean equalsKey(long address, WrappedBytes wrappedBytes);
}