org.apache.ignite.cache.eviction.fifo

Class FifoEvictionPolicy<K,V>

java.lang.Object

org.apache.ignite.cache.eviction.fifo.FifoEvictionPolicy<K,V>

All Implemented Interfaces:

Externalizable, Serializable, EvictionPolicy<K,V>, FifoEvictionPolicyMBean

public class FifoEvictionPolicy<K,V>
extends Object
implements EvictionPolicy<K,V>, FifoEvictionPolicyMBean, Externalizable

Eviction policy based on First In First Out (FIFO) algorithm and supports batch eviction.

The eviction starts when the cache size becomes batchSize elements greater than the maximum size. batchSize elements will be evicted in this case. The default batchSize value is 1.

This implementation is very efficient since it does not create any additional table-like data structures. The FIFO ordering information is maintained by attaching ordering metadata to cache entries.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
FifoEvictionPolicy() Constructs FIFO eviction policy with all defaults.
FifoEvictionPolicy(int max) Constructs FIFO eviction policy with maximum size.
FifoEvictionPolicy(int max, int batchSize) Constructs FIFO eviction policy with maximum size and given batch size.

Method Summary

Methods

Modifier and Type	Method and Description
int	getBatchSize() Gets batch size.
int	getCurrentSize() Gets current queue size.
int	getMaxSize() Gets maximum allowed size of cache before entry will start getting evicted.
void	onEntryAccessed(boolean rmv, EvictableEntry<K,V> entry) Callback for whenever entry is accessed.
Collection<EvictableEntry<K,V>>	queue() Gets read-only view on internal FIFO queue in proper order.
void	readExternal(ObjectInput in)
void	setBatchSize(int batchSize) Sets batch size.
void	setMaxSize(int max) Sets maximum allowed size of cache before entry will start getting evicted.
String	toString()
void	writeExternal(ObjectOutput out)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

FifoEvictionPolicy

public FifoEvictionPolicy()

Constructs FIFO eviction policy with all defaults.

FifoEvictionPolicy

public FifoEvictionPolicy(int max)

Constructs FIFO eviction policy with maximum size. Empty entries are allowed.

Parameters:

max - Maximum allowed size of cache before entry will start getting evicted.

FifoEvictionPolicy

public FifoEvictionPolicy(int max,
                  int batchSize)

Constructs FIFO eviction policy with maximum size and given batch size. Empty entries are allowed.

Parameters:

max - Maximum allowed size of cache before entry will start getting evicted.

batchSize - Batch size.

Method Detail

getMaxSize

public int getMaxSize()

Gets maximum allowed size of cache before entry will start getting evicted.

Specified by:

getMaxSize in interface FifoEvictionPolicyMBean

Returns:

Maximum allowed size of cache before entry will start getting evicted.

setMaxSize

public void setMaxSize(int max)

Sets maximum allowed size of cache before entry will start getting evicted.

Specified by:

setMaxSize in interface FifoEvictionPolicyMBean

Parameters:

max - Maximum allowed size of cache before entry will start getting evicted.

getBatchSize

public int getBatchSize()

Gets batch size.

Specified by:

getBatchSize in interface FifoEvictionPolicyMBean

Returns:

batch size.

setBatchSize

public void setBatchSize(int batchSize)

Sets batch size.

Specified by:

setBatchSize in interface FifoEvictionPolicyMBean

Parameters:

batchSize - Batch size.

getCurrentSize

public int getCurrentSize()

Gets current queue size.

Specified by:

getCurrentSize in interface FifoEvictionPolicyMBean

Returns:

Current queue size.

queue

public Collection<EvictableEntry<K,V>> queue()

Gets read-only view on internal FIFO queue in proper order.

Returns:

Read-only view ono internal 'FIFO' queue.

onEntryAccessed

public void onEntryAccessed(boolean rmv,
                   EvictableEntry<K,V> entry)

Callback for whenever entry is accessed.

Specified by:

onEntryAccessed in interface EvictionPolicy<K,V>

Parameters:

rmv - True if entry has been removed, false otherwise.

entry - Accessed entry.

writeExternal

public void writeExternal(ObjectOutput out)
                   throws IOException

Specified by:

writeExternal in interface Externalizable

Throws:

IOException

readExternal

public void readExternal(ObjectInput in)
                  throws IOException,
                         ClassNotFoundException

Specified by:

readExternal in interface Externalizable

Throws:

IOException

ClassNotFoundException

toString

public String toString()

Overrides:

toString in class Object