MemoryCacher (moleculer-java 1.2.21 API)

java.lang.Object
- services.moleculer.service.MoleculerComponent
- - services.moleculer.service.Middleware
  - - services.moleculer.cacher.Cacher
    - - services.moleculer.cacher.MemoryCacher

All Implemented Interfaces:

java.lang.Runnable, MetricConstants, MoleculerLifecycle
```
public class MemoryCacher
extends Cacher
implements java.lang.Runnable
```
On-heap memory cache. MemoryCacher is the fastest cache implementation in Moleculer. This can be a "distributed" cache, the content of the other node's cache is removable via events; the developer can send distributed events that erase the cache on the other nodes - but this is not automatic! Supports global and entry-level TTL configuration. Configuration properties:
- capacity: Maximum capacity per partition (must be a power of 2), defaults to 2048
- ttl: Expire time of entries in memory, in seconds (default: 0 = never expires)
- cleanup: Cleanup period, in seconds
Performance (small and large data): 5.5 million gets / second (per thread / core)
See Also:

RedisCacher, OHCacher

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

protected static class MemoryCacher.MemoryPartition

protected static class MemoryCacher.PartitionEntry

Nested Classes
Modifier and Type	Class and Description
`protected static class`	`MemoryCacher.MemoryPartition`
`protected static class`	`MemoryCacher.PartitionEntry`

Field Summary

Fields
Modifier and Type	Field and Description
`protected int`	`capacity` Maximum number of entries per partition
`protected int`	`cleanup` Cleanup period time, in SECONDS (0 = disable cleanup process)
`protected MetricCounter`	`counterClean`
`protected MetricCounter`	`counterDel`
`protected MetricCounter`	`counterExpired`
`protected MetricCounter`	`counterFound`
`protected MetricCounter`	`counterGet`
`protected MetricCounter`	`counterSet`
`protected java.util.HashMap<java.lang.String,MemoryCacher.MemoryPartition>`	`partitions`
`protected java.util.concurrent.locks.ReentrantReadWriteLock.ReadLock`	`readLock`
`protected java.util.concurrent.ScheduledFuture<?>`	`timer` Cancelable timer
`protected java.util.concurrent.atomic.AtomicBoolean`	`timerStarted`
`protected java.util.concurrent.atomic.AtomicBoolean`	`timerStopped`
`protected int`	`ttl` Expire time, in SECONDS (0 = never expires)
`protected boolean`	`useCloning` Do you need to make a copy of the returned values?
`protected java.util.concurrent.locks.ReentrantReadWriteLock.WriteLock`	`writeLock`

Fields inherited from class services.moleculer.cacher.Cacher
metrics

Fields inherited from class services.moleculer.service.MoleculerComponent
broker, logger, name

Fields inherited from interface services.moleculer.metrics.MetricConstants
MOLECULER_CACHER_CLEAN_TIME, MOLECULER_CACHER_CLEAN_TIME_DESC, MOLECULER_CACHER_CLEAN_TOTAL, MOLECULER_CACHER_CLEAN_TOTAL_DESC, MOLECULER_CACHER_DEL_TIME, MOLECULER_CACHER_DEL_TIME_DESC, MOLECULER_CACHER_DEL_TOTAL, MOLECULER_CACHER_DEL_TOTAL_DESC, MOLECULER_CACHER_EXPIRED_TOTAL, MOLECULER_CACHER_EXPIRED_TOTAL_DESC, MOLECULER_CACHER_FOUND_TOTAL, MOLECULER_CACHER_FOUND_TOTAL_DESC, MOLECULER_CACHER_GET_TIME, MOLECULER_CACHER_GET_TIME_DESC, MOLECULER_CACHER_GET_TOTAL, MOLECULER_CACHER_GET_TOTAL_DESC, MOLECULER_CACHER_SET_TIME, MOLECULER_CACHER_SET_TIME_DESC, MOLECULER_CACHER_SET_TOTAL, MOLECULER_CACHER_SET_TOTAL_DESC, MOLECULER_CIRCUIT_BREAKER_HALF_OPENED_ACTIVE, MOLECULER_CIRCUIT_BREAKER_HALF_OPENED_ACTIVE_DESC, MOLECULER_CIRCUIT_BREAKER_OPENED_ACTIVE, MOLECULER_CIRCUIT_BREAKER_OPENED_ACTIVE_DESC, MOLECULER_CIRCUIT_BREAKER_OPENED_TOTAL, MOLECULER_CIRCUIT_BREAKER_OPENED_TOTAL_DESC, MOLECULER_EVENT_BROADCAST_TOTAL, MOLECULER_EVENT_BROADCAST_TOTAL_DESC, MOLECULER_EVENT_BROADCASTLOCAL_TOTAL, MOLECULER_EVENT_BROADCASTLOCAL_TOTAL_DESC, MOLECULER_EVENT_EMIT_TOTAL, MOLECULER_EVENT_EMIT_TOTAL_DESC, MOLECULER_EVENT_RECEIVED_ACTIVE, MOLECULER_EVENT_RECEIVED_ACTIVE_DESC, MOLECULER_EVENT_RECEIVED_ERROR_TOTAL, MOLECULER_EVENT_RECEIVED_ERROR_TOTAL_DESC, MOLECULER_EVENT_RECEIVED_TIME, MOLECULER_EVENT_RECEIVED_TIME_DESC, MOLECULER_EVENT_RECEIVED_TOTAL, MOLECULER_EVENT_RECEIVED_TOTAL_DESC, MOLECULER_EXECUTOR, MOLECULER_REQUEST_ACTIVE, MOLECULER_REQUEST_ACTIVE_DESC, MOLECULER_REQUEST_ERROR_TOTAL, MOLECULER_REQUEST_ERROR_TOTAL_DESC, MOLECULER_REQUEST_LEVELS, MOLECULER_REQUEST_LEVELS_DESC, MOLECULER_REQUEST_RETRY_ATTEMPTS_TOTAL, MOLECULER_REQUEST_RETRY_ATTEMPTS_TOTAL_DESC, MOLECULER_REQUEST_TIME, MOLECULER_REQUEST_TIME_DESC, MOLECULER_REQUEST_TIMEOUT_TOTAL, MOLECULER_REQUEST_TIMEOUT_TOTAL_DESC, MOLECULER_REQUEST_TOTAL, MOLECULER_REQUEST_TOTAL_DESC, MOLECULER_SCHEDULER, MOLECULER_TRANSIT_CONNECTED, MOLECULER_TRANSIT_CONNECTED_DESC, MOLECULER_TRANSIT_ORPHAN_RESPONSE_TOTAL, MOLECULER_TRANSIT_ORPHAN_RESPONSE_TOTAL_DESC, MOLECULER_TRANSIT_REQUESTS_ACTIVE, MOLECULER_TRANSIT_REQUESTS_ACTIVE_DESC, MOLECULER_TRANSIT_STREAMS_RECEIVE_ACTIVE, MOLECULER_TRANSIT_STREAMS_RECEIVE_ACTIVE_DESC, MOLECULER_TRANSPORTER_PACKETS_RECEIVED_BYTES, MOLECULER_TRANSPORTER_PACKETS_RECEIVED_BYTES_DESC, MOLECULER_TRANSPORTER_PACKETS_RECEIVED_TOTAL, MOLECULER_TRANSPORTER_PACKETS_RECEIVED_TOTAL_DESC, MOLECULER_TRANSPORTER_PACKETS_SENT_BYTES, MOLECULER_TRANSPORTER_PACKETS_SENT_BYTES_DESC, MOLECULER_TRANSPORTER_PACKETS_SENT_TOTAL, MOLECULER_TRANSPORTER_PACKETS_SENT_TOTAL_DESC

Constructor Summary

Constructors
Constructor and Description
`MemoryCacher()`
`MemoryCacher(int capacityPerPartition, int defaultTtl)`
`MemoryCacher(int capacityPerPartition, int defaultTtl, int cleanupSeconds)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`io.datatree.Promise`	`clean(java.lang.String match)` Cleans this cache.
`io.datatree.Promise`	`del(java.lang.String key)` Deletes a content from this cache.
`io.datatree.Promise`	`get(java.lang.String key)` Gets a cached content by a key.
`io.datatree.Promise`	`getCacheKeys()` Lists all keys of cached entries.
`int`	`getCapacity()`
`int`	`getCleanup()`
`protected MemoryCacher.MemoryPartition`	`getPartition(java.lang.String prefix)`
`int`	`getTtl()`
`boolean`	`isUseCloning()`
`protected int`	`partitionPosition(java.lang.String key, boolean throwErrorIfMissing)`
`void`	`run()`
`io.datatree.Promise`	`set(java.lang.String key, io.datatree.Tree value, int ttl)` Sets a content by key into the cache.
`void`	`setCapacity(int capacity)`
`void`	`setCleanup(int cleanup)`
`void`	`setTtl(int ttl)`
`void`	`setUseCloning(boolean useCloning)`
`void`	`started(ServiceBroker broker)` Initializes cacher instance.
`protected void`	`startTimer(int entryTTL)`
`void`	`stopped()`

Methods inherited from class services.moleculer.cacher.Cacher
appendToKey, appendTree, getCacheKey, install, isCachingDisabledByTheContext, serializeKey

Methods inherited from class services.moleculer.service.MoleculerComponent
getBroker, getLogger, getName

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

- Field Detail
  - capacity
```
protected int capacity
```
    Maximum number of entries per partition
  - ttl
```
protected int ttl
```
    Expire time, in SECONDS (0 = never expires)
  - cleanup
```
protected int cleanup
```
    Cleanup period time, in SECONDS (0 = disable cleanup process)
  - useCloning
```
protected boolean useCloning
```
    Do you need to make a copy of the returned values? Cloning the values is much safer, but little bit slower. If the services work with common objects, they can modify the cached object. If you turn off cloning, the cache will be faster, but you need to be careful NOT TO CHANGE the values from the cache!
  - readLock
```
protected final java.util.concurrent.locks.ReentrantReadWriteLock.ReadLock readLock
```
  - writeLock
```
protected final java.util.concurrent.locks.ReentrantReadWriteLock.WriteLock writeLock
```
  - partitions
```
protected final java.util.HashMap<java.lang.String,MemoryCacher.MemoryPartition> partitions
```
  - timer
```
protected volatile java.util.concurrent.ScheduledFuture<?> timer
```
    Cancelable timer
  - timerStarted
```
protected java.util.concurrent.atomic.AtomicBoolean timerStarted
```
  - timerStopped
```
protected java.util.concurrent.atomic.AtomicBoolean timerStopped
```
  - counterExpired
```
protected MetricCounter counterExpired
```
  - counterGet
```
protected MetricCounter counterGet
```
  - counterSet
```
protected MetricCounter counterSet
```
  - counterDel
```
protected MetricCounter counterDel
```
  - counterClean
```
protected MetricCounter counterClean
```
  - counterFound
```
protected MetricCounter counterFound
```
- Constructor Detail
  - MemoryCacher
```
public MemoryCacher()
```
  - MemoryCacher
```
public MemoryCacher(int capacityPerPartition,
                    int defaultTtl)
```
  - MemoryCacher
```
public MemoryCacher(int capacityPerPartition,
                    int defaultTtl,
                    int cleanupSeconds)
```
- Method Detail
  - started
```
public void started(ServiceBroker broker)
             throws java.lang.Exception
```
    Initializes cacher instance.
    
    Specified by:
    
    started in interface MoleculerLifecycle
    
    Overrides:
    
    started in class Cacher
    
    Parameters:
    
    broker - parent ServiceBroker
    
    Throws:
    
    java.lang.Exception
  - startTimer
```
protected void startTimer(int entryTTL)
```
  - run
```
public void run()
```
    Specified by:
    
    run in interface java.lang.Runnable
  - stopped
```
public void stopped()
```
    Specified by:
    
    stopped in interface MoleculerLifecycle
    
    Overrides:
    
    stopped in class MoleculerComponent
  - get
```
public io.datatree.Promise get(java.lang.String key)
```
    Description copied from class: Cacher
    
    Gets a cached content by a key.
    
    Specified by:
    
    get in class Cacher
    
    Parameters:
    
    key - cache key
    
    Returns:
    
    Promise with cached value (or null, the returned Promise also can be null)
  - getPartition
```
protected MemoryCacher.MemoryPartition getPartition(java.lang.String prefix)
```
  - set
```
public io.datatree.Promise set(java.lang.String key,
                               io.datatree.Tree value,
                               int ttl)
```
    Description copied from class: Cacher
    
    Sets a content by key into the cache.
    
    Specified by:
    
    set in class Cacher
    
    Parameters:
    
    key - cache key
    
    value - new value
    
    ttl - optional TTL of entry (0 == use default TTL)
    
    Returns:
    
    Promise with empty value
  - del
```
public io.datatree.Promise del(java.lang.String key)
```
    Description copied from class: Cacher
    
    Deletes a content from this cache.
    
    Specified by:
    
    del in class Cacher
    
    Parameters:
    
    key - cache key
    
    Returns:
    
    Promise with empty value
  - clean
```
public io.datatree.Promise clean(java.lang.String match)
```
    Description copied from class: Cacher
    
    Cleans this cache. Removes every key by a match string. The default match string is "**".
    
    Specified by:
    
    clean in class Cacher
    
    Parameters:
    
    match - regex
    
    Returns:
    
    Promise with empty value
  - partitionPosition
```
protected int partitionPosition(java.lang.String key,
                                boolean throwErrorIfMissing)
```
  - getCacheKeys
```
public io.datatree.Promise getCacheKeys()
```
    Lists all keys of cached entries.
    
    Specified by:
    
    getCacheKeys in class Cacher
    
    Returns:
    
    a Tree object with a "keys" array.
  - getCapacity
```
public int getCapacity()
```
  - setCapacity
```
public void setCapacity(int capacity)
```
  - getTtl
```
public int getTtl()
```
  - setTtl
```
public void setTtl(int ttl)
```
  - getCleanup
```
public int getCleanup()
```
  - setCleanup
```
public void setCleanup(int cleanup)
```
  - isUseCloning
```
public boolean isUseCloning()
```
  - setUseCloning
```
public void setUseCloning(boolean useCloning)
```

Class MemoryCacher

Nested Class Summary

Field Summary

Fields inherited from class services.moleculer.cacher.Cacher

Fields inherited from class services.moleculer.service.MoleculerComponent

Fields inherited from interface services.moleculer.metrics.MetricConstants

Constructor Summary

Method Summary

Methods inherited from class services.moleculer.cacher.Cacher

Methods inherited from class services.moleculer.service.MoleculerComponent

Methods inherited from class java.lang.Object

Field Detail

capacity

ttl

cleanup

useCloning

readLock

writeLock

partitions

timer

timerStarted

timerStopped

counterExpired

counterGet

counterSet

counterDel

counterClean

counterFound

Constructor Detail

MemoryCacher

MemoryCacher

MemoryCacher

Method Detail

started

startTimer

run

stopped

get

getPartition

set

del

clean

partitionPosition

getCacheKeys

getCapacity

setCapacity

getTtl

setTtl

getCleanup

setCleanup

isUseCloning

setUseCloning