Tutorial de Memcached Java Client usando las bibliotecas whalin.Memcached-Java-Client y googlecode.xmemcached

Publicado: 2019-09-01
Tutorial del cliente Java de Memcached usando las bibliotecas whalin y googlecode.xmemcached

Este es un tutorial continuo sobre Memcached which is distributed memory object caching server . Aquí hay dos tutoriales anteriores antes de revisar este.

  • Cómo instalar y configurar Memcached
  • Tutorial del cliente Java de Memcached usando la biblioteca net.spy.spymemcached

En este tutorial, repasaremos Memcached Java Client utilizando los siguientes dos enfoques:

com.whalin.Memcached-Java-Client Library

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< dependency >
< groupId > com . whalin < / groupId >
< artifactId > Memcached - Java - Client < / artifactId >
< version > 3.0.2 < / version >
< / dependency >

Biblioteca com.googlecode.xmemcached

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< dependency >
< groupId > com . googlecode . xmemcached < / groupId >
< artifactId > xmemcached < / artifactId >
< version > 2.4.5 < / version >
< / dependency >

Simplemente agregue estas dos dependencias expertas al archivo pom.xml de su proyecto para obtener la biblioteca en su espacio de trabajo de Eclipse.

Aquí hay un programa CrunchifyComWhalinXMemcachedClient.java completo con todos los detalles.

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package crunchify . java . tutorials ;
 
import java . io . IOException ;
import java . util . concurrent . TimeoutException ;
 
import com . whalin . MemCached . MemCachedClient ;
import com . whalin . MemCached . SockIOPool ;
 
import net . rubyeye . xmemcached . XMemcachedClient ;
import net . rubyeye . xmemcached . exception . MemcachedException ;
 
/**
* @author Crunchify.com
* Version: 1.2.4
* Details: Use dependency com.whalin.Memcached-Java-Client and com.googlecode.xmemcached to retrieve, store Key Value pair
*         from MemCached Server
*/
 
public class CrunchifyComWhalinXMemcachedClient {
public static void main ( String [ ] args ) {
 
log ( "===================================== Approach-1: Using SpyMemcahed: https://crunchify.com/memcached-java-client-net-spy-spymemcached/ ===================================== \n" ) ;
 
log ( "===================================== Approach-2: Using com.whalin.Memcached-Java-Client =====================================\n" ) ;
implementWhalinMemcachedJavaClient ( ) ;
 
log ( "===================================== Approach-3: Using com.googlecode.xmemcached Method =====================================\n" ) ;
implementXMemCachedClient ( ) ;
 
log ( "===================================== Program Completed ===================================== \n" ) ;
 
}
 
// Approach-1: Using SpyMemcahed: https://crunchify.com/memcached-java-client-net-spy-spymemcached/
 
// Approach-2: Using com.whalin.Memcached-Java-Client
private static void implementWhalinMemcachedJavaClient ( ) {
String [ ] servers = { "localhost:11211" } ;
 
// This class is a connection pool for maintaning a pool of persistent connections to memcached servers.
// The pool must be initialized prior to use. This should typically be early on in the lifecycle of the JVM instance.
SockIOPool crunchfiyPool = SockIOPool . getInstance ( "Crunchify" ) ;
 
// Sets the minimum number of spare connections to maintain in our available pool.
crunchfiyPool . setMinConn ( 2 ) ;
 
// Sets the maximum number of spare connections allowed in our available pool.
crunchfiyPool . setMaxConn ( 20 ) ;
 
// Sets the list of all cache servers.
crunchfiyPool . setServers ( servers ) ;
 
// Sets the failover flag for the pool. If this flag is set to true, and a socket fails to connect, the pool will attempt to return a socket from
// another server if one exists.
// If set to false, then getting a socket will return null if it fails to connect to the requested server.
crunchfiyPool . setFailover ( true ) ;
 
// Sets the initial number of connections per server in the available pool.
crunchfiyPool . setInitConn ( 30 ) ;
 
// Set the sleep time between runs of the pool maintenance thread. If set to 0, then the maint thread will not be started.
crunchfiyPool . setMaintSleep ( 90 ) ;
 
// Sets the socket timeout for reads.
crunchfiyPool . setSocketTO ( 2000 ) ;
 
// Sets the aliveCheck flag for the pool. When true, this will attempt to talk to the server on every connection checkout to make sure the connection is
// still valid.
crunchfiyPool . setAliveCheck ( true ) ;
 
crunchfiyPool . initialize ( ) ;
 
// Creates a new instance of MemCachedClient accepting a passed in pool name.
MemCachedClient crunchifyWhalinClient = new MemCachedClient ( "Crunchify" ) ;
 
// Adds data to the server; only the key and the value are specified.
crunchifyWhalinClient . add ( "Java" , "Crunchify.com" ) ;
crunchifyWhalinClient . add ( "WordPress" , "WordPress.com" ) ;
crunchifyWhalinClient . add ( "Social" , "Facebook.com" ) ;
 
log ( "==> Total 3 Records added to MemCached using com.whalin.Memcached-Java-Client Method\n" ) ;
 
// Retrieve a key from the server, using a specific hash.
// If the data was compressed or serialized when compressed, it will automatically be decompressed or serialized, as appropriate..
log ( "Key: Java, Value: " + crunchifyWhalinClient . get ( "Java" ) ) ;
log ( "Key: WordPress, Value: " + crunchifyWhalinClient . get ( "WordPress" ) ) ;
log ( "Key: Social, Value: " + crunchifyWhalinClient . get ( "Social" ) ) ;
 
log ( "==> Total 3 Records Retrieved from MemCached using com.whalin.Memcached-Java-Client Method\n" ) ;
 
// Deletes an object from cache given cache key.
crunchifyWhalinClient . delete ( "Social" ) ;
log ( "==> Record deleted using com.whalin.Memcached-Java-Client Method\n" ) ;
 
log ( "Key: Social, Value: " + crunchifyWhalinClient . get ( "Social" ) ) ;
log ( "==> Failure to get record Social as we deleted that before\n" ) ;
 
}
 
// Approach-3: Using com.googlecode.xmemcached
private static void implementXMemCachedClient ( ) {
String city = "New York" ;
String city2 = "San Francisco" ;
try {
 
// XMemcached constructor,default weight is 1
XMemcachedClient xMemCachedclient = new XMemcachedClient ( "localhost" , 11211 ) ;
 
// Set a value
xMemCachedclient . set ( "Crunchify" , 3600 , city ) ;
xMemCachedclient . set ( "Twitter" , 3600 , city2 ) ;
 
// Get a value for specify key
Object myCity = xMemCachedclient . get ( "Twitter" ) ;
log ( "=====> Key: Twitter, Value: " + xMemCachedclient . get ( "Twitter" ) + "\n" ) ;
 
// Get a value for specify key (set timeout of three seconds)
myCity = xMemCachedclient . get ( "Crunchify" , 3000 ) ;
log ( "=====> Key: Crunchify, Value: " + xMemCachedclient . get ( "Crunchify" , 3000 ) + "\n" ) ;
 
// Set a new expiration time for an existing item,using default opTimeout second.
xMemCachedclient . touch ( "key" , 30 ) ;
 
xMemCachedclient . delete ( "Crunchify" ) ;
log ( "=====> Key: Crunchify, Value: " + xMemCachedclient . get ( "Crunchify" ) + "\n" ) ;
 
// delete value
xMemCachedclient . delete ( "key" ) ;
 
// let's catch all exceptions
} catch ( IOException e ) {
e . printStackTrace ( ) ;
} catch ( MemcachedException e ) {
e . printStackTrace ( ) ;
} catch ( TimeoutException e ) {
e . printStackTrace ( ) ;
} catch ( InterruptedException e ) {
e . printStackTrace ( ) ;
}
}
 
// Simple log utility
private static void log ( Object object ) {
System . out . println ( object ) ;
 
}
 
}

Asegúrese de tener el servidor Memcached en funcionamiento.

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bash - 3.2 $ memcached - d - p 11211

Simplemente ejecute el comando anterior en Eclipse para ver el resultado a continuación.

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===================================== Approach - 1 : Using SpyMemcahed : https : //crunchify.com/memcached-java-client-net-spy-spymemcached/ =====================================
 
===================================== Approach - 2 : Using com . whalin . Memcached - Java - Client =====================================
 
SLF4J : The requested version 1.7.16 by your slf4j binding is not compatible with [ 1.6 ]
SLF4J : See http : //www.slf4j.org/codes.html#version_mismatch for further details.
== > Total 3 Records added to MemCached using com . whalin . Memcached - Java - Client Method
 
Key : Java , Value : Crunchify . com
Key : WordPress , Value : WordPress . com
Key : Social , Value : Facebook . com
== > Total 3 Records Retrieved from MemCached using com . whalin . Memcached - Java - Client Method
 
18 : 27 : 35.433 [ main ] DEBUG com . whalin . MemCached . MemCachedClient - ++++ deletion of key : Social from cache was a success
== > Record deleted using com . whalin . Memcached - Java - Client Method
 
Key : Social , Value : null
== > Failure to get record Social as we deleted that before
 
===================================== Approach - 3 : Using com . googlecode . xmemcached Method =====================================
 
18 : 27 : 35.456 [ main ] INFO net . rubyeye . xmemcached . XMemcachedClient - XMemcachedClient is using Text protocol
18 : 27 : 35.491 [ main ] INFO com . google . code . yanf4j . nio . impl . SelectorManager - Creating 8 reactors . . .
18 : 27 : 35.496 [ main ] INFO com . google . code . yanf4j . core . impl . AbstractController - The Controller started at localhost / 127.0.0.1 : 0 . . .
18 : 27 : 35.509 [ Xmemcached - Reactor - 0 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - session started
18 : 27 : 35.510 [ Xmemcached - Reactor - 0 ] INFO com . google . code . yanf4j . core . impl . AbstractController - Add a session : 127.0.0.1 : 11211
18 : 27 : 35.513 [ main ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - After encodingset Crunchify 0 3600 8
New York
 
18 : 27 : 35.514 [ Xmemcached - Reactor - 2 ] DEBUG net . rubyeye . xmemcached . impl . Optimizer - Optimieze merge buffer : set Crunchify 0 3600 8
New York
 
18 : 27 : 35.514 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - send buffers :
[
buffer : position = 0 , limit = 34 , capacity = 34
]
18 : 27 : 35.515 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - read 8 bytes from channel
18 : 27 : 35.515 [ main ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - After encodingset Twitter 0 3600 13
San Francisco
 
18 : 27 : 35.515 [ Xmemcached - Reactor - 2 ] DEBUG net . rubyeye . xmemcached . impl . Optimizer - Optimieze merge buffer : set Twitter 0 3600 13
San Francisco
 
18 : 27 : 35.515 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - send buffers :
[
buffer : position = 0 , limit = 38 , capacity = 38
]
18 : 27 : 35.515 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - read 8 bytes from channel
18 : 27 : 35.516 [ main ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - After encodingget Twitter
 
18 : 27 : 35.517 [ Xmemcached - Reactor - 2 ] DEBUG net . rubyeye . xmemcached . impl . Optimizer - Optimieze merge buffer : get Twitter
 
18 : 27 : 35.517 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - send buffers :
[
buffer : position = 0 , limit = 13 , capacity = 13
]
18 : 27 : 35.518 [ main ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - After encodingget Twitter
 
18 : 27 : 35.518 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - read 40 bytes from channel
18 : 27 : 35.518 [ Xmemcached - Reactor - 2 ] DEBUG net . rubyeye . xmemcached . impl . Optimizer - Optimieze merge buffer : get Twitter
 
18 : 27 : 35.518 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - send buffers :
[
buffer : position = 0 , limit = 13 , capacity = 13
]
===== > Key : Twitter , Value : San Francisco
 
18 : 27 : 35.518 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - read 40 bytes from channel
18 : 27 : 35.519 [ main ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - After encodingget Crunchify
 
18 : 27 : 35.519 [ Xmemcached - Reactor - 2 ] DEBUG net . rubyeye . xmemcached . impl . Optimizer - Optimieze merge buffer : get Crunchify
 
18 : 27 : 35.519 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - send buffers :
[
buffer : position = 0 , limit = 15 , capacity = 15
]
18 : 27 : 35.519 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - read 36 bytes from channel
18 : 27 : 35.519 [ main ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - After encodingget Crunchify
 
18 : 27 : 35.519 [ Xmemcached - Reactor - 2 ] DEBUG net . rubyeye . xmemcached . impl . Optimizer - Optimieze merge buffer : get Crunchify
 
18 : 27 : 35.519 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - send buffers :
[
buffer : position = 0 , limit = 15 , capacity = 15
]
===== > Key : Crunchify , Value : New York
 
18 : 27 : 35.520 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - read 36 bytes from channel
18 : 27 : 35.520 [ main ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - After encodingtouch key 30
 
18 : 27 : 35.520 [ Xmemcached - Reactor - 2 ] DEBUG net . rubyeye . xmemcached . impl . Optimizer - Optimieze merge buffer : touch key 30
 
18 : 27 : 35.520 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - send buffers :
[
buffer : position = 0 , limit = 14 , capacity = 14
]
18 : 27 : 35.520 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - read 11 bytes from channel
18 : 27 : 35.520 [ main ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - After encodingdelete Crunchify
 
18 : 27 : 35.520 [ Xmemcached - Reactor - 2 ] DEBUG net . rubyeye . xmemcached . impl . Optimizer - Optimieze merge buffer : delete Crunchify
 
18 : 27 : 35.521 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - send buffers :
[
buffer : position = 0 , limit = 18 , capacity = 18
]
18 : 27 : 35.521 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - read 9 bytes from channel
18 : 27 : 35.521 [ main ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - After encodingget Crunchify
 
18 : 27 : 35.521 [ Xmemcached - Reactor - 2 ] DEBUG net . rubyeye . xmemcached . impl . Optimizer - Optimieze merge buffer : get Crunchify
 
18 : 27 : 35.521 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - send buffers :
[
buffer : position = 0 , limit = 15 , capacity = 15
]
===== > Key : Crunchify , Value : null
 
18 : 27 : 35.521 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - read 5 bytes from channel
18 : 27 : 35.521 [ main ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - After encodingdelete key
 
18 : 27 : 35.521 [ Xmemcached - Reactor - 2 ] DEBUG net . rubyeye . xmemcached . impl . Optimizer - Optimieze merge buffer : delete key
 
18 : 27 : 35.521 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - send buffers :
[
buffer : position = 0 , limit = 12 , capacity = 12
]
===================================== Program Completed =====================================
 
18 : 27 : 35.522 [ Xmemcached - Reactor - 2 ] DEBUG com . google . code . yanf4j . core . impl . AbstractSession - read 11 bytes from channel

Como puede ver en el resultado anterior, es fácil recuperar y guardar valor y es la forma más rápida de tener una solución de almacenamiento en caché central para su aplicación Java de producción.