In Java Come implementare il client Memcached utilizzando la libreria net.spy.spymemcached?
Pubblicato: 2020-12-27
Pochi giorni fa ho scritto un articolo su come configurare e avviare MemCached Server in locale su Mac OS con pochi semplici passaggi.
Esistono tre modi diversi per creare il client Java Memcached.
- metodo net.spy.spymemcached
- com.whalin.Memcached – Java – Metodo client
- com.googlecode.xmemcached
In questo tutorial esamineremo come scrivere un semplice client Java utilizzando la libreria net.spy.spymemcached . Se hai Maven Project nel tuo ambiente Eclipse, aggiungi sotto la dipendenza al file pom.xml .
Dai un'occhiata alle operazioni set(), get(), delete().
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< dependency > < groupId > net . spy < / groupId > < artifactId > spymemcached < / artifactId > < version > 2.12.3 < / version > < / dependency > |
Dopo aver aggiornato il tuo file pom.xml, prova ad aggiornare il tuo progetto Java. La prossima cosa è scrivere un semplice programma Java.
implementareSpyMemcached.java
La libreria viene fornita con operazioni set() , get() , delete() molto semplici. Ecco un esempio completo.
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package crunchify . java . tutorials ; import net . spy . memcached . MemcachedClient ; import java . io . IOException ; import java . net . InetSocketAddress ; /** * @author Crunchify.com * Version: 1.0.0 * Details: Use dependency net.spy.spymemcached to retrieve, store Key Value pair from MemCached Server * */ public class CrunchifySpyMemcachedClient { public static void main ( String [ ] args ) { implementCrunchifySpyMemcached ( ) ; } // Approach-1: net.spy.spymemcached // Use dependency net.spy.spymemcached to retrieve, store Key Value pair from MemCached Server private static void implementCrunchifySpyMemcached ( ) { // Get a memcache client operating on the specified memcached locations. MemcachedClient crunchifySpyMemCached ; try { crunchifySpyMemCached = new MemcachedClient ( new InetSocketAddress ( "127.0.0.1" , 11211 ) ) ; log ( "=====> Approach-1: SpyMemcached <=====\n" ) ; log ( "==> Connected to Crunchify's Local Server Successfully." + " Host: localhost, Port: 11211" ) ; // Set an object in the cache (using the default transcoder) regardless of any existing value. // The exp value is passed along to memcached exactly as given, and will be processed per the memcached protocol specification: // The actual value sent may either be Unix time (number of seconds since January 1, 1970, as a 32-bit value), or a number of seconds starting from // current time. In the latter case, this number of seconds may not exceed 60*60*24*30 (number of seconds in 30 days); if the number sent by a // client is larger than that, the server will consider it to be real Unix time value rather than an offset from current time. crunchifySpyMemCached . set ( "Crunchify" , 2000 , "New York" ) ; crunchifySpyMemCached . set ( "Google" , 2000 , "Mountain View" ) ; crunchifySpyMemCached . set ( "PayPal" , 2000 , "San Jose" ) ; crunchifySpyMemCached . set ( "Twitter" , 2000 , "San Francisco" ) ; crunchifySpyMemCached . set ( "Amazon" , 2000 , "Seattle" ) ; log ( "==> Total 5 Records added to MemCached using net.spy.spymemcached method\n" ) ; // Get with a single key and decode using the default transcoder. log ( "Key: Google, Value: " + crunchifySpyMemCached . get ( "Google" ) ) ; log ( "Key: PayPal, Value: " + crunchifySpyMemCached . get ( "PayPal" ) ) ; log ( "Key: Twitter, Value: " + crunchifySpyMemCached . get ( "Twitter" ) ) ; log ( "Key: Amazon, Value: " + crunchifySpyMemCached . get ( "Amazon" ) ) ; log ( "Key: Crunchify, Value: " + crunchifySpyMemCached . get ( "Crunchify" ) ) ; log ( "==> Total 5 Records Retrieved from MemCached using net.spy.spymemcached method\n" ) ; // Delete the given key from the cache. crunchifySpyMemCached . delete ( "Crunchify" ) ; log ( "==> Key:Crunchify deleted successfully\n" ) ; log ( "Key: Crunchify, Value: " + crunchifySpyMemCached . get ( "Crunchify" ) ) ; log ( "==> If no record found, it returns NULL\n" ) ; } catch ( IOException e ) { // Prints this throwable and its backtrace to the standard error stream e . printStackTrace ( ) ; } } private static void log ( Object object ) { System . out . println ( object ) ; } } |
Avvia MemCached Server in locale
Vai alla finestra Terminale e digita command memcached -d -p 11211 .
Tutorial: come installare e configurare Memcached Process/Server su Mac OS X?
Uscita console Eclipse:
Basta eseguire sopra il programma un'applicazione Java e dovresti vedere un risultato come questo.
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2018 - 12 - 07 16 : 25 : 45.437 INFO net . spy . memcached . MemcachedConnection : Setting retryQueueSize to - 1 2018 - 12 - 07 16 : 25 : 45.459 INFO net . spy . memcached . MemcachedConnection : Added { QA sa =/ 127.0.0.1 : 11211 , #Rops=0, #Wops=0, #iq=0, topRop=null, topWop=null, toWrite=0, interested=0} to connect queue ===== > Approach - 1 : SpyMemcached < ===== == > Connected to Crunchify ' s Local Server Sucessfully . Host : localhost , Port : 11211 == > Total 5 Records added to MemCached using net . spy . spymemcached method Key : Google , Value : Mountain View Key : PayPal , Value : San Jose Key : Twitter , Value : San Francisco Key : Amazon , Value : Seattle Key : Crunchify , Value : New York == > Total 5 Records Retrieved from MemCached using net . spy . spymemcached method == > Key : Crunchify deleted successfully Key : Crunchify , Value : null == > If no record found , it returns NULL |
Fammi sapere se riscontri problemi durante l'esecuzione del programma. Nel prossimo tutorial we will go over another libraries per impostare e ottenere i dati Memcached.
E dopo?
Prova Memcached Java Client Tutorial con altre due librerie.