Red Hat Summit Red Hat SummitSupportConsoleDéveloppeursCommencer un essaiContact

Ce contenu n'est pas disponible dans la langue sélectionnée.

10.2. Use the Default Cache

10.2.1. Add and Remove Data from the Cache
Copier lien

Red Hat JBoss Data Grid offers an interface that is similar to the proposed JSR-107 API to access and alter data stored in a cache.
The following procedure is an example that defines what each line entered into the DefaultCacheQuickstart.java file does:

Procedure 10.2. Add and Remove Data from the Cache

  1. Add an entry, replacing key and value with the desired key and value: 
    cache.put("key", "value");
    Copy to Clipboard Toggle word wrap
  2. Confirm that the entry is present in the cache: 
    assertEquals(1, cache.size());
assertTrue(cache.containsKey("key"));
    Copy to Clipboard Toggle word wrap
  3. Remove the entry from the cache: 
    Object v = cache.remove("key");
    Copy to Clipboard Toggle word wrap
  4. Confirm that the entry is no longer present in the cache: 
    assertEquals("value", v);
assertTrue(cache.isEmpty());
    Copy to Clipboard Toggle word wrap
Report a bug

10.2.2. Adding and Replacing a Key Value
Copier lien

Red Hat JBoss Data Grid offers a thread-safe data structure.
The following procedure is an example that defines what each line entered into the DefaultCacheQuickstart.java file does:

Procedure 10.3. Adding and Replacing a Key Value

  • Add an entry key with value as the key's value. 
    cache.put("key", "value");
    Copy to Clipboard Toggle word wrap

Procedure 10.4. Replacing a Key Value

  1. The following code searches for keys (named key and key2). If the two specific keys beings searched for are not found, JBoss Data Grid creates two new keys with the specified key names and values. 
    cache.putIfAbsent("key", "newValue");
cache.putIfAbsent("key2", "value2");
    Copy to Clipboard Toggle word wrap
  2. The following code confirms that the value of the stored key equals the value we wanted to store. 
    assertEquals(cache.get("key"), "value");
assertEquals(cache.get("key2"), "value2");
    Copy to Clipboard Toggle word wrap

See Also:

Report a bug

10.2.3. Removing Entries
Copier lien

Separate methods are used to remove entries depending on how JBoss Data Grid is used:
Library Mode

All of the following methods are found on org.infinispan.Cache and its subclasses.

  • remove(key) - remove a single key from the cache.
  • removeAsync(key) - remove a single key from the cache, asynchronously.
  • clear() - removes all of the mappings from the cache, leaving it empty once the call completes.
  • clearAsync() - asynchronously remove all of the mappings from the cache, leaving it empty once the call completes.
  • cache.evict(key) - remove the entry from the cache, moving it to the cache store if one is defined. With no cache store defined the entry is removed from the cache and is lost.

Remote Client-Server Mode

All of the following methods are found on org.infinispan.client.hotrod.RemoteCache and its subclasses.

  • remove(key) - remove a single key from the cache.
  • removeAsync(key) - remove a single key from the cache, asynchronously.
  • clear() - removes all of the mappings from the cache, leaving it empty once the call completes.
  • clearAsync() - asynchronously remove all of the mappings from the cache, leaving it empty once the call completes.
  • removeWithVersion(key, version) - remove a single key from the cache only if its current version matches the supplied version.
  • removeWithVersionAsync(key, value) - asynchronously remove a single key from the cache only if its current version matches the supplied version.

For additional information on any of the above methods refer to the API Documentation.
Report a bug

10.2.4. Placing and Retrieving Sets of Data
Copier lien

The AdvancedCache and RemoteCache interfaces include methods to either put or get a Map of existing data in bulk. These operations are typically much more efficient than an equivalent sequence of individual operations, especially when using them in server-client mode, as a single network operation occurs as opposed to multiple transactions.
When using the bulk operations the memory overhead is higher during the operation itself, as the get or put operation must accommodate for the full Map in a single execution.
The methods for each class are found below:
  • AdvancedCache:
    • Map<K,V> getAll(Set<?> keys) - returns a Map containing the values associated with the set of keys requested.
    • void putAll(Map<? extends K, ? extends V> map, Metadata metadata) - copies all of the mappings from the specified map to this cache, which takes an instance of Metadata to provide metadata information such as the lifespan, version, etc. on the entries being stored.
  • RemoteCache:
    • Map<K,V> getAll(Set<? extends K> keys) - returns a Map containing the values associated with the set of keys requested.
    • void putAll(Map<? extends K, ? extends V> map) - copies all of the mappings from the specified map to this cache.
    • void putAll(Map<? extends K, ? extends V> map, long lifespan, TimeUnit unit) - copies all of the mappings from the specified map to this cache, along with a lifespan before the entry is expired.
    • void putAll(Map<? extends K, ? extends V> map, long lifespan, TimeUnit lifespanUnit, long maxIdleTime, TimeUnit maxIdleTimeUnit) - copies all of the mappings from the specified map to this cache, along with both a timespan before the entries are expired and the maximum amount of time the entry is allowed to be idle before it is considered to be expired.
Report a bug

10.2.5. Adjust Data Life
Copier lien

Red Hat JBoss Data Grid entries are immortal by default, but these settings can be altered.
The following procedure is an example that defines what each line entered into the DefaultCacheQuickstart.java file does:

Procedure 10.5. Adjust the Data Life

  1. Alter the key's lifespan value: 
    cache.put("key", "value", 5, TimeUnit.SECONDS);
    Copy to Clipboard Toggle word wrap
  2. Check if the cache contains the key: 
    assertTrue(cache.containsKey("key"));
    Copy to Clipboard Toggle word wrap
  3. After the allocated lifespan time has expired, the key is no longer in the cache: 
    Thread.sleep(10000);
assertFalse(cache.containsKey("key"));
    Copy to Clipboard Toggle word wrap
Report a bug

10.2.6. Default Data Mortality
Copier lien

As a default, newly created entries do not have a life span or maximum idle time value set. Without these two values, a data entry will never expire and is therefore known as immortal data.
Report a bug

10.2.7. Register the Named Cache Using XML
Copier lien

To configure the named cache declaratively (using XML) rather than programmatically, configure the infinispan.xml file.
An example infinispan.xml file is located in https://github.com/jboss-developer/jboss-jdg-quickstarts/ within the secure-embedded-cache/src/main/resources/ folder, and the full schema is available in the docs/schema/ directory of the Red Hat JBoss Data Grid Library distribution.
Report a bug
Retour au début
Red Hat logoGithubredditYoutubeTwitter

Apprendre

Essayez, achetez et vendez

Communautés

À propos de la documentation Red Hat

Nous aidons les utilisateurs de Red Hat à innover et à atteindre leurs objectifs grâce à nos produits et services avec un contenu auquel ils peuvent faire confiance. Découvrez nos récentes mises à jour.

Rendre l’open source plus inclusif

Red Hat s'engage à remplacer le langage problématique dans notre code, notre documentation et nos propriétés Web. Pour plus de détails, consultez le Blog Red Hat.

À propos de Red Hat

Nous proposons des solutions renforcées qui facilitent le travail des entreprises sur plusieurs plates-formes et environnements, du centre de données central à la périphérie du réseau.

Theme

© 2025 Red Hat