Custom read-though loader is now working using the JCache get

[liuxiaodu]

We have tried to use Infinispan implementation and leverage the standard JSR107 JCache to reference the cache in the code.  We run into the issue when we configured the read-through custom loader and using the get on the JCache object, the load function of the custom loader did not get called.  However, if we unwrap the JCache to infinispan Cache and call the get on this object, the load function of the custom loader did get called.

We would like to know if it is possible to configure the infinispan custom loader and using JCache to allow the custom loader work the achieve the read-through or self-populating on the cache instance.

Thanks a lot.

Louie

[william.burns]

JCache Configuration by default disables read through.  You need to explicitly enable this through the configuration.

// Retrieve the system wide cache manager
CacheManager cacheManager = Caching.getCachingProvider().getCacheManager();
// Define a named cache with default JCache configuration
Cache<String, String> cache = cacheManager.createCache("namedCache",
  new MutableConfiguration<String, String>().setReadThrough(true));

[liuxiaodu]

Thanks for your help. 

Regarding the configuration, we prefer the using configuration file.  For example, here is one of our configuration file:

<?xml version="1.0" encoding="UTF-8"?>

<infinispan xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

  xsi:schemaLocation="urn:infinispan:config:7.0 http://www.infinispan.org/schemas/infinispan-config-7.0.xsd"

  xmlns="urn:infinispan:config:7.0">

  <jgroups>

    <stack-file name="tcp" path="${catalina.base}/conf/tcp-nio.xml" />

  </jgroups>

  <cache-container default-cache="default">

    <transport cluster="jcache-cluster" stack="tcp" node-name="${nodeName}" />

    <replicated-cache name="repl" mode="SYNC" >

      <persistence passivation="false">

        <file-store

          shared="false"

          preload="true"

          fetch-state="true"

          read-only="false"

          purge="false"

          path="${catalina.base}/temp/infinispan">

          <write-behind flush-lock-timeout="15000" thread-pool-size="5" /> 

        </file-store>

        <store class="org.jboss.infinispan.jcache.ReplCustomLoader"

          shared="false"

          preload="false"

          fetch-state="false"

          read-only="true"

          purge="false"

          singleton="false"

        />

      </persistence>

      <transaction mode="BATCH" />

    </replicated-cache>

  </cache-container>

</infinispan>

We use the following method to configure and retrieve the JCache instance:

javax.cache.CacheManager jCacheManager = Caching.getCachingProvider().getCacheManager(configurationFile.toURI(), Thread.currentThread().getContextClassLoader());

javax.cache.Cache<String, String> cache = this.jCacheManager.getCache(cacheName);

We would like to know if it is possible to set this isReadThrough in the above configuration file instead of in the code.  We prefer using configuration since we can share the same cache manager and change the configuration to allow server configuration do have loader configured and client do not have the loader configured.

Thanks again.

[galder.zamarreno]

Hi Louie, there might a way to do what you suggest. Essentially, you'd need to create caches via "createCache(String cacheName, C configuration)", and in the configuration, pass your own subclass of javax.cache.configuration.CompleteConfiguration. This subclass would be created with Infinispan XML configuration as parsed (e.g. created the cache manager and get a cache's configuration would do), and then in isReadThrough implementation, you could check for example if the Infinispan XML configuration has a persistence store, and if so enable isReadThrough. You could also do this if you subclass MutableConfiguration, but there's a problem with MutableConfiguration which is the fact that you don't know when isReadThrough is false, whether that's because it's default value or because someone called setReadThrough specifically. If you provide your own implementation javax.cache.configuration.CompleteConfiguration, you can initialise isReadThrough instance variable as null, and null serves you as a way to know that the user has not explicitly called setReadThrough.

[liuxiaodu]

Than you all for the help.  I found the solution by cast the configuration to MutableConfiguration  and set the flag.  Here is the steps:

javax.cache.CacheManager jCacheManager = Caching.getCachingProvider().getCacheManager(configurationFile.toURI(), Thread.currentThread().getContextClassLoader());

javax.cache.Cache<String, String> cache = this.jCacheManager.getCache(cacheName);

final MutableConfiguration<String, String> cfg = cache.getConfiguration(MutableConfiguration.class);\

cache.get(key);  //read-through works know.

Louie