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Implementing @ApacheIgnite's cache store (part II)

Apache Ignite’s CacheStore interface is an API for cache persistence storage for read-through and write-through behavior.  When implementing this interface, you choose the type of key and value object alike -- similar to a map.  This follows the pattern established by the CacheLoader and CacheWriter interfaces CacheStore extends of the JSR107 specification.  In many cases, having a specific implementation for each method when implementing this interface may not be necessary, so Apache Ignite has a CacheStoreAdapter for this purpose.

Since Caches so closely resemble Maps, perhaps we should begin our discussion with a cache implementation that is essentially a HashMap store:

public class HashMapStore extends CloudStoreAdapter {

private final Map<Object, Object> map = new HashMap<>();

@Override public void loadCache(IgniteBiInClosure c, Object … args) {

for(Map.Entry e : map.entrySet()) {
c.apply(e.getKey(), e.getValues());

@Override public Object load(Object key) {
Return map.get(key);

@Override public void write(Cache.Entry e) {
map.put(e.getKey(), e.getValue());

@Override public void delete(Object key) {

To use an Ignite cache, a configuration must be provided.  This can be done several ways -- including declaratively using a Spring XML configuration or programmatically using Ignite’s native CacheConfiguration object.

    Ignite’s CacheConfiguration class extends the MutableConfiguration class of the JSR107 specification.  When configuring an Ignite cache, out of the dozens of settings to choose from there are some settings that are at least as important as setting the name of the cache.  One of these settings is the write synchronization mode.  Each mode setting indicates how ignite should wait for write replies from other nodes.  The three possible settings as provided by the CacheWriteSynchronizationMode enum are FULL_SYNC, FULL_ASYNC, and PRIMARY_SYNC.  The standard setting is FULL_SYNC.  This setting guarantees that whenever any of the atomic or transactional writes complete, all other participating nodes which cache the written data has been updated.


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