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| <html> |
| <body> |
| <h2>Memcache EntityStore CachePool.</h2> |
| <p>Memcache has no namespace support. In addition to that, the protocol disallow key listing.</p> |
| <p>The CachePool contract is to drop a cache once all of its references have been returned.</p> |
| <p>Therefore, all keys are prefixed, that way;</p> |
| <pre>cacheId.cacheInstanceId.key</pre> |
| <ul> |
| <li><code>cacheId</code> is the identity of the requested cache</li> |
| <li><code>cacheInstanceId</code> is an autogenerated cache instance identifier</li> |
| <li><code>key</code> is the original key</li> |
| </ul> |
| <p> |
| In other words and for a given <code>cacheId</code>, once all references of the Cache are returned to the |
| CachePool, the next <code>fetchCache(..)</code> invocation will generate a new Cache instance identifier and |
| hence use different prefixed keys. |
| </p> |
| <p> |
| All this allow the Memcache EntityStore CachePool to conform to the CachePool contract despite limitations |
| of the Memcache protocol. |
| </p> |
| </body> |
| </html> |
