Tomcat的ResourceCache有什么作用？ hitsCount和accessCount有什么区别？

Question

I am trying to monitor tomcat with the MBeanUtil class,I came accross the ResourceCache and its statistics.

what exactly does a resourcecache do?

I found few stats related to the Cache 1)hitsCount 2)accessCount 3) cacheSize

What does each of the above stats specify.

Answer 1

The documentation states that ResourceCache implements a special purpose cache. As its name implies it is used for caching resources that are looked up through JNDI.

From the sources I see that accessCount is incremented every time a look up is performed. hitsCount is incremented every time a resource object is returned (it is not incremented when the resource isn't found). cacheSize is the size of the cache in KB.