Ehcache提供了基于JMX的监控支持，支持对以下几类信息的监控。
- CacheManager
- Cache
- CacheConfiguration
- CacheStatistics
按照JMX的规范，为了支持对这几类信息的监控支持，Ehcache分别为它们建立了对应的MBean接口，这些接口都定义在net.sf.ehcache.management包中，分别是CacheManagerMBean、CacheMBean、CacheConfigurationMBean和CacheStatisticsMBean。按照JMX的规范，JMX监控页面只能查看MBean中定义的属性（get方法）和执行MBean接口中定义的操作（方法）。比方说CacheManagerMBean的定义如下，它能看到的属性就是status、name、cacheNames、caches、transactionCommittedCount、transactionRolledBackCount和transactionTimedOutCount。能进行的操作是shutdown()和clearAll()。
public interface CacheManagerMBean {
/**
* Gets the status attribute of the Ehcache
*
* @return The status value, as a String from the Status enum class
*/
String getStatus();
/**
* Gets the name of the cache manager
*
* @return The name of the CacheManager
*/
String getName();
/**
* Shuts down the CacheManager.
* <p/>
* If the shutdown occurs on the singleton, then the singleton is removed, so that if a singleton access method
* is called, a new singleton will be created.
*/
void shutdown();
/**
* Clears the contents of all caches in the CacheManager, but without
* removing any caches.
* <p/>
* This method is not synchronized. It only guarantees to clear those elements in a cache
* at the time that the {@link net.sf.ehcache.Ehcache#removeAll()} mehod on each cache is called.
*/
void clearAll();
/**
* Returns a JMX Cache bean
*
*/
Cache getCache(String name);
/**
* Gets the cache names managed by the CacheManager
*/
String[] getCacheNames() throws IllegalStateException;
/**
* Gets a list of caches in this CacheManager
* @return a list of JMX Cache objects
*/
List getCaches();
/**
* Get the committed transactions count
* @return the committed transactions count
*/
long getTransactionCommittedCount();
/**
* Get the rolled back transactions count
* @return the rolled back transactions count
*/
long getTransactionRolledBackCount();
/**
* Get the timed out transactions count. Note that only transactions which failed to
* commit due to a timeout are taken into account
* @return the timed out transactions count
*/
long getTransactionTimedOutCount();
}注册这些MBean，Ehcache提供了一个工具类，ManagementService，可以通过它的registerMBeans方法进行注册，该方法定义如下，后面对应的4个boolean类型的参数，表示是否需要注册对应的MBean，依次表示CacheManager、Cache、CacheConfiguration和CacheStatistics。该工具方法最终会生成一个ManagementService实例，ManagementService实现了CacheManagerEventListener接口，所以它能感知到Cache的变化。
public static void registerMBeans(
net.sf.ehcache.CacheManager cacheManager,
MBeanServer mBeanServer,
boolean registerCacheManager,
boolean registerCaches,
boolean registerCacheConfigurations,
boolean registerCacheStatistics) throws CacheException {
//...
}
以下是一个注册Ehcache对应的MBean的示例代码：
CacheManager cacheManager = new CacheManager();
String cacheName = "test";
Ehcache cache = cacheManager.addCacheIfAbsent(cacheName);
cache.put(new Element("key is a object", "value is a object")); MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer();
ManagementService.registerMBeans(cacheManager, mBeanServer, true, true, true, true);
注册之后我们就可以通过jconsole的JMX界面看到对应的MBean的信息了。
Ehcache相关的MBean的objectName的命名规范如下：
- CacheManager -
“net.sf.ehcache:type=CacheManager,name=<CacheManager>” - Cache -
“net.sf.ehcache:type=Cache,CacheManager=<cacheManagerName>,name=<cacheName>” - CacheConfiguration -
“net.sf.ehcache:type=CacheConfiguration,CacheManager=<cacheManagerName>,name=<cacheName>” - CacheStatistics -
“net.sf.ehcache:type=CacheStatistics,CacheManager=<cacheManagerName>,name=<cacheName>”
参考文档 http://www.ehcache.org/documentation/2.7/operations/jmx.html
（本文是基于Ehcache2.10.4所写，由Elim写于2017年10月8日）