package net.sf.appstatus.support.spring.cache;
   
   import java.util.Collection;
   import java.util.concurrent.ConcurrentHashMap;
   import java.util.concurrent.ConcurrentMap;
   
   import org.springframework.cache.Cache;
   import org.springframework.cache.CacheManager;
   
  /**
   * This is an adapter for Spring cache manager which wraps returned cache
   * instances.
   * 
   * <p>
   * When the cache returns a value and AppStatus is used with useThreadLocal and
   * a service call is active (IServiceMonitor#beginCall was called), the current
   * service call is flagged as "cacheHit".
   * 
   * <p>
   * Usage : simply add AppStatusCacheManager as your cacheManager and reference
   * your previous spring cache manager in your Spring config files.
   * <p>
   * With EhCacheManager :
   * 
   * <pre>
   * &lt;bean id="cacheManager" class="net.sf.appstatus.support.spring.cache.AppStatusCacheManager" p:cache-manager-ref="ehCacheCacheManager"/>
   * 
   * 
   * &lt;bean id="ehCacheCacheManager" class="org.springframework.cache.ehcache.EhCacheCacheManager" p:cache-manager-ref="ehcache"/>
   * 
   * &lt;!-- Ehcache library setup -->
   * &lt;bean id="ehcache" class="org.springframework.cache.ehcache.EhCacheManagerFactoryBean" p:config-location="ehcache.xml"/>
   * </pre>
   * 
   * 
   * @author Nicolas Richeton
   * 
   */
  public class AppStatusCacheManager implements CacheManager {
  	private CacheManager cacheManager;
  
  	private final ConcurrentMap<String, AppStatusCacheAdapter> cacheMap = new ConcurrentHashMap<String, AppStatusCacheAdapter>(
  			16);
  
  	public AppStatusCacheManager() {
  	}
  
  	public Cache getCache(String name) {
  		Cache cache = cacheManager.getCache(name);
  		if(cache == null){
  			return null;
  		}
  		AppStatusCacheAdapter result = cacheMap.get(cache.getName());
  
  		if (result == null) {
  			result = new AppStatusCacheAdapter(cache);
  			cacheMap.put(cache.getName(), result);
  		}
  
  		return result;
  	}
  
  	public Collection<String> getCacheNames() {
  		return cacheManager.getCacheNames();
  	}
  
  	public void setCacheManager(CacheManager cacheManager) {
  		this.cacheManager = cacheManager;
  	}
  }