package ch.qos.logback.core.joran.util.beans;
   
   import java.util.HashMap;
   import java.util.Map;
   
   import ch.qos.logback.core.Context;
   import ch.qos.logback.core.spi.ContextAwareBase;
   
   /**
   *
   * Cache for {@link BeanDescription} instances. All the cache users which use
   * the same instance of BeanDescriptionCache can profit from each others cached
   * bean descriptions.
   * 
   * <p>
   * The cache is not thread-safe and should not be shared across configurator
   * instances.
   *
   * @author urechm
   *
   */
  public class BeanDescriptionCache extends ContextAwareBase {
  
      private Map<Class<?>, BeanDescription> classToBeanDescription = new HashMap<Class<?>, BeanDescription>();
      private BeanDescriptionFactory beanDescriptionFactory;
  
      public BeanDescriptionCache(Context context) {
          setContext(context);
      }
  
      private BeanDescriptionFactory getBeanDescriptionFactory() {
          if (beanDescriptionFactory == null) {
              beanDescriptionFactory = new BeanDescriptionFactory(getContext());
          }
          return beanDescriptionFactory;
      }
  
      /**
       * Returned bean descriptions are hold in a cache. If the cache does not contain
       * a description for a given class, a new bean description is created and put in
       * the cache, before it is returned.
       *
       * @param clazz to get a bean description for.
       * @return a bean description for the given class.
       */
      public BeanDescription getBeanDescription(Class<?> clazz) {
          if (!classToBeanDescription.containsKey(clazz)) {
              BeanDescription beanDescription = getBeanDescriptionFactory().create(clazz);
              classToBeanDescription.put(clazz, beanDescription);
          }
          return classToBeanDescription.get(clazz);
      }
  
  }