code: public synchronized void invalidate()
  	{
  		// Remove this cached wrapper from the appropriate cache
          if (invalidated != true){
  			if (com.ibm.ejs.ras.TraceComponent.isAnyTracingEnabled()&&logger.isLoggable (Level.FINE))  //306998.15
  				logger.logp(Level.FINE, CLASS_NAME,"invalidate", "first invalidate");
  			WebContainer.removeFromCache(cacheKeyStr);
  
  			/* Avoid nulling things out so we can continue to handle requests in this wrapper
  	                     * while the app is being destroyed
  			cacheTarget = null;
  			_servletPath = null;
  			_pathInfo = null;
                          webapp = null;
  			cacheKeyStr = null;
  			*/
  			invalidated = true;
  		}
  		else{
  			if (com.ibm.ejs.ras.TraceComponent.isAnyTracingEnabled()&&logger.isLoggable (Level.FINE))  //306998.15
  				logger.logp(Level.FINE, CLASS_NAME,"invalidate", "additional invalidate");
  		}
  	}
docs: @see com.ibm.ws.webcontainer.util.CacheWrapper#invalidate()
  
  Called by the ServletWrapper when it is being destroy()ed.