我看了下WebContextFactory的源代码如下: public class WebContextFactory { /** * Accessor for the current WebContext. * @return The current WebContext or null if the current thread was not * started by DWR. */ public static WebContext get() { if (builder == null) { return null; } return builder.get(); } /** * Internal method to allow us to get the WebContextBuilder from which we * will get WebContext objects. * Do not call this method from outside of DWR. * @param builder The factory object (from DwrServlet) */ public static void setWebContextBuilder(WebContextBuilder builder) { WebContextFactory.builder = builder; } /** * The WebContextBuilder from which we will get WebContext objects */ private static WebContextBuilder builder; /** * Class to enable us to access servlet parameters. */ public interface WebContextBuilder { /** * Make the current thread know what the current request is. * This method is only for use internally to DWR. * @param request The incoming http request * @param response The outgoing http reply * @param config The servlet configuration * @param context The servlet context * @param container The IoC container * @see #unset() */ void set(HttpServletRequest request, HttpServletResponse response, ServletConfig config, ServletContext context, Container container); /** * @return The WebContext that is associated with this thread */ WebContext get(); /** * Unset the current ExecutionContext * This method is only for use internally to DWR. * @see #set(HttpServletRequest, HttpServletResponse, ServletConfig, ServletContext, Container) */ void unset(); } }
public class WebContextFactory
{
/**
* Accessor for the current WebContext.
* @return The current WebContext or null if the current thread was not
* started by DWR.
*/
public static WebContext get()
{
if (builder == null)
{
return null;
} return builder.get();
} /**
* Internal method to allow us to get the WebContextBuilder from which we
* will get WebContext objects.
* Do not call this method from outside of DWR.
* @param builder The factory object (from DwrServlet)
*/
public static void setWebContextBuilder(WebContextBuilder builder)
{
WebContextFactory.builder = builder;
} /**
* The WebContextBuilder from which we will get WebContext objects
*/
private static WebContextBuilder builder; /**
* Class to enable us to access servlet parameters.
*/
public interface WebContextBuilder
{
/**
* Make the current thread know what the current request is.
* This method is only for use internally to DWR.
* @param request The incoming http request
* @param response The outgoing http reply
* @param config The servlet configuration
* @param context The servlet context
* @param container The IoC container
* @see #unset()
*/
void set(HttpServletRequest request, HttpServletResponse response, ServletConfig config, ServletContext context, Container container); /**
* @return The WebContext that is associated with this thread
*/
WebContext get(); /**
* Unset the current ExecutionContext
* This method is only for use internally to DWR.
* @see #set(HttpServletRequest, HttpServletResponse, ServletConfig, ServletContext, Container)
*/
void unset();
}
}