Package io.undertow.servlet.spec

Class AsyncContextImpl

java.lang.Object
io.undertow.servlet.spec.AsyncContextImpl
All Implemented Interfaces:
AsyncContext
public class AsyncContextImpl extends Object implements AsyncContext
Author:
Stuart Douglas

  • Constructor Details

  • Method Details

    • updateTimeout

      public void updateTimeout()

    • getRequest

      public ServletRequest getRequest()
      Description copied from interface: AsyncContext
      Gets the request that was used to initialize this AsyncContext by calling ServletRequest.startAsync() or ServletRequest.startAsync(ServletRequest, ServletResponse).
      Specified by:
      getRequest in interface AsyncContext
      Returns:
      the request that was used to initialize this AsyncContext

    • getResponse

      public ServletResponse getResponse()
      Description copied from interface: AsyncContext
      Gets the response that was used to initialize this AsyncContext by calling ServletRequest.startAsync() or ServletRequest.startAsync(ServletRequest, ServletResponse).
      Specified by:
      getResponse in interface AsyncContext
      Returns:
      the response that was used to initialize this AsyncContext

    • hasOriginalRequestAndResponse

      public boolean hasOriginalRequestAndResponse()
      Description copied from interface: AsyncContext
      Checks if this AsyncContext was initialized with the original or application-wrapped request and response objects.

      This information may be used by filters invoked in the outbound direction, after a request was put into asynchronous mode, to determine whether any request and/or response wrappers that they added during their inbound invocation need to be preserved for the duration of the asynchronous operation, or may be released.

      Specified by:
      hasOriginalRequestAndResponse in interface AsyncContext
      Returns:
      true if this AsyncContext was initialized with the original request and response objects by calling ServletRequest.startAsync(), or if it was initialized by calling ServletRequest.startAsync(ServletRequest, ServletResponse), and neither the ServletRequest nor ServletResponse arguments carried any application-provided wrappers; false otherwise

    • isInitialRequestDone

      public boolean isInitialRequestDone()

    • dispatch

      public void dispatch()
      Description copied from interface: AsyncContext
      Dispatches the request and response objects of this AsyncContext to the servlet container.

      If the asynchronous cycle was started with ServletRequest.startAsync(ServletRequest, ServletResponse), and the request passed is an instance of HttpServletRequest, then the dispatch is to the URI returned by HttpServletRequest.getRequestURI(). Otherwise, the dispatch is to the URI of the request when it was last dispatched by the container.

      The following sequence illustrates how this will work: 

       
 // REQUEST dispatch to /url/A
 AsyncContext ac = request.startAsync();
 ...
 ac.dispatch(); // ASYNC dispatch to /url/A
 
 // REQUEST to /url/A
 // FORWARD dispatch to /url/B
 request.getRequestDispatcher("/url/B").forward(request,response);
 // Start async operation from within the target of the FORWARD
 // dispatch
 ac = request.startAsync();
 ...
 ac.dispatch(); // ASYNC dispatch to /url/A
 
 // REQUEST to /url/A
 // FORWARD dispatch to /url/B
 request.getRequestDispatcher("/url/B").forward(request,response);
 // Start async operation from within the target of the FORWARD
 // dispatch
 ac = request.startAsync(request,response);
 ...
 ac.dispatch(); // ASYNC dispatch to /url/B

      This method returns immediately after passing the request and response objects to a container managed thread, on which the dispatch operation will be performed. If this method is called before the container-initiated dispatch that called startAsync has returned to the container, the dispatch operation will be delayed until after the container-initiated dispatch has returned to the container.

      The dispatcher type of the request is set to DispatcherType.ASYNC. Unlike forward dispatches, the response buffer and headers will not be reset, and it is legal to dispatch even if the response has already been committed.

      Control over the request and response is delegated to the dispatch target, and the response will be closed when the dispatch target has completed execution, unless ServletRequest.startAsync() or ServletRequest.startAsync(ServletRequest, ServletResponse) are called.

      Any errors or exceptions that may occur during the execution of this method must be caught and handled by the container, as follows:

      1. Invoke, at their onError method, all AsyncListener instances registered with the ServletRequest for which this AsyncContext was created, and make the caught Throwable available via AsyncEvent.getThrowable().
      2. If none of the listeners called AsyncContext.complete() or any of the AsyncContext.dispatch() methods, perform an error dispatch with a status code equal to HttpServletResponse.SC_INTERNAL_SERVER_ERROR, and make the above Throwable available as the value of the RequestDispatcher.ERROR_EXCEPTION request attribute.
      3. If no matching error page was found, or the error page did not call AsyncContext.complete() or any of the AsyncContext.dispatch() methods, call AsyncContext.complete().

      There can be at most one asynchronous dispatch operation per asynchronous cycle, which is started by a call to one of the ServletRequest.startAsync() methods. Any attempt to perform an additional asynchronous dispatch operation within the same asynchronous cycle will result in an IllegalStateException. If startAsync is subsequently called on the dispatched request, then any of the dispatch or AsyncContext.complete() methods may be called.

      Specified by:
      dispatch in interface AsyncContext
      See Also:

    • dispatch

      public void dispatch(String path)
      Description copied from interface: AsyncContext
      Dispatches the request and response objects of this AsyncContext to the given path.

      The path parameter is interpreted in the same way as in ServletRequest.getRequestDispatcher(String), within the scope of the ServletContext from which this AsyncContext was initialized.

      All path related query methods of the request must reflect the dispatch target, while the original request URI, context path, path info, servlet path, and query string may be recovered from the AsyncContext.ASYNC_REQUEST_URI, AsyncContext.ASYNC_CONTEXT_PATH, AsyncContext.ASYNC_PATH_INFO, AsyncContext.ASYNC_SERVLET_PATH, and AsyncContext.ASYNC_QUERY_STRING attributes of the request. These attributes will always reflect the original path elements, even under repeated dispatches.

      There can be at most one asynchronous dispatch operation per asynchronous cycle, which is started by a call to one of the ServletRequest.startAsync() methods. Any attempt to perform an additional asynchronous dispatch operation within the same asynchronous cycle will result in an IllegalStateException. If startAsync is subsequently called on the dispatched request, then any of the dispatch or AsyncContext.complete() methods may be called.

      See AsyncContext.dispatch() for additional details, including error handling.

      Specified by:
      dispatch in interface AsyncContext
      Parameters:
      path - the path of the dispatch target, scoped to the ServletContext from which this AsyncContext was initialized
      See Also:

    • dispatch

      public void dispatch(ServletContext context, String path)
      Description copied from interface: AsyncContext
      Dispatches the request and response objects of this AsyncContext to the given path scoped to the given context.

      The path parameter is interpreted in the same way as in ServletRequest.getRequestDispatcher(String), except that it is scoped to the given context.

      All path related query methods of the request must reflect the dispatch target, while the original request URI, context path, path info, servlet path, and query string may be recovered from the AsyncContext.ASYNC_REQUEST_URI, AsyncContext.ASYNC_CONTEXT_PATH, AsyncContext.ASYNC_PATH_INFO, AsyncContext.ASYNC_SERVLET_PATH, and AsyncContext.ASYNC_QUERY_STRING attributes of the request. These attributes will always reflect the original path elements, even under repeated dispatches.

      There can be at most one asynchronous dispatch operation per asynchronous cycle, which is started by a call to one of the ServletRequest.startAsync() methods. Any attempt to perform an additional asynchronous dispatch operation within the same asynchronous cycle will result in an IllegalStateException. If startAsync is subsequently called on the dispatched request, then any of the dispatch or AsyncContext.complete() methods may be called.

      See AsyncContext.dispatch() for additional details, including error handling.

      Specified by:
      dispatch in interface AsyncContext
      Parameters:
      context - the ServletContext of the dispatch target
      path - the path of the dispatch target, scoped to the given ServletContext
      See Also:

    • complete

      public void complete()
      Description copied from interface: AsyncContext
      Completes the asynchronous operation that was started on the request that was used to initialze this AsyncContext, closing the response that was used to initialize this AsyncContext.

      Any listeners of type AsyncListener that were registered with the ServletRequest for which this AsyncContext was created will be invoked at their onComplete method.

      It is legal to call this method any time after a call to ServletRequest.startAsync() or ServletRequest.startAsync(ServletRequest, ServletResponse), and before a call to one of the dispatch methods of this class. If this method is called before the container-initiated dispatch that called startAsync has returned to the container, then the call will not take effect (and any invocations of AsyncListener.onComplete(AsyncEvent) will be delayed) until after the container-initiated dispatch has returned to the container.

      Specified by:
      complete in interface AsyncContext

    • completeInternal

      public void completeInternal(boolean forceComplete)

    • start

      public void start(Runnable run)
      Description copied from interface: AsyncContext
      Causes the container to dispatch a thread, possibly from a managed thread pool, to run the specified Runnable. The container may propagate appropriate contextual information to the Runnable.
      Specified by:
      start in interface AsyncContext
      Parameters:
      run - the asynchronous handler

    • addListener

      public void addListener(AsyncListener listener)
      Description copied from interface: AsyncContext
      Registers the given AsyncListener with the most recent asynchronous cycle that was started by a call to one of the ServletRequest.startAsync() methods.

      The given AsyncListener will receive an AsyncEvent when the asynchronous cycle completes successfully, times out, results in an error, or a new asynchronous cycle is being initiated via one of the ServletRequest.startAsync() methods.

      AsyncListener instances will be notified in the order in which they were added.

      If ServletRequest.startAsync(ServletRequest, ServletResponse) or ServletRequest.startAsync() is called, the exact same request and response objects are available from the AsyncEvent when the AsyncListener is notified.

      Specified by:
      addListener in interface AsyncContext
      Parameters:
      listener - the AsyncListener to be registered

    • addListener

      public void addListener(AsyncListener listener, ServletRequest servletRequest, ServletResponse servletResponse)
      Description copied from interface: AsyncContext
      Registers the given AsyncListener with the most recent asynchronous cycle that was started by a call to one of the ServletRequest.startAsync() methods.

      The given AsyncListener will receive an AsyncEvent when the asynchronous cycle completes successfully, times out, results in an error, or a new asynchronous cycle is being initiated via one of the ServletRequest.startAsync() methods.

      AsyncListener instances will be notified in the order in which they were added.

      The given ServletRequest and ServletResponse objects will be made available to the given AsyncListener via the getSuppliedRequest and getSuppliedResponse methods, respectively, of the AsyncEvent delivered to it. These objects should not be read from or written to, respectively, at the time the AsyncEvent is delivered, because additional wrapping may have occurred since the given AsyncListener was registered, but may be used in order to release any resources associated with them.

      Specified by:
      addListener in interface AsyncContext
      Parameters:
      listener - the AsyncListener to be registered
      servletRequest - the ServletRequest that will be included in the AsyncEvent
      servletResponse - the ServletResponse that will be included in the AsyncEvent

    • isDispatched

      public boolean isDispatched()

    • isCompletedBeforeInitialRequestDone

      public boolean isCompletedBeforeInitialRequestDone()

    • createListener

      public <T extends AsyncListener> T createListener(Class<T> clazz) throws ServletException
      Description copied from interface: AsyncContext
      Instantiates the given AsyncListener class.

      The returned AsyncListener instance may be further customized before it is registered with this AsyncContext via a call to one of the addListener methods.

      The given AsyncListener class must define a zero argument constructor, which is used to instantiate it.

      This method supports resource injection if the given clazz represents a Managed Bean. See the Jakarta EE platform and CDI specifications for additional details about Managed Beans and resource injection.

      This method supports any annotations applicable to AsyncListener.

      Specified by:
      createListener in interface AsyncContext
      Type Parameters:
      T - the class of the object to instantiate
      Parameters:
      clazz - the AsyncListener class to instantiate
      Returns:
      the new AsyncListener instance
      Throws:
      ServletException - if the given clazz fails to be instantiated

    • setTimeout

      public void setTimeout(long timeout)
      Description copied from interface: AsyncContext
      Sets the timeout (in milliseconds) for this AsyncContext.

      The timeout applies to this AsyncContext once the container-initiated dispatch during which one of the ServletRequest.startAsync() methods was called has returned to the container.

      The timeout will expire if neither the AsyncContext.complete() method nor any of the dispatch methods are called. A timeout value of zero or less indicates no timeout.

      If AsyncContext.setTimeout(long) is not called, then the container's default timeout, which is available via a call to AsyncContext.getTimeout(), will apply.

      The default value is 30000 ms.

      Specified by:
      setTimeout in interface AsyncContext
      Parameters:
      timeout - the timeout in milliseconds

    • getTimeout

      public long getTimeout()
      Description copied from interface: AsyncContext
      Gets the timeout (in milliseconds) for this AsyncContext.

      This method returns the container's default timeout for asynchronous operations, or the timeout value passed to the most recent invocation of AsyncContext.setTimeout(long).

      A timeout value of zero or less indicates no timeout.

      Specified by:
      getTimeout in interface AsyncContext
      Returns:
      the timeout in milliseconds

    • handleError

      public void handleError(Throwable error)

    • initialRequestDone

      public void initialRequestDone()
      Called by the container when the initial request is finished. If this request has a dispatch or complete call pending then this will be started.

    • initialRequestFailed

      public void initialRequestFailed()

    • handleCompletedBeforeInitialRequestDone

      public void handleCompletedBeforeInitialRequestDone()

    • addAsyncTask

      public void addAsyncTask(Runnable runnable)
      Adds a task to be run to the async context. These tasks are run one at a time, after the initial request is finished. If the request is dispatched before the initial request is complete then these tasks will not be run

      This method is intended to be used to queue read and write tasks for async streams, to make sure that multiple threads do not end up working on the same exchange at once

      Parameters:
      runnable - The runnable