[SOLVED] What is the equivalent of the code written by jetty.continuation in Jakarta.server.AsyncContext?

What is the equivalent of the code written by jetty.continuation in Jakarta.server.AsyncContext?

I want to upgrade my project from jetty 9 to 12. Since the jetty.continuation is deprecated, I want to replace the following code snippet using AsyncContext class.

        Continuation cont = ContinuationSupport.getContinuation(request);
         .
         .
         .
        cont.setTimeout(suspendMs);
        cont.suspend();

what is the code equivalent?

which method does implement "suspend" in AsyncContext class?

Solution

The best source of advice for moving from Jetty Continuations (deprecated in Jetty 8 btw, removed in Jetty 10), is to look at the Servlet3Continuations.java source in the jetty-9.4.x branch.

Methods like suspend() and resume() are not a 1::1 method call on AsyncContext, but in fact multiple method calls.

Continuation to AsyncContext

Continuation.setTimeout(long) ::
```
AsyncContext.setTimeout(long);
```

Continuation.suspend() ::

HttpServletRequest.startAsync();
HttpServletRequest.setTimeout(...);
HttpServletRequest.addListener(AsyncListener); // handles onTimeout and onComplete

Continuation.suspend(ServletResponse response) ::

HttpServletRequest.startAsync(request, response);
HttpServletRequest.setTimeout(...);
HttpServletRequest.addListener(AsyncListener); // handles onTimeout and onComplete

Continuation.resume() ::
```
AsyncContext.dispatch();
```
Continuation.complete() ::
```
AsyncContext.complete();
```
Continuation.isSuspended() ::
```
HttpServletRequest.isAsyncStarted();
```
Continuation.isResumed() ::
```
// no servlet API for this
```
Continuation.isExpired() ::
```
// no servlet API for this
```

Continuation.isInitial() ::

if (HttpServletRequest.getDispatcherType() != DispatcherType.ASYNC) {
  // possibly the initial request
  // note, this could be a REQUEST / INCLUDE / FORWARD / ERROR dispatch
}

Continuation.isResponseWrapped() ::
```
// no servlet API for this
```

Continuation.getServletResponse() ::

AsyncContext.getRequest();
AsyncContext.getResponse();

Continuation.addContinuationListener(ContinuationListener) ::
```
AsyncContext.addListener(AsyncListener);
```

Continuation.setAttribute(String, Object) ::

HttpServletRequest.setAttribute(String, Object);

Continuation.getAttribute(String) ::

HttpServletRequest.getAttribute(String);

Continuation.removeAttribute(String) ::

HttpServletRequest.removeAttribute(String);

Continuation.undispatch() ::
```
// no servlet API for this
```