<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">Hi Romain,</div><div class=""><br class=""></div><div class="">Intersting proposal. As I felt reading you that we misse the CompletableFuture stuff in Java 8, I just repeat here that the agreed on fireAsync signatures&nbsp;</div><div class=""><br class=""></div><div class="">&lt;U&nbsp;extends&nbsp;T&gt; CompletionStage&lt;U&gt; fireAsync(U event);</div><div class="">and</div><div class="">&lt;U&nbsp;extends&nbsp;T&gt; CompletionStage&lt;U&gt; fireAsync(U event, Executor executor);<br class=""><br class="">Yeah it’s CompletionStage because Jozef preferred using interfaces in our API, but I guess implementation will use CompletableFuture under the hood to avoid reinventing the wheel.</div><div class=""><br class=""></div><div class="">With this approach your example:</div><div class=""><br class=""></div><div class=""><div class="gmail_quote"><blockquote class="gmail_quote" style="margin: 0px 0px 0px 0.8ex; border-left-width: 1px; border-left-color: rgb(204, 204, 204); border-left-style: solid; padding-left: 1ex;"><div text="#000000" bgcolor="#FFFFFF" class=""><div dir="ltr" class=""><div class="">event.fireAsync(new LetTheWorldKnow()).thenRun(() -&gt; System.out.println("We did it!"));</div></div></div></blockquote></div></div><div class=""><br class=""></div><div class="">will work without adding constraint on observer signature.</div><div class=""><br class=""></div><div class="">Regarding the observer part, we already discuss similar approach. In a former version of my async event doc I proposed using return type on observer to do discrimination between async and sync and Mark made a suggestion near yours during this meeting:</div><div class=""><br class=""></div><div class=""><a href="http://transcripts.jboss.org/meeting/irc.freenode.org/cdi-dev/2015/cdi-dev.2015-02-25-17.06.log.html" class="">http://transcripts.jboss.org/meeting/irc.freenode.org/cdi-dev/2015/cdi-dev.2015-02-25-17.06.log.html</a></div><div class=""><br class=""></div><div class="">(search for the first “signature” in text)</div><div class=""><br class=""></div><div class="">The main drawback of this approach is to let end user generate the returned CompletableFuture. So each async observer should provide a way to construct this completableFuture. The second question is the type param of the returned CompletableFuture. Should we use raw type? Now we could imagine helped to do that but...</div><div class=""><br class=""></div><div class="">Don’t get me wrong, I’d love to find a solution based on this kind of idea, but I fear it will add more complexity than double activation.</div><div class=""><br class=""></div><div class="">Antoine</div><div class=""><br class=""></div><br class=""><div><blockquote type="cite" class=""><div class="">Le 1 avr. 2015 à 09:15, Romain Manni-Bucau &lt;<a href="mailto:rmannibucau@gmail.com" class="">rmannibucau@gmail.com</a>&gt; a écrit :</div><br class="Apple-interchange-newline"><div class=""><p dir="ltr" class="">No, fireAsync is still needed for all the reason we mzntionned - strongest one being the fact we need a return type and cant change fire - but using the return type we have the double activation without introducing a new API. Said otherwise API stays natural on both sides which was my main fear with a fireAsync and an @ObservesAsync (or any other new api we talked about). And we have the bonus to be aligned on SE async which sounds quite interesting for the future.</p>
<div class="gmail_quote">Le 1 avr. 2015 08:48, "Jozef Hartinger" &lt;<a href="mailto:jharting@redhat.com" class="">jharting@redhat.com</a>&gt; a écrit :<br type="attribution" class=""><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
  
    
  
  <div text="#000000" bgcolor="#FFFFFF" class="">
    So instead of calling observers asynchronously you suggest turning
    observers into producers of CompletableFuture that will then be
    completed asynchronously?<br class="">
    <br class="">
    <div class="">On 03/31/2015 06:21 PM, Romain
      Manni-Bucau wrote:<br class="">
    </div>
    <blockquote type="cite" class="">
      <div dir="ltr" class="">// fire side
        <div class="">event.fireAsync(new LetTheWorldKnow()).thenRun(() -&gt;
          System.out.println("We did it!"));</div>
        <div class=""><br class="">
        </div>
        <div class="">// observer side</div>
        <div class="">CompletableFuture iWantToKnow(@Observes LetTheWorldKnow
          event) {}</div>
        <div class=""><br class="">
        </div>
        <div class="">// impl behavior would be like
          CompletableFuture.allOf(allObserverReturnedInstances) to be
          aligned on CompletableFuture behavior I think</div>
        <div class=""><br class="">
        </div>
        <div class="">Am I clearer?</div>
        <div class=""><br class="">
        </div>
      </div>
      <div class="gmail_extra"><br clear="all" class="">
        <div class="">
          <div class="">
            <div dir="ltr" class="">
              <div class="">
                <div dir="ltr" class="">
                  <div class="">
                    <div dir="ltr" class="">
                      <div class="">
                        <div dir="ltr" class="">
                          <div class=""><br class="">
                            <span style="font-size:small" class="">Romain
                              Manni-Bucau</span><br class="">
                            <a href="https://twitter.com/rmannibucau" target="_blank" class="">@rmannibucau</a> | &nbsp;<a href="http://rmannibucau.wordpress.com/" target="_blank" class="">Blog</a>&nbsp;| <a href="https://github.com/rmannibucau" target="_blank" class="">Github</a>&nbsp;| <a href="https://www.linkedin.com/in/rmannibucau" target="_blank" class="">LinkedIn</a>&nbsp;| <a href="http://www.tomitribe.com/" target="_blank" class="">Tomitriber</a></div>
                        </div>
                      </div>
                    </div>
                  </div>
                </div>
              </div>
            </div>
          </div>
        </div>
        <br class="">
        <div class="gmail_quote">2015-03-31 18:15 GMT+02:00 Sven
          Linstaedt <span dir="ltr" class="">&lt;<a href="mailto:sven.linstaedt@gmail.com" target="_blank" class="">sven.linstaedt@gmail.com</a>&gt;</span>:<br class="">
          <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
            <div dir="ltr" class="">
              <div class="">Hi Romain,</div>
              <div class=""><br class="">
              </div>
              I am not sure, I have fully understand how an observer
              with&nbsp;<span style="font-size:12.8000001907349px" class="">CompletableFuture&nbsp;could
                look like. Could you give us an example?&nbsp;</span>
              <div class=""><span style="font-size:12.8000001907349px" class=""><br class="">
                </span></div>
              <div class=""><span style="font-size:12.8000001907349px" class="">Afair&nbsp;</span><span style="font-size:12.8000001907349px" class="">CompletableFuture</span><span style="font-size:12.8000001907349px" class="">&nbsp;was considered
                  to be used in the "trigger" side in order to track
                  async event invocation completion.</span></div>
              <div class=""><span style="font-size:12.8000001907349px" class=""><br class="">
                </span></div>
              <div class=""><span style="font-size:12.8000001907349px" class="">br, Sven</span></div>
            </div>
            <div class="gmail_extra"><br class="">
              <div class="gmail_quote">
                <div class="">
                  <div class="">2015-03-31 18:00 GMT+02:00 Romain
                    Manni-Bucau <span dir="ltr" class="">&lt;<a href="mailto:rmannibucau@gmail.com" target="_blank" class="">rmannibucau@gmail.com</a>&gt;</span>:<br class="">
                  </div>
                </div>
                <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
                  <div class="">
                    <div class="">
                      <div dir="ltr" class="">Hi guys,
                        <div class=""><br class="">
                        </div>
                        <div class="">on async topic if I followed we are at the
                          point where we are looking for an activation
                          on the observer side.</div>
                        <div class=""><br class="">
                        </div>
                        <div class="">Since Java 8 has now CompletableFuture it
                          would be great to use it. Today the spec
                          doesnt use observer returned values so it is
                          mainly a bad practise to have one even if not
                          strictly forbidden - BTW never saw it in real
                          applications - plus spec is not compatible -
                          not specified at all - with&nbsp;CompletableFuture
                          since it is a new API so we can use it as a
                          marker.</div>
                        <div class=""><br class="">
                        </div>
                        <div class="">This is quite interesting for few reasons:</div>
                        <div class="">1- we have our double activation</div>
                        <div class="">2- API is user friendly (observer is async
                          and has an async signature)</div>
                        <div class="">3- open door for future async enhancements
                          (hopefully not in CDI) with composition of
                          these observers</div>
                        <div class=""><br class="">
                        </div>
                        <div class=""><br class="">
                        </div>
                        <div class="">Only point I'm not sure is should these
                          observers support sync events. I don't see
                          anything blocking to do it but can have missed
                          something.</div>
                        <div class=""><br class="">
                        </div>
                        <div class=""><br class="">
                        </div>
                        <div class="">wdyt?</div>
                        <span class=""><font color="#888888" class="">
                            <div class=""><br clear="all" class="">
                              <div class="">
                                <div class="">
                                  <div dir="ltr" class="">
                                    <div class="">
                                      <div dir="ltr" class="">
                                        <div class="">
                                          <div dir="ltr" class="">
                                            <div class="">
                                              <div dir="ltr" class="">
                                                <div class=""><br class="">
                                                  <span style="font-size:small" class="">Romain
                                                    Manni-Bucau</span><br class="">
                                                  <a href="https://twitter.com/rmannibucau" target="_blank" class="">@rmannibucau</a>
                                                  | &nbsp;<a href="http://rmannibucau.wordpress.com/" target="_blank" class="">Blog</a>&nbsp;| <a href="https://github.com/rmannibucau" target="_blank" class="">Github</a>&nbsp;| <a href="https://www.linkedin.com/in/rmannibucau" target="_blank" class="">LinkedIn</a>&nbsp;|
                                                  <a href="http://www.tomitribe.com/" target="_blank" class="">Tomitriber</a></div>
                                              </div>
                                            </div>
                                          </div>
                                        </div>
                                      </div>
                                    </div>
                                  </div>
                                </div>
                              </div>
                            </div>
                          </font></span></div>
                      <br class="">
                    </div>
                  </div>
                  _______________________________________________<br class="">
                  cdi-dev mailing list<br class="">
                  <a href="mailto:cdi-dev@lists.jboss.org" target="_blank" class="">cdi-dev@lists.jboss.org</a><br class="">
                  <a href="https://lists.jboss.org/mailman/listinfo/cdi-dev" target="_blank" class="">https://lists.jboss.org/mailman/listinfo/cdi-dev</a><br class="">
                  <br class="">
                  Note that for all code provided on this list, the
                  provider licenses the code under the Apache License,
                  Version 2 (<a href="http://www.apache.org/licenses/LICENSE-2.0.html" target="_blank" class="">http://www.apache.org/licenses/LICENSE-2.0.html</a>).
                  For all other ideas provided on this list, the
                  provider waives all patent and other intellectual
                  property rights inherent in such information.<br class="">
                </blockquote>
              </div>
              <br class="">
            </div>
          </blockquote>
        </div>
        <br class="">
      </div>
      <br class="">
      <fieldset class=""></fieldset>
      <br class="">
      <pre class="">_______________________________________________
cdi-dev mailing list
<a href="mailto:cdi-dev@lists.jboss.org" target="_blank" class="">cdi-dev@lists.jboss.org</a>
<a href="https://lists.jboss.org/mailman/listinfo/cdi-dev" target="_blank" class="">https://lists.jboss.org/mailman/listinfo/cdi-dev</a>

Note that for all code provided on this list, the provider licenses the code under the Apache License, Version 2 (<a href="http://www.apache.org/licenses/LICENSE-2.0.html" target="_blank" class="">http://www.apache.org/licenses/LICENSE-2.0.html</a>). For all other ideas provided on this list, the provider waives all patent and other intellectual property rights inherent in such information.</pre>
    </blockquote>
    <br class="">
  </div>

</blockquote></div>
_______________________________________________<br class="">cdi-dev mailing list<br class=""><a href="mailto:cdi-dev@lists.jboss.org" class="">cdi-dev@lists.jboss.org</a><br class="">https://lists.jboss.org/mailman/listinfo/cdi-dev<br class=""><br class="">Note that for all code provided on this list, the provider licenses the code under the Apache License, Version 2 (http://www.apache.org/licenses/LICENSE-2.0.html). For all other ideas provided on this list, the provider waives all patent and other intellectual property rights inherent in such information.</div></blockquote></div><br class=""></body></html>