In general, yes. Though it might require you making a motion to dismiss. Different courts have different practices when an officer is a no-show.
Hence one reason for the dismissal request (time and no prosecution). You can request to have the matter dismissed on May 7th if the officer is a no-show, or, the court may decide to continue the matter to another date still within the 45 day window. If you accept the new date,the argument can be made that you agreed to waive time.versus waiting July/ August and having the court say, "hey you got your continuance, we're going to reschedule anyway b/c the officer has a good reason..."
If the court does not dismiss on its own accord, you may have to make the request on your own. Though, the odds of the officer not showing on May 7th may be small. If the citing officer was CHP or a traffic officer with a local agency, he or she lives for traffic court. A patrol officer, well, you may have a slightly better chance, but in some counties the FTA rate for officers is about 2% while others it can be closer to a third. If the officer shows (and he probably will), you may have to decide whether to fight the case or not. You may also receive an offer of traffic school in exchange for a guilty or no contest plea prior to taking the stand at trial (this is common in many courts after attendance) and told that Traffic School may not be an option if you are found guilty. It may then be tough choice time.

