Woah, now. There are some benefits to some of the ingredients in energy drinks.
Caffeine, when taken about an hour before exercise in the correct dosage (around 2-3mg/kg bodyweight), can enhance exercise performance and endurance by 2-15%.
It is also known that simple carbohydrates combined with a highly available source of protein during and after the workout window are vital to both performance and recovery.
The problem is that if you take them both together, as the caffeine kicks in, you'll be experiencing a "downer" from your body's response to the sugar.
That particular drink, however, looks completely worthless, if that's the complete ingredient list. It has neither the carbohydrates you need for energy, nor the caffeine for the stimulant effect.
Ideally, it would be much better to take the mentioned dosage of caffeine an hour before your workout (larger amounts, or the consumption of caffeine more than 2-3 times a week, should be avoided). Then sip on a 20g protein/40g carbohydrate drink during and after your workout. Two separate drinks. Then eat a meal with some protein and lots of complex carbohydrates 1 hour after finishing your training.
Will having that drink kill you? Probably not, as there doesn't seem to be anything in it. However, if that's all you are doing for your workout nutrition...you're screwing yourself over.