Simple Battery is a misdemeanor offense in Georgia that carries up to one year in the county jail upon conviction. However, the sentencing range for a first offense is generally probation for a year with a minimal jail sentence. Much depends on your particular situation and the posture of the victim, the arresting officer and/or prosecutor.
In simple battery situations, the alleged victim's input can often sway a prosecutor either to drop the charges or increase the sentencing range that the State will seek before the court. Your friend should consult an attorney to determine if there are any viable legal defenses such as provocation or self-defense. Likewise, an attorney will be able to negotiate on your friends behalf in order to provide him the best options possible should he choose not to take the case to trial.
It is not uncommon for simple battery convictions to mandate anger management class. However, sometimes anger management class can be subsituted for a conviction, i.e. the prosecutor will dismiss the charges if your friend seeks 'help for his anger problem.' This must be negotiated with the prosecuting authority. A skilled defense attorney will know what to do when representing your friend. If your friend cannot afford an attorney, he may apply for the services of the public defender: criminal law specialists who do nothing but criminal defense and often have excellent experience handling all types of criminal cases. Either way - he should hire an attorney.