private void addBatExperience(int xp){
  if (!worldObj.isRemote) {
    setBatExperience(Integer.valueOf(getBatExperience() + xp));
  }
}

private void addBatExperience ( int xp ) { if ( ! worldObj . isRemote ) { setBatExperience ( Integer . valueOf ( getBatExperience ( ) + xp ) ) ; } }
bat levels up with all damage it inflicts in combat .
