Need help with this error.

import java.util.List;
import net.minecraft.creativetab.CreativeTabs;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.init.MobEffects;
import net.minecraft.item.EnumRarity;
import net.minecraft.item.Item;
import net.minecraft.item.ItemFood;
import net.minecraft.item.ItemStack;
import net.minecraft.potion.PotionEffect;
import net.minecraft.world.World;
import quplet.moreMaterials.mod.Reference;

public class ItemSilverApple extends ItemFood {

public ItemSilverApple() {
super(4, 1.0F, false);
setUnlocalizedName(Reference.ModItems.SILVER_APPLE.getUnlocalizedName());
setRegistryName(Reference.ModItems.SILVER_APPLE.getRegistryName());
setCreativeTab(CreativeTabs.FOOD);
setAlwaysEdible();
setHasSubtypes(true);
}

public boolean hasEffect(ItemStack stack) {
return stack.getMetadata() > 0;
}

public EnumRarity getRarity(ItemStack stack)
{
return stack.getMetadata() == 0 ? EnumRarity.UNCOMMON : EnumRarity.RARE;
}

public void onFoodEaten(ItemStack stack, World worldIn, EntityPlayer player)
{
if(!worldIn.isRemote) {
if(stack.getMetadata() > 0) {

player.addPotionEffect(new PotionEffect(MobEffects.HASTE, 3000, 1));
player.addPotionEffect(new PotionEffect(MobEffects.STRENGTH, 1250, 1));
player.addPotionEffect(new PotionEffect(MobEffects.NIGHT_VISION, 3000, 0));
}
else {

player.addPotionEffect(new PotionEffect(MobEffects.HASTE, 750, 1));
player.addPotionEffect(new PotionEffect(MobEffects.STRENGTH, 500, 0));
}
}

}
public void getSubItems(Item itemIn, CreativeTabs tab, List<ItemStack> subItems)
{
subItems.add(new ItemStack(itemIn));
subItems.add(new ItemStack(itemIn, 1, 1));
}

}