Можешь сделать так:
public static ToolMaterial addMeleeMaterial(int maxUses, float damage, int enchantability, Item repair) {
return ((ToolMaterial)EnumHelper.addEnum(ToolMaterial.class, "", new Object[]{0, maxUses, 0, damage - 5.0F, enchantability})).setRepairItem(new ItemStack(repair...