How to make recipe return an input item

I am a starter to coding and only started because I wanted to make something for minecraft and thought it wouldn't be too hard, I got my mod working but i want to make a recipe where it makes an item but one of the crafting items stays and doesn't get used up like the buckets when making a cake. I don't know what code to put where and keep getting errors, I hear somewhere that when declaring the item you gave it the container property but it doesn't allow the item name.

package com.mani_cwaf.ruby_items.items;

import com.mani_cwaf.ruby_items.Ruby_Items;
import net.minecraft.item.Item;

public class RubyRefiner extends Item {

    public RubyRefiner() {
        super(new Properties()
                .group(Ruby_Items.TAB_RUBY).maxStackSize(1).containerItem(RubyRefiner));
    }

}

that entry into .containerItem() keeps giving the errror "expression expected", what should I do?