Rewrite of the Custom item into RecipeItem

and Ingredient with subclasses
Implemented adding custom items to Ingredients
Added support for plugin-items

src/com/dre/brewery/recipe/SimpleItem.java

@@ -0,0 +1,151 @@
+package com.dre.brewery.recipe;
+
+import com.dre.brewery.P;
+import org.bukkit.Material;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * Simple Minecraft Item with just Material
+ */
+public class SimpleItem extends RecipeItem implements Ingredient {
+
+	private Material mat;
+	private short dur; // Old Mc
+
+
+	public SimpleItem(Material mat) {
+		this(mat, (short) 0);
+	}
+
+	public SimpleItem(Material mat, short dur) {
+		this.mat = mat;
+		this.dur = dur;
+	}
+
+	@Override
+	public boolean hasMaterials() {
+		return mat != null;
+	}
+
+	public Material getMaterial() {
+		return mat;
+	}
+
+	@Override
+	public List<Material> getMaterials() {
+		List<Material> l = new ArrayList<>(1);
+		l.add(mat);
+		return l;
+	}
+
+	@NotNull
+	@Override
+	public Ingredient toIngredient(ItemStack forItem) {
+		return ((SimpleItem) getMutableCopy());
+	}
+
+	@NotNull
+	@Override
+	public Ingredient toIngredientGeneric() {
+		return ((SimpleItem) getMutableCopy());
+	}
+
+	@Override
+	public boolean matches(ItemStack item) {
+		if (!mat.equals(item.getType())) {
+			return false;
+		}
+		//noinspection deprecation
+		return P.use1_13 || dur == item.getDurability();
+	}
+
+	@Override
+	public boolean matches(Ingredient ingredient) {
+		if (isSimilar(ingredient)) {
+			return true;
+		}
+		if (ingredient instanceof RecipeItem) {
+			if (!((RecipeItem) ingredient).hasMaterials()) {
+				return false;
+			}
+			if (ingredient instanceof CustomItem) {
+				// Only match if the Custom Item also only defines material
+				// If the custom item has more info like name and lore, it is not supposed to match a simple item
+				CustomItem ci = (CustomItem) ingredient;
+				return !ci.hasLore() && !ci.hasName() && mat == ci.getMaterial();
+			}
+		}
+		return false;
+	}
+
+	@Override
+	public boolean isSimilar(Ingredient item) {
+		if (this == item) {
+			return true;
+		}
+		if (item instanceof SimpleItem) {
+			SimpleItem si = ((SimpleItem) item);
+			return si.mat == mat && si.dur == dur;
+		}
+		return false;
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		if (this == o) return true;
+		if (o == null || getClass() != o.getClass()) return false;
+		if (!super.equals(o)) return false;
+		SimpleItem item = (SimpleItem) o;
+		return dur == item.dur &&
+			mat == item.mat;
+	}
+
+	@Override
+	public int hashCode() {
+		return Objects.hash(super.hashCode(), mat, dur);
+	}
+
+	@Override
+	public String toString() {
+		return "SimpleItem{" +
+			"mat=" + mat.name().toLowerCase() +
+			" amount=" + getAmount() +
+			'}';
+	}
+
+	@Override
+	public void saveTo(DataOutputStream out) throws IOException {
+		out.writeUTF("SI");
+		out.writeUTF(mat.name());
+		out.writeShort(dur);
+	}
+
+	public static SimpleItem loadFrom(ItemLoader loader) {
+		try {
+			DataInputStream in = loader.getInputStream();
+			Material mat = Material.getMaterial(in.readUTF());
+			if (mat != null) {
+				SimpleItem item = new SimpleItem(mat, in.readShort());
+				return item;
+			}
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+		return null;
+	}
+
+	// Needs to be called at Server start
+	public static void registerItemLoader() {
+		Ingredient.registerForItemLoader("SI", SimpleItem::loadFrom);
+	}
+
+}
+