Write first draft of Ingredient class

src/main/java/no/ntnu/idatt1002/demo/data/recipes/Ingredient.java

+package no.ntnu.idatt1002.demo.data.recipes;
+
+public class Ingredient {
+
+    private FoodItem foodType;
+    private double amount;
+    private MeasuringUnit unit;
+
+    public Ingredient(FoodItem ingredient, double amount, MeasuringUnit unit) {
+        if(ingredient == null | amount < 0.0f | unit == null) {
+            throw new IllegalArgumentException("The ingredient must have a type, amount and measuring unit.");
+        }
+        this.foodType = ingredient;
+        this.amount = amount;
+        this.unit = unit;
+    }
+
+    public FoodItem getFoodType() {
+        return foodType;
+    }
+
+    public void setFoodType(FoodItem foodType) {
+        if(foodType == null) {
+            throw new IllegalArgumentException("The food type must be set to a valid value of FoodItem.");
+        }
+        this.foodType = foodType;
+    }
+
+    public double getAmount() {
+        return amount;
+    }
+
+    public void setAmount(double amount) {
+        if(amount < 0.0f) {
+            throw new IllegalArgumentException("The amount of an ingredient cannot be zero or negative.");
+        }
+        this.amount = amount;
+    }
+
+    public MeasuringUnit getUnit() {
+        return unit;
+    }
+
+    public void setUnit(MeasuringUnit unit) {
+        if(unit == null) {
+            throw new IllegalArgumentException("The food's measuring unit must be set to a valid value of MeasuringUnit.");
+        }
+        this.unit = unit;
+    }
+
+    @Override
+    public String toString() {
+        return "Ingredient{" +
+                "foodType=" + foodType.label +
+                ", amount=" + amount +
+                ", unit=" + unit.label +
+                '}';
+    }
+
+}