update,

_resources/it114105/itp4510/Lab01/Lab1.2/q1/Coffee.java

@@ -0,0 +1,22 @@
+public class Coffee extends Drink {
+    protected boolean isSweet;
+
+    public Coffee(String name, int price, int volume, boolean isSweet) {
+        super(name, price, volume);
+        this.isSweet = isSweet;
+    }
+
+    public String toString() {
+        if (isSweet)
+            return super.toString() + ", sweet";
+        else
+            return super.toString() + ", not sweet";
+    }
+
+    public void setPrice(int price) {
+        if (price < 10)
+            this.price = 10;
+        else
+            super.setPrice(price);
+    }
+}

_resources/it114105/itp4510/Lab01/Lab1.2/q1/Drink.java

@@ -0,0 +1,19 @@
+public class Drink extends Food {
+    protected int volume;
+
+    public Drink(String name, int price, int volume) {
+        super(name, price);
+        this.volume = volume;
+    }
+
+    public void setPrice(int price) {
+        if (price < 5)
+            this.price = 5;
+        else
+            this.price = price;
+    }
+
+    public String toString() {
+        return super.toString() + ", volume=" + volume;
+    }
+}

_resources/it114105/itp4510/Lab01/Lab1.2/q1/Food.java

@@ -0,0 +1,25 @@
+public class Food {
+    protected String name;
+    protected int price;
+
+    public Food() {
+        name = null;
+        price = 0;
+    }
+
+    public Food(String name, int price) {
+        this.name = name;
+        setPrice(price);
+    }
+
+    public String toString() {
+        return "name=" + name + ", price=" + price;
+    }
+
+    public void setPrice(int price) {
+        if (price >= 0)
+            this.price = price;
+        else
+            this.price = 0;
+    }
+}

_resources/it114105/itp4510/Lab01/Lab1.2/q1/TestFood.java

@@ -0,0 +1,12 @@
+public class TestFood {
+    public static void main(String s[]) {
+        Food f[] = new Food[4];
+        f[0] = new Drink("Pepsi", 7, 250);
+        f[1] = new Coffee("Cappuccino", 13, 200, true);
+        f[2] = new Drink("Orange Juice", -10, 180);
+        f[3] = new Coffee("Ireland", -11, 200, false);
+        for (int i = 0; i < f.length; i++) {
+            System.out.println("Food " + i + ": " + f[i]);
+        }
+    }
+}