lab5

lab/lab5/Question3/Cat.java

@@ -0,0 +1,64 @@
+/*
+ * Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
+ * Date: 2022-03-19
+ * Description: Cat class
+ */
+
+public class Cat {
+	/**
+	 * Cat's name
+	 */
+	private String name;
+
+	/**
+	 * Cat's weight
+	 */
+	private double weight;
+
+	/**
+	 * Constructor. Initialize the name and weight of the cat
+	 */
+	public Cat(String name, double weight) {
+		this.name = name;
+		this.weight = weight;
+	}
+
+	/**
+	 * Get the name of the cat
+	 *
+	 * @return name of the cat
+	 */
+	public String getName() {
+		return name;
+	}
+
+	/**
+	 * Get the weight of the cat
+	 *
+	 * @return weight of the cat
+	 */
+	public double getWeight() {
+		return weight;
+	}
+
+	/**
+	 * Feeding a cat adds 1.0 to its weight
+	 */
+	public void feed() {
+		weight += 1.0;
+	}
+
+	/**
+	 * Test
+	 */
+	public static void testCat() {
+		Cat c = new Cat("Meow", 2.0);
+
+		System.out.println(c.getName() == "Meow");
+		System.out.println(c.getWeight() == 2.0);
+		c.feed();
+		// The name is still the same but the weight increased by 1.0:
+		System.out.println(c.getName() == "Meow");
+		System.out.println(c.getWeight() == 3.0);
+	}
+}

lab/lab5/Question3/Dog.java

@@ -0,0 +1,63 @@
+/*
+ * Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
+ * Date: 2022-03-19
+ * Description: Dog class
+ */
+
+public class Dog {
+	/**
+	 * Dog's name
+	 */
+	private String name;
+
+	/**
+	 * Dog's weight
+	 */
+	private double weight;
+
+	/**
+	 * Constructor. Initialize the name and weight of the dog
+	 */
+	public Dog(String name, double weight) {
+		this.name = name;
+		this.weight = weight;
+	}
+
+	/**
+	 * Get the name of the dog
+	 *
+	 * @return name of the dog
+	 */
+	public String getName() {
+		return name;
+	}
+
+	/**
+	 * Get the weight of the dog
+	 *
+	 * @return weight of the dog
+	 */
+	public double getWeight() {
+		return weight;
+	}
+
+	/**
+	 * Feeding a dog adds 2.0 to its weight
+	 */
+	public void feed() {
+		weight += 2.0;
+	}
+
+	/**
+	 * Test
+	 */
+	public static void testDog() {
+		Dog d = new Dog("Woof", 2.0);
+		System.out.println(d.getName() == "Woof");
+		System.out.println(d.getWeight() == 2.0);
+		d.feed();
+		// The name is still the same but the weight increased by 2.0:
+		System.out.println(d.getName() == "Woof");
+		System.out.println(d.getWeight() == 4.0);
+	}
+}

lab/lab5/Question3/Start.java

@@ -0,0 +1,7 @@
+public class Start {
+	public static void main(String[] args) {
+		Cat.testCat();
+		Dog.testDog();
+		Student.testStudent();
+	}
+}

lab/lab5/Question3/Student.java

@@ -0,0 +1,56 @@
+/*
+ * Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
+ * Date: 2022/03/19
+ * Description: Student class
+ */
+
+public class Student {
+	/**
+	 * Student's name
+	 */
+	private String name;
+
+	/**
+	 * Student's pet
+	 */
+	private Cat pet;
+
+	/**
+	 * Constructor
+	 */
+	public Student(String name, Cat pet) {
+		this.name = name;
+		this.pet = pet;
+	}
+
+	/**
+	 * Getter for name
+	 *
+	 * @return String
+	 */
+	public String getName() {
+		return name;
+	}
+
+	/**
+	 * Getter for pet
+	 *
+	 * @return Cat
+	 */
+	public Cat getPet() {
+		return pet;
+	}
+
+	/**
+	 * Test
+	 */
+	public static void testStudent() {
+		Cat cat = new Cat("Tom", 1.0);
+		Student student = new Student("Walter", cat);
+		System.out.println(student.getName() == "Walter");
+		System.out.println(student.getPet() == cat);
+		System.out.println(student.getPet().getName() == "Tom");
+		System.out.println(student.getPet().getWeight() == 1.0);
+	}
+
+}