From bd3c2688f429110115af79653a6157f6a92f6765 Mon Sep 17 00:00:00 2001
From: ivs <ivsucram@gmail.com>
Date: Wed, 23 Oct 2024 18:53:40 +0800
Subject: [PATCH] Adding extra exercises for Polymorphism and Inheritance

---
 T5Q2-Marcus/T5Q2-Marcus.iml | 11 +++++++++++
 T5Q2-Marcus/src/ClassA.java |  9 +++++++++
 T5Q2-Marcus/src/ClassB.java |  9 +++++++++
 T5Q2-Marcus/src/ClassC.java |  9 +++++++++
 T5Q2-Marcus/src/Main.java   | 25 +++++++++++++++++++++++++
 5 files changed, 63 insertions(+)
 create mode 100644 T5Q2-Marcus/T5Q2-Marcus.iml
 create mode 100644 T5Q2-Marcus/src/ClassA.java
 create mode 100644 T5Q2-Marcus/src/ClassB.java
 create mode 100644 T5Q2-Marcus/src/ClassC.java
 create mode 100644 T5Q2-Marcus/src/Main.java

diff --git a/T5Q2-Marcus/T5Q2-Marcus.iml b/T5Q2-Marcus/T5Q2-Marcus.iml
new file mode 100644
index 0000000..c90834f
--- /dev/null
+++ b/T5Q2-Marcus/T5Q2-Marcus.iml
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
\ No newline at end of file
diff --git a/T5Q2-Marcus/src/ClassA.java b/T5Q2-Marcus/src/ClassA.java
new file mode 100644
index 0000000..754836c
--- /dev/null
+++ b/T5Q2-Marcus/src/ClassA.java
@@ -0,0 +1,9 @@
+public class ClassA {
+    public void method1() {
+        System.out.println("ClassA.method1");
+    }
+
+    public void method2() {
+        System.out.println("ClassA.method2");
+    }
+}
diff --git a/T5Q2-Marcus/src/ClassB.java b/T5Q2-Marcus/src/ClassB.java
new file mode 100644
index 0000000..5515d18
--- /dev/null
+++ b/T5Q2-Marcus/src/ClassB.java
@@ -0,0 +1,9 @@
+public class ClassB extends ClassA {
+    public void method2() {
+        System.out.println("ClassB.method2");
+    }
+
+    public void method3() {
+        System.out.println("ClassB.method3");
+    }
+}
diff --git a/T5Q2-Marcus/src/ClassC.java b/T5Q2-Marcus/src/ClassC.java
new file mode 100644
index 0000000..9f4f167
--- /dev/null
+++ b/T5Q2-Marcus/src/ClassC.java
@@ -0,0 +1,9 @@
+public class ClassC extends ClassB {
+    public void method3() {
+        System.out.println("ClassC.method3");
+    }
+
+    public void method4() {
+        System.out.println("ClassC.method4");
+    }
+}
diff --git a/T5Q2-Marcus/src/Main.java b/T5Q2-Marcus/src/Main.java
new file mode 100644
index 0000000..f764a31
--- /dev/null
+++ b/T5Q2-Marcus/src/Main.java
@@ -0,0 +1,25 @@
+public class Main {
+    public static void main(String[] args) {
+        // I
+//        ClassA a = new ClassB();
+//        ClassB b = (ClassB) a;
+//        b.method2(); // ClassB.method2
+//        b.method1(); // ClassA.method1
+
+        // II
+//        ClassA c = new ClassB();
+//        ClassC d = (ClassC) c; // Runtime error here
+//        d.method3(); // Never executed
+
+        // III
+//        ClassA e = new ClassC();
+//        ClassB f = (ClassB) e;
+//        f.method3(); // ClassC.method3
+//        f.method2(); // ClassB.method2
+//        f.method1(); // ClassA.method1
+
+        // IV
+//        ClassC g = (ClassC) new ClassA(); // Runtime error
+//        g.method1(); // never executed
+    }
+}
\ No newline at end of file