| // Dangerous program.
// M2 is virtual in A and overridden in B.
// Compiles and runs
// Default Java semantics.
using System;
// New version of A
class A {
public void M1(){
Console.WriteLine("Method 1");
this.M2();
}
// New method in this version.
// Same name as the dangerous operation in subclass B
public virtual void M2(){
Console.WriteLine("M2 in new version of A");
}
}
class B: A {
public override void M2(){
Console.WriteLine("Dangerous Method 2");
}
}
class Client{
public static void Main(){
A a = new B();
B b = new B();
a.M1(); // Nothing dangerous expected
// Will, however, call the dangerous operation
// because M2 is virtual.
a.M2(); // Makes sense when M2 exists in class A.
// Calls the dangerous method
b.M2(); // Calls the dangerous method.
// This is expected, however.
}
} |