상속예제

// Overloading
// Overriding
 
public class Animal extends Object {
    public void breath() {
        System.out.println("Animal Breath");
    }
}
 

public class Cat extends Animal {
    public void Meow() {
        System.out.println("Cat Meow");
    }
    public void breath() {
        System.out.println("Cat Breath");
    }
}
 

 
public class Dog extends Animal {
    public void Bark() {
        System.out.println("Dog Bark");
    }
    public void breath() {
        System.out.println("Dog Breath");
    }
}
 

public class Database {
    public void open() {
        System.out.println("Database Open");
    }
}
 

public class MySql extends Database {
    public void open() {
        System.out.println("MySql Open");
    }
}
 

public class Oracle extends Database {
    public void open() {
        System.out.println("Oracle Open");
    }
}
 

public class DbExecutor {
    static Database CreateDatabase(String dbname) {
        Database db = null;
        switch(dbname) {
            case "MySql":
                db = new MySql();
                break;
            case "Oracle":
                db = new Oracle();
                break;
        }
        return db;
    }
    public static void main(String[] args) {        
        Database db = CreateDatabase("MySql");
        db.open();
        Database db2 = CreateDatabase("Oracle");
        db2.open();
        
 
    // Database db = CreateDatabase("MySql");
    // db.open();
            
    // Database db2 = CreateDatabase("Oracle");
    // db2.open();
 
    }
 
}