Question

1 What is a difference between override and new when it comes to inheritance?

2 What is the difference between List<type> and ArrayList? AND Which one should you use and why?

3. If I have a file test.txt, and have committed it to the git repository using: $ git commit test.txt Then made some changes, what command (or option) do you use to get the original file back (ie restore the contents of the committed file)?

4 What command (or option) do you use to initialize a directory as a git repository?

5. List 2 decentrialized source code managment systems

6. What is the purpose of source code management systems?

7. Would this code work? Why or why not?

intval = 5;
Textbox1.Text = val;

8.... Create an example where you have a base class A and a derived class B. class A has a method called func which has the following prototype – 3pt:

public virtual void func()

Create class B such that it replaces the functionality of the func method with new functionality.

Answer 1

1)

Override: When a method of a base class is overridden in a derived class, the version in the derived class is used, even if the calling code didn't "know" that the object was an instance of the derived class.

New: If you use the new keyword instead of override, the method in the derived class doesn't override the method in the base class, it merely hides it.

2)

-> There's no difference between list implementations in both of your examples. There's however a difference in a way you can further use variable myList in your code.

-->When you define your list as:

-->List myList = new ArrayList();

-->you can only call methods and reference members that are defined in the List interface. If you define it as:

-->ArrayList myList = new ArrayList();

--> you'll be able to invoke ArrayList-specific methods and use ArrayList-specific members in addition to those whose definitions are inherited from List.

--> Nevertheless, when you call a method of a List interface in the first example, which was implemented in ArrayList, the method from ArrayList will be called (because the List interface doesn't implement any methods).

3)

$ git reset --soft HEAD^
        $ ... do something else to come up with the right tree ...
        $ git commit -c ORIG_HEAD

4)git-init-db(1) ============== NAME ---- git-init-db - Creates an empty Git repository SYNOPSIS -------- [verse] 'git init-db' [-q | --quiet] [--bare] [--template=] [--separate

5)

DELTA BASED VERSION CONTROL

SNAPSHOT BASED VERSION CONTROL

6)

• Using revision control software, a programmer or team of programmers may use several approaches for software development.
• Locally, developers must all use the same computer system, which may be the revision control system.
• In a distributed model, developers work directly with a local repository, where their individual source code revisions are collected.
• The developers then update the central repository with their local revisions so that revisions can be shared among developers.

7)Not work.

Because, we can store an int value in a variable of type int. But we can't store a int value to a text file. It won't work anyway.

8)

public clsas A{

public vertual void func( ) { }

}

public clsas B : A{

public override void func( ) { }

}