Solved–Homework 3 –Solution

Description

Problem:

We will expand our Warrior a little. Each Warrior will have a weapon. He is “born” with it, i.e. the weapon is created together with the warrior. It can only be accessed by him. It provides him with his strength. In battle, weapons lose their edge and weaken. When a Warrior’s weapon loses all of its strength, the Warrior himself dies.

Implementation

What are the types of things in the problem? We will need a class for each type.

What do the things / types do? These “behaviors” should be represented as methods.

Weapons have both a name and a strength. The weapon is created together with the Warrior and cannot be accessed by anyone else.

The input file needs to change a little. When a Warrior is created, instead of simply specifying his name and strength, the command will specify the Warrior’s name as well as his Weapon’s name and its strength.

The Status report will also be modified to show the name of the Warrior’s Weapon.

No one can access a warrior’s weapon accept the warrior himself. But the weapon is what actually holds the warrior’s strength. How does this effect the programming? Any time the code needs to know or change the warrior’s strength, the warrior then asks the weapon what the strength is or tells the weapon that the strength needs to be changed. This represents the idea of delegation. We will see this concept frequently, where one object requests that another object do some task.

Input

Our sample input file might now look like:

Warrior Jim Glamdring 42

Warrior Lancelot Naegling 15

Warrior Arthur Excalibur 15

Warrior Torvalds Narsil 20

Warrior Gates Orcrist 8

Status

Battle Arthur Lancelot

Battle Jim Lancelot

Battle Torvalds Gates

Battle Gates Lancelot

Status

Output

The corresponding output would be:

There are: 5 warriors

Warrior: Jim, weapon: Glamdring, 42

Warrior: Lancelot, weapon: Naegling, 15

Warrior: Arthur, weapon: Excalibur, 15

Warrior: Torvalds, weapon: Narsil, 20

Warrior: Gates, weapon: Orcrist, 8

Arthur battles Lancelot

Mutual Annihilation: Arthur and Lancelot die at each other’s hands

Jim battles Lancelot

He’s dead, Jim

Torvalds battles Gates

Torvalds defeats Gates

Gates battles Lancelot

Oh, NO! They’re both dead! Yuck!

There are: 5 warriors

Warrior: Jim, weapon: Glamdring, 42

Warrior: Lancelot, weapon: Naegling, 0

Warrior: Arthur, weapon: Excalibur, 0

Warrior: Torvalds, weapon: Narsil, 12

Warrior: Gates, weapon: Orcrist, 0