[JAVA] Object-oriented programming learned from Dragon Ball

1. 1. Purpose

• Object-oriented memorandum
• UML design memorandum

2. Overview

The world of Dragon Ball is composed of various warriors such as Goku, Android Cell, and Majin Buu. This time, we will design and implement a small case while focusing on those who are different from ordinary people.

• Specific implementation will be done each time.

3. 3. UML design

UML diagram (class diagram)

Summary of frequently used items

Access modifier (UML diagram)

4. Design-Implementation

Warrior features: Fighting function → Treat as an interface

Fighter.java

interface Fighter {
	void fight();
}

Warriors possess the above functions and have the following characteristics

• Name
• Combat power
• Physical fitness
• Learn techniques
• Perform tricks ... etc

DragonballWarrior.java

public class DragonballWarrior implements Fighter {
	private String name;
	private int property;
	private int HP;

	@Override
	public void fight() {
	}

	public void getSkill() {
	}

	public void doSkill() {
	}
}

Goku can be treated as a subclass of warriors Summarize the common items of warriors and further subdivide

• Saiyan (Super Saiyan under certain conditions / Monkey when looking at the moon)

• Android (serial number / machine name)
• Earthling martial artist
• Planet Namek (self-healing / assimilating damage)

Saiyan.java

public class Saiyan extends DragonballWarrior {
	/** [1:normal / 2:monkey / 3:super-saiyan] */
	private int status;

	public void changeStatus(Saiyan saiyan) {
		this.status = saiyan.status;
	}
}

I want to design a Tenkaichi Budokai that fights warriors

• Field

• Warrior
• Weather

Tenkaichi Budokai-Thinking about the has-a relationship of warriors Define superclass constructors and getters / setters

DragonballWarrior.java

public class DragonballWarrior implements Fighter {
	private String name;
	private int property;
	private int HP;

	/** default constractor */
	DragonballWarrior() {
	}

	DragonballWarrior(String name, int property, int HP) {
		this.name = name;
		this.property = property;
		this.HP = HP;
	}

	@Override
	public void fight() {
	}

	public void getSkill() {
	}

	public void doSkill() {
	}

	// S - getter,setter
	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public int getProperty() {
		return property;
	}

	public void setProperty(int property) {
		this.property = property;
	}

	public int getHP() {
		return HP;
	}

	public void setHP(int hP) {
		HP = hP;
	}
	// E - getter,setter
}

Saiyan.java

public class Saiyan extends DragonballWarrior {
	/** [1:normal / 2:monkey / 3:super-saiyan] */
	private int status = 0;

	public Saiyan(String name, int property, int HP) {
		super(name, property, HP);
	}

	public void changeStatus(Saiyan saiyan) {
		this.status = saiyan.status;
	}

	@Override
	public void doSkill() {
		if (super.getName().equals("Goku")) {
			System.out.println("kamehame-ha");
		}
	}

	@Override
	public void fight() {
		if (super.getName().equals("Goku")) {
			System.out.println("ora-Goku!");
		}
	}

Saiyan.java

public class MartialArtist extends DragonballWarrior {
	public MartialArtist(String name, int property, int HP) {
		super(name, property, HP);
	}

	@Override
	public void doSkill() {
		if (super.getName().equals("Kuririn")) {
			System.out.println("kien-zan");
		}
	}

	@Override
	public void fight() {
		if (super.getName().equals("Kuririn")) {
			System.out.println("oreha-Kuririn!");
		}
	}
}

BattleTournament.java

public class BattleTournament {
	private List<DragonballWarrior> dwlist;

	public static void main(String args[]) {
		List<DragonballWarrior> dwlist = new ArrayList<>();
		dwlist.add(new Saiyan("Goku", 50000, 200));
		dwlist.add(new Saiyan("Vegeta", 40000, 250));
		dwlist.add(new MartialArtist("Kuririn", 3000, 80));
		dwlist.add(new MartialArtist("Kamesennin", 3000, 80));
		for (DragonballWarrior dw : dwlist) {
			dw.fight();
			dw.doSkill();
		}
	}
}

5. Execution result

Execution result.java

ora-Goku!
kamehame-ha
oreha-Kuririn!
kien-zan

It ’s full of stuff, I was able to confirm that polymorphism is working

→ Someday

6. the end

3 months tester → I thought I had to go to basic design and learn design patterns Perfect cell is singleton class design, technique is interface or abstract class and composition relationship

Now I would like to summarize anonymous classes-> generics-> lambda expressions and functional interfaces-> Stream API.