CS04

Application.java

package main.day4.rectangle;

import main.day4.rectangle.controller.MainController;

public class Application {
    public static void main(String[] args) {
        MainController main = new MainController();
        main.start();
    }
}

Calculator.java

package main.day4.rectangle.service;

import main.day4.rectangle.domain.*;
import main.day4.triangle.view.Printer;

public class Calculator {

    public static void calLength(int i, int j) {
        Position a = PositionRepository.positions().get(i);
        Position b = PositionRepository.positions().get(j);

        Length length = new Length(a, b);
        LengthRepository.add(length);
    }

    public static void calThreeLengths() {
        calLength(0, 1);
        calLength(1, 2);
        calLength(2, 0);
    }

    public static Triangle getTriangle() {
        calThreeLengths();
        Length a = LengthRepository.lengths().get(0);
        Length b = LengthRepository.lengths().get(1);
        Length c = LengthRepository.lengths().get(2);

        return new Triangle(a, b, c);
    }

    public static void getResult() {
        int posCnt = PositionRepository.positions().size(); // Position Count

        if (posCnt == 2) { // 점이 2개 일때 (직선)
            calLength(0, 1);
            double result = LengthRepository.lengths().get(0).calVal();
            Printer.printLength(result);
            return;
        }

        if (posCnt == 3) { // 점이 3개 일때 (삼각형)
            Triangle triangle = getTriangle();
            Printer.printArea(triangle.calArea());
            return;
        }

    }
}

Extractor.java

package main.day4.rectangle.service;

import main.day4.rectangle.domain.Position;
import main.day4.rectangle.domain.PositionRepository;

public class Extractor {

    public static void savePos(String input) {
        String[] pos = input.split("-");

        for(int i = 0; i < pos.length; i++) {
            Position eachPos = extractPos(pos[i]);
            PositionRepository.add(eachPos);
        }
    }

    public static Position extractPos(String pos) {
        pos = pos.replace("(", "");
        pos = pos.replace(")", "");
        String[] xy = pos.split(",");

        return new Position(Integer.parseInt(xy[0]), Integer.parseInt(xy[1]));
    }
}

InputView.java

package main.day4.rectangle.view;

public class InputView {
    public static void askPos() {
        System.out.println("> 좌표를 입력해주세요.");
    }
}

Length.java

package main.day4.rectangle.domain;

public class Length {
    private Position a;
    private Position b;

    Length() {

    }

    public Length(Position a, Position b) {
        this.a = a;
        this.b = b;
    }

    public double calVal() {
        return Math.sqrt(
                Math.pow(
                        (a.getX() - b.getX()), 2) + Math.pow((a.getY() - b.getY())
                        , 2)
        );
    }
}

LengthRepository.java

package main.day4.rectangle.domain;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class LengthRepository {
    private static final List<Length> lengths = new ArrayList<>();

    public static List<Length> lengths() {
        return Collections.unmodifiableList(lengths);
    }

    public static boolean add(Length length) {
        return lengths.add(length);
    }
}

MainController.java

package main.day4.rectangle.controller;

import main.day4.rectangle.service.Calculator;
import main.day4.rectangle.service.Extractor;
import main.day4.rectangle.view.InputView;

import java.util.Scanner;

public class MainController {

    public void start() {
        Scanner sc = new Scanner(System.in);
        InputView.askPos();
        String input = sc.nextLine();
        Extractor.savePos(input);

        Calculator.getResult();
    }
}

Position.java

package main.day4.rectangle.domain;

public class Position {
    private int x;
    private int y;

    Position() {

    }

    public Position(int x, int y) {
        this.x = x;
        this.y = y;
    }

    public int getX() {
        return x;
    }

    public int getY() {
        return y;
    }
}

PositionRepository.java

package main.day4.rectangle.domain;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class PositionRepository {
    private static final List<Position> positions = new ArrayList<>();

    public static List<Position> positions() {
        return Collections.unmodifiableList(positions);
    }

    public static boolean add(Position pos) {
        return positions.add(pos);
    }
}

ResultView.java

package main.day4.rectangle.view;

public class ResultView {
    public static void printLength(double result) {
        System.out.println("두 점 사이의 거리는 " + result);
    }

    public static void printArea(double result) {
        System.out.println("삼각형의 넓이는 " + result);
    }
}

Triangle.java

package main.day4.rectangle.domain;

public class Triangle {
    private Position aPos;
    private Position bPos;
    private Position cPos;

    private Length aLeng;
    private Length bLeng;
    private Length cLeng;

    Triangle() {

    }

    public Triangle(Length aLeng, Length bLeng, Length cLeng) {
        this.aLeng = aLeng;
        this.bLeng = bLeng;
        this.cLeng = cLeng;
    }

    public double calArea() {
        return Math.sqrt(
                4 * Math.pow(aLeng.calVal(), 2) * Math.pow(bLeng.calVal(), 2)
                        - Math.pow(
                        (Math.pow(aLeng.calVal(), 2) + Math.pow(bLeng.calVal(), 2) - Math.pow(cLeng.calVal(), 2)
                        ), 2
                )
        ) / 4;
    }
}