[NP] Evaluator

Дадена е класата Applicant (кандидат за евалуација) со име, кредитен резултат (credit score), работен стаж (experience) и дали има криминално досие (criminal record). Исто така, даден е интерфејс за евалуација на кандидати Evaluator со еден метод boolean evaluate(Applicant applicant) и енумерација со следните видови на евалуатори:

Кандидатот ја поминува евалуацијата (методот враќа true) ако:

NO_CRIMINAL_RECORD - нема криминално досие
MORE_EXPERIENCE - има барем 10 години работен стаж
MORE_CREDIT_SCORE - има кредитен резултат од минимум 500
NO_CRIMINAL_RECORD_AND_MORE_EXPERIENCE - нема криминално досие и има барем 10 години работен стаж
MORE_EXPERIENCE_AND_MORE_CREDIT_SCORE - има барем 10 години работен стаж и има кредитен резултат од минимум 500
NO_CRIMINAL_RECORD_AND_MORE_CREDIT_SCORE - нема криминално досие и има кредитен резултат од минимум 500.
Ваша задача е да го имплементирате методот build(Evaluator.TYPE type) во класата EvaluatorBuilder, кој ќе враќа објект од соодветна имплементација на интерфејсот Evaluator за соодветниот тип на евалуација. Ако типот на евалуација не е некој од наведените, методот треба да фрли исклучок од тип InvalidEvaluation.

За добро дизајнирано решение (ќе биде објавено по завршувањето на испитот) ќе се добиваат бонус 10 поени.

Почетен код:

import java.util.Scanner;

public class ApplicantEvaluationTest {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String name = scanner.nextLine();
        int creditScore = scanner.nextInt();
        int employmentYears = scanner.nextInt();
        boolean hasCriminalRecord = scanner.nextBoolean();
        int choice = scanner.nextInt();
        Applicant applicant = new Applicant(name, creditScore, employmentYears, hasCriminalRecord);
        Evaluator.TYPE type = Evaluator.TYPE.values()[choice];
        Evaluator evaluator = null;
        try {
            evaluator = EvaluatorBuilder.build(type);
            System.out.println("Applicant");
            System.out.println(applicant);
            System.out.println("Evaluation type: " + type.name());
            if (evaluator.evaluate(applicant)) {
                System.out.println("Applicant is ACCEPTED");
            } else {
                System.out.println("Applicant is REJECTED");
            }
        } catch (InvalidEvaluation invalidEvaluation) {
            System.out.println("Invalid evaluation");
        }
    }
}

class Applicant {
    private String name;

    private int creditScore;
    private int employmentYears;
    private boolean hasCriminalRecord;

    public Applicant(String name, int creditScore, int employmentYears, boolean hasCriminalRecord) {
        this.name = name;
        this.creditScore = creditScore;
        this.employmentYears = employmentYears;
        this.hasCriminalRecord = hasCriminalRecord;
    }

    public String getName() {
        return name;
    }

    public int getCreditScore() {
        return creditScore;
    }

    public int getEmploymentYears() {
        return employmentYears;
    }

    public boolean hasCriminalRecord() {
        return hasCriminalRecord;
    }

    @Override
    public String toString() {
        return String.format("Name: %s\nCredit score: %d\nExperience: %d\nCriminal record: %s\n",
                name, creditScore, employmentYears, hasCriminalRecord ? "Yes" : "No");
    }
}

interface Evaluator {
    enum TYPE {
        NO_CRIMINAL_RECORD,
        MORE_EXPERIENCE,
        MORE_CREDIT_SCORE,
        NO_CRIMINAL_RECORD_AND_MORE_EXPERIENCE,
        MORE_EXPERIENCE_AND_MORE_CREDIT_SCORE,
        NO_CRIMINAL_RECORD_AND_MORE_CREDIT_SCORE,
        INVALID // should throw exception
    }

    boolean evaluate(Applicant applicant);
}

class EvaluatorBuilder {
    public static Evaluator build(Evaluator.TYPE type) throws InvalidEvaluation {


    }
}


Решение (за бонус поени):



import java.util.Scanner;

public class ApplicantEvaluationTest {
    public static void main (String [] args) {
        Scanner scanner = new Scanner(System.in);
        String name = scanner.nextLine();
        int creditScore = scanner.nextInt();
        int employmentYears = scanner.nextInt();
        boolean hasCriminalRecord = scanner.nextBoolean();
        int choice = scanner.nextInt();
        Applicant applicant = new Applicant(name, creditScore, employmentYears, hasCriminalRecord);
        Evaluator.TYPE type = Evaluator.TYPE.values()[choice];
        Evaluator evaluator = null;
        try {
            evaluator = EvaluatorBuilder.build(type);
            System.out.println("Applicant");
            System.out.println(applicant);
            System.out.println("Evaluation type: " + type.name());
            if (evaluator.evaluate(applicant)) {
                System.out.println("Applicant is ACCEPTED");
            } else {
                System.out.println("Applicant is REJECTED");
            }
        } catch (InvalidEvaluation invalidEvaluation) {
            System.out.println("Invalid evaluation");
        }
    }
}

class Applicant {
    private String name;
    private int creditScore;
    private int employmentYears;
    private boolean hasCriminalRecord;

    Applicant(String name, int creditScore, int employmentYears, boolean hasCriminalRecord) {
        this.name = name;
        this.creditScore = creditScore;
        this.employmentYears = employmentYears;
        this.hasCriminalRecord = hasCriminalRecord;
    }

    public String getName() {
        return name;
    }

    int getCreditScore() {
        return creditScore;
    }

    int getEmploymentYears() {
        return employmentYears;
    }

    boolean hasCriminalRecord() {
        return hasCriminalRecord;
    }

    @Override
    public String toString() {
        return String.format("Name: %s\nCredit score: %d\nExperience: %d\nCriminal record: %s\n",
                name, creditScore, employmentYears, hasCriminalRecord ? "Yes" : "No");
    }
}

interface Evaluator {
    enum TYPE {
        NO_CRIMINAL_RECORD,
        MORE_EXPERIENCE,
        MORE_CREDIT_SCORE,
        NO_CRIMINAL_RECORD_AND_MORE_EXPERIENCE,
        MORE_EXPERIENCE_AND_MORE_CREDIT_SCORE,
        NO_CRIMINAL_RECORD_AND_MORE_CREDIT_SCORE,
        INVALID
    }

    boolean evaluate(Applicant applicant);
}

class InvalidEvaluation extends Exception { }

class EvaluatorBuilder {
    static Evaluator build(Evaluator.TYPE type) throws InvalidEvaluation {
        switch (type) {
            case NO_CRIMINAL_RECORD: {
                return new CriminalRecord(null);
            }
            case MORE_EXPERIENCE: {
                return new Experience(null);
            }
            case MORE_CREDIT_SCORE: {
                return new CreditScore(null);
            }
            case NO_CRIMINAL_RECORD_AND_MORE_EXPERIENCE: {
                return new CriminalRecord(new Experience(null));
            }
            case NO_CRIMINAL_RECORD_AND_MORE_CREDIT_SCORE: {
                return new CriminalRecord(new CreditScore(null));
            }
            case MORE_EXPERIENCE_AND_MORE_CREDIT_SCORE: {
                return new Experience(new CreditScore(null));
            }
            default:
                throw new InvalidEvaluation();
        }
    }
}

abstract class ChainEvaluator implements Evaluator {
    private final Evaluator next;

    ChainEvaluator(Evaluator next) {
        this.next = next;
    }

    boolean hasNext() {
        return next != null;
    }

    @Override
    public boolean evaluate(Applicant applicant) {
        return next.evaluate(applicant);
    }
}

class CriminalRecord extends ChainEvaluator {

    CriminalRecord(Evaluator next) {
        super(next);
    }

    @Override
    public boolean evaluate(Applicant applicant) {
        if (applicant.hasCriminalRecord())
            return false;
        else if (this.hasNext())
            return super.evaluate(applicant);
        else
            return true;
    }
}

class Experience extends ChainEvaluator {

    Experience(Evaluator next) {
        super(next);
    }

    @Override
    public boolean evaluate(Applicant applicant) {
        if (applicant.getEmploymentYears() < 10)
            return false;
        else if (this.hasNext())
            return super.evaluate(applicant);
        else
            return true;
    }
}

class CreditScore extends ChainEvaluator {

    CreditScore(Evaluator next) {
        super(next);
    }

    @Override
    public boolean evaluate(Applicant applicant) {
        if (applicant.getCreditScore() < 500)
            return false;
        else if (this.hasNext())
            return super.evaluate(applicant);
        else
            return true;
    }
}