클래스·참조 종합 실습

public class Member {
    String email;
    int age;
    boolean active;
}

Member[] members = new Member[3];
int size = 0;

int index = size;
size++;

Member member = createMember(email, age);
members[index] = member;

Member member = createMember(email, age);
members[size] = member;
size++;

System.out.print("회원 나이(세): ");
String rawAge = scanner.nextLine();
int age = Integer.parseInt(rawAge);

import java.util.Scanner;

public class MemberRegistryCli {
    private static final int CAPACITY = 3;

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Member[] members = new Member[CAPACITY];
        int size = 0;

        while (size < members.length) {
            System.out.println("\n[" + (size + 1) + "/" + members.length + "]");
            String email = readEmail(scanner);
            int age = readMemberAge(scanner);

            Member member = createMember(email, age, false);
            members[size] = member;
            size++;
        }

        printMembers(members, size);

        System.out.print("\n찾을 이메일: ");
        String keyword = scanner.nextLine().trim();
        Member found = findByEmail(members, size, keyword);
        printSearchResult(found);
    }

    static String readEmail(Scanner scanner) {
        while (true) {
            System.out.print("이메일: ");
            String email = scanner.nextLine().trim();
            if (!email.isEmpty()) {
                return email;
            }
            System.out.println("이메일은 비워 둘 수 없습니다.");
        }
    }

    static int readMemberAge(Scanner scanner) {
        while (true) {
            System.out.print("회원 나이(세): ");
            String input = scanner.nextLine().trim();
            try {
                int age = Integer.parseInt(input);
                if (age >= 14 && age <= 120) {
                    return age;
                }
                System.out.println("회원 나이는 14세 이상 120세 이하여야 합니다.");
            } catch (NumberFormatException exception) {
                System.out.println("정수를 입력해 주세요.");
            }
        }
    }

    static Member createMember(
        String email,
        int age,
        boolean active
    ) {
        if (email == null || email.isBlank() || age < 14 || age > 120) {
            throw new IllegalArgumentException("invalid member");
        }
        Member member = new Member();
        member.email = email;
        member.age = age;
        member.active = active;
        return member;
    }

    static void printMembers(Member[] members, int size) {
        System.out.println("\n== 회원 저장소 ==");
        for (int i = 0; i < size; i++) {
            Member member = members[i];
            System.out.printf(
                "%d. %s / %d세 / %s%n",
                i + 1,
                member.email,
                member.age,
                member.active ? "활성" : "비활성"
            );
        }
    }

    static Member findByEmail(
        Member[] members,
        int size,
        String email
    ) {
        for (int i = 0; i < size; i++) {
            Member member = members[i];
            if (member.email.equalsIgnoreCase(email)) {
                return member;
            }
        }
        return null;
    }

    static void printSearchResult(Member found) {
        if (found == null) {
            System.out.println("일치하는 회원이 없습니다.");
            return;
        }
        System.out.println(
            "검색 결과: " + found.email + " / " + found.age + "세"
        );
    }
}

javac -d out src/members/ch04/finalv/Member.java src/members/ch04/finalv/MemberRegistryCli.java
java -cp out MemberRegistryCli

[1/3]
이메일: [email protected]
회원 나이(세): 35

[2/3]
이메일: [email protected]
회원 나이(세): 삼십
정수를 입력해 주세요.
회원 나이(세): 30

[3/3]
이메일: [email protected]
회원 나이(세): 20

== 회원 저장소 ==
1. [email protected] / 35세 / 비활성
2. [email protected] / 30세 / 비활성
3. [email protected] / 20세 / 비활성

찾을 이메일: [email protected]
검색 결과: [email protected] / 30세

Member found = findByEmail(members, size, "[email protected]");
if (found != null) {
    found.active = true;
}
printMembers(members, size);