자바 소스 해석좀 해주세요..

게시물 수정 , 삭제는 로그인 필요

학교 숙제 때문에 그러는데요, 자바 소스 코드하고 답이 있는데 이해를 못하겠네요; 소스 해석좀 해주세요.

 

문제 : 다음 PersonMain 클래스는 Person형 데이터와 Customer형 데이터를 people 배열에 저장하여 제공하고 출력하는 클래스이다. Person 클래스와 Customer 클래스를 만들어 보자.

- Person 클래스 : 이름, 주민등록번호, 주소 속성을 가진 클래스.

- Customer 클래스 : Person 클래스를 상속 받아 이름, 주민등록번호, 주소, 아이디, 패스워드를 가진 고객 클래스.

 

public class PersonMainTest{

            private Person[] people = new Person[5];

            private int index = 0;

 

            public void add(Person person){

                          people[index++] = person;

            }

 

            public Person[] list(){

                        return people;

            }

            public static void main(String[] args){

                        PersonMainTest pm = new PersonMainTest();

                        Person p = new Person();

                        p.setName("홍길동");

                        p.setJumin("111111-1111111");

                        p.setAddress("용산구");

                        pm.add(p);

                        Customer c = new Customer();

                        c.setId("sunrin");

                        c.setPasswd("123456");

                        c.setName("고주몽");

                        c.setJumin("222222-2222222");

                        c.setAddress("강남구");

                        pm.add(c);

 

                        c = new Customer("moon", "1234");

                        pm.add(c);

 

                        c = new Customer("a", "b", "c", "d", "e");

                        pm.add(c);

 

                        Person[] people = pm.list();

                        System.out.println("*** Data List ***");

                        for( int i = 0; i < people.length; i++)

                        System.out.println(people[i]);

            }

}

 

<실행결과>

Person Constructor

Person Constructor

Customer Constructor

Person Constructor

Person Constructor

*** Data List ***

Person : 홍길동

Customer : sunrin : 고주몽

Customer : moon : null

Customer : a : c

null

 

<해답>

1) Person.java

public class Person

{

            protected String name;

            protected String jumin;

            protected String address;

            public Person(){

                        System.out.println("Person Constructor");

            }

            public void setName(String name){

                        this.name = name;

            }

            public String getName(){

                        return name;

            }

            public void setJumin(String jumin){

                        if(jumin == null || jumin.equals("")){

                                    System.out.println("주민번호를 입력바람");

                                    return;

                        }

                        this.jumin=jumin;

            }

            public String getJumin(){

                        return jumin;

            }

            public void setAddress(String address){

                        this.address = address;

            }

            public String getAddress(){

                        return address;

            }

            public String toString(){

                        return "Person : " + name;

            }

}

 

2) Customer.java

public class Customer extends Person{

            private String id;

            private String passwd;

 

            public Customer(){

                        this("","");

                        System.out.println("Customer Constructor");

            }

            public Customer(String id, String passwd){

                        setId(id);

                        setPasswd(passwd);

            }

            public Customer(String id, String passwd, String name, String jumin, String address){

                        setId(id);

                        setPasswd(passwd);

                        setName(name);

                        setJumin(jumin);

                        setAddress(address);

            }

            public void setId(String id){

                        this.id = id;

            }

            public String getId(){

                        return id;

            }

            public void setPasswd(String passwd){

                        this.passwd = passwd;

            }

            public String getPasswd(){

                        return passwd;

            }

            public String toString(){

                        return "Customer :" + id + ":" + name;

            }

}

 

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여기까지 입니다 -_-;

 

문제 소스 해석은 필요 없구요, 해답 소스 해석만 해주세요.

 

각각 줄마다 주석 달아주시면 감사하겠습니다. 급한데 제발 빨리 해주세요 ㅠㅠ 부탁입니다.