这是我的ID程序，它存储名字，姓氏，出生日期和地点，电子邮件和电话号码。如何使用有效的出生日期，电子邮件和电话号码制作和存储人物对象（而不是拥有所有属性）？
这是我的主要身份识别计划：
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class ID {
static List<Oseba> id = new ArrayList<Oseba>();
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int max = 0;
int choice = 0;
boolean isDate = false;
String regEx_Email = "^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";
String regEx_Date = "(0?[1-9]|[12][0-9]|3[01])/(0?[1-9]|1[012])/((19|20)\\d\\d)";
System.out.println("How many IDs would you like to enter? ");
max = sc.nextInt();
System.out.println(" 0. Exit. ");
System.out.println(" 1. Add contact. ");
System.out.println(" 2. Outprint all contacts. ");
choice = sc.nextInt();
while (choice != 0) {
switch (choice) {
case 0:
System.out.println("Goodbye!");
System.exit(0);
case 1:
while (choice != 2) {
System.out.println("Enter First Name: ");
String firstName = sc.next();
System.out.println("Enter Last Name: ");
String lastName = sc.next();
System.out.println("Enter date of birth (dd-mm-yyyy): ");
String date = sc.next();
isDate = date.matches(regEx_Date);
System.out.println("Enter place of birth: ");
String place = sc.next();
System.out.println("Enter email: ");
String email = sc.next();
Pattern p = Pattern.compile(regEx_Email);
Matcher m = p.matcher(email);
if (m.find()) {
System.out.println(email + " is a valid email address.");
} else {
System.out.println(email + " is a invalid email address");
}
System.out.println("Enter phone number:");
String phone = sc.next();
addID(firstName, lastName, date, place, email, phone);
}
break;
case 2:
System.out.println("\n" + ID.id);
break;
default:
System.out.println("Try again.");
break;
}
System.out.println(" 0. Exit. ");
System.out.println(" 1. Add contact. ");
System.out.println(" 2. Outprint all contacts. ");
choice = sc.nextInt();
}
}
private static void addID(String firstName, String lastName, String date, String place, String email, String phone) {
Person p = new Person(firstName, lastName, date, place, email, phone);
id.add(p);
}
}
我的Person课程：
class Person {
String firstName;
String lastName;
String date;
String place;
String email;
String phone;
public Person(String firstName, String lastName, String date, String place, String email, String phone) {
this.firstName = firstName;
this.lastName = lastName;
this.date = date;
this.place = place;
this.email = email;
this.phone = phone;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getPlace() {
return place;
}
public void setPlace(String place) {
this.place = place;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getDate() {
return date;
}
public void setDate(String date) {
this.date = date;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
public String toString() {
return "First Name: " + firstName + "\n"
+ "Last Name: " + lastName + "\n"
+ "Date of birth: " + date + "\n"
+ "Place of birth: " + place + "\n"
+ "Email: " + email + "\n"
+ "Phone number: " + phone + "\n\n";
}
}
感谢您的帮助。
答案 0 :(得分：2)
最好的方法是将问题分解为较小的问题。例如，为了验证输入，您将不得不直接调用setter，而是创建一个方法来负责验证每个案例的输入。尝试在任何地方使用这种方法，因为低耦合和高内聚始终是一个要求！我将提供有关您的实现的示例，但是，有多种方法可以做到这一点。我也不会使用例外，因为我注意到你还在开始。
除此之外，为了使其工作，您应该在Person类中添加默认构造函数（值是预定义的）。
最后，尽管没有推荐使用多个while循环的方法，因为它会使代码更复杂，我使用它来向您展示如何确保您将获得正确的输入，例如，如果用户输入没有得到验证，然后程序将继续询问用户，直到它将获得正确的输入。另外，当用户犯了错误时，应该提供指示以引导他/她。 （这通常是在例外情况下完成的，在我们的例子中，虽然我们提供了简单的控制台打印）。
所以让我们看看：
public class ID {
static List<Oseba> id = new ArrayList<Oseba>();
\*we create the menu like that in order to avoid multiple lines repetitions *\
private static String menuOptions = "Menu:" + "\nExit - Insert 0"
+ "\nAdd contact - Insert 1" + "\nExit Outprint all contacts - Insert 2";
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int max = 0;
int choice = 0;
boolean isDate = false;
System.out.println("How many IDs would you like to enter? ");
max = sc.nextInt();
Person p = new Person();
while (true) {
print(menuOptions);
choice = sc.nextInt();
switch (choice) {
case 0:
System.out.println("Goodbye!");
System.exit(0);
case 1:
while(true){
String fname = getString("Enter First Name: ");
if(verifyName(fname)){
p.setFirstName(fname);
break;
}
}
while(true){
String lname = getString("Enter Last Name: ");
if(verifyName(lname)){
p.setLastName(lname);
break;
}
}
while(true){
String date = getString("Enter date of birth (dd-mm-yyyy): ");
if(verifyBirthDate(date)){
p.setDate(date);
break;
}
}
while(true){
String birthPlace = getString("Enter place of birth: ");
if(verifyBirthPlace(birthPlace)){
p.setPlace(birthPlace);
break;
}
}
while(true){
String email = getString("Enter email address: ");
if(verifyEmail(email)){
p.setEmail(email);
break;
}
}
while(true){
String phoneNumber = getString("Enter phone number: ");
if(verifyPhoneNumber(phoneNumber)){
p.setPhone(phoneNumber);
break;
}
}
addID(p);
break;
case 2:
System.out.println("\n" + ID.id);
break;
default:
System.out.println("Try again.");
break;
}
print(menuOptions);
choice = sc.nextInt();
}
}
private static void addID(Person prs) {
id.add(prs);
}
public static Boolean verifyName(String name) {
if(!name.matches("[a-zA-Z]+")){
print("\nERROR_MESSAGE:____________The first/last name should contain only letters, everything else is not valid!");
return false;
}else{
return true;
}
}
public static Boolean verifyBirthDate(String date) {
String regEx_Date = "(0?[1-9]|[12][0-9]|3[01])/(0?[1-9]|1[012])/((19|20)\\d\\d)";
if(!date.matches(regEx_Date)){
print("\nERROR_MESSAGE:____________The birth date is not valid!");
return false;
}else{
return true;
}
}
public static Boolean verifyBirthPlace(String birthPlace) {
if(!birthPlace.matches("[a-zA-Z]+")){
print("\nERROR_MESSAGE:____________The birth place is not valid!");
return false;
}else{
return true;
}
}
public static Boolean verifyEmail(String email) {
String regEx_Email = "^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";
Pattern p = Pattern.compile(regEx_Email);
Matcher m = p.matcher(email);
if(!m.find()){
print("\nERROR_MESSAGE:____________"+email+" is an invalid email address");
return false;
}else{
return true;
}
}
public static Boolean verifyPhoneNumber(String phoneNumber) {
if(!phoneNumber.matches("[0-9]+")){
print("\nERROR_MESSAGE:____________The phone No. should contain only numbers, everything else is not valid!");
return false;
}else{
return true;
}
}
public static String getString(String msg) {
Scanner in = new Scanner(System.in);
print(msg);
String s = in.nextLine();
return s;
}
public static void print(String s) {
System.out.println(s);
}
}
答案 1 :(得分：1)
创建一个像这样的构造函数
public Person(String date, String email, String phone) {
this.date = date;
this.email = email;
this.phone = phone;
}
您可以选择添加
this.firstName = null;
this.lastName = null;
//for all of your fields.
您还需要uodate getter和toString方法来检查字段是否已初始化。例如，对于你的getFirstName（）
if (firstName!=null)
return firstName;
return "";
答案 2 :(得分：1)
你听说过Primitive Obsession吗？
我会使用Date（JodaDate）代替String出生日期。
我会创建一个Email值对象，如果提供的IllegalArgumentException不是有效的电子邮件（由regexp验证），则抛出String。
我会创建一个Phone值对象，如果提供的IllegalArgumentException不是有效的电话号码，则会抛出String。
构造函数变为：
public Person(String firstName, String lastName, Date birthDate, String place, Email email, Phone phone)
例如，Email对象将是：
public class Email {
private String value;
public Email(String email) {
if(isNotValid(email))
throw new IllegalArgumentException("Your mail is not valid!");
this.value = email;
}
public final String getValue(){
return email;
}
private boolean isNotValid(){
//return false if email regexp validation is not verified
}
//....equals - hashcode if needed here
}
因此，您的Person始终是有效的人。
实际上，检查其组件是否有效是客户的责任，而不是Person的直接责任。通过阅读API，它为读者提供了Person所期望的信息。
答案 3 :(得分：1)
isDate字段的最佳名称是isValidDate。
你能使用简单的if语句：
if(isValidDate && m.find())
addID(firstName, lastName, date, place, email, phone);
或者您可以创建检查验证的方法：
private boolean isValidDate(String date){
if(number!=null && number!=""){
String regEx_Date = "(0?[1-9]|[12][0-9]|3[01])/(0?[1-9]|1[012])/((19|20)\\d\\d)";
return date.matches(regEx_Date);
}
return false;
}
答案 4 :(得分：0)
添加一个新的布尔变量以跟踪有效输入。如果所有输入都有效，则只将Person对象添加到ArrayList
boolean isValid=true;
if (m.find()) {
System.out.println(email + " is a valid email address.");
} else {
isValid=false;
System.out.println(email + " is a invalid email address");
}
if(isValid)
{
//Do other check phone number and valid birth date similarly
}
if(isValid)
{
addID(firstName, lastName, date, place, email, phone);
}