该程序应包含客户以及一周中的卡路里和距离的列表。
我的问题是，如何将客户的姓名和距离汇总在一起？
public class TestCustomer {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
ArrayList<String> customersNames = new ArrayList<String>();
char userInput = ' ';
System.out.println("A to show all");
userInput = scan.next().charAt(0);
if(userInput == 'A') {
System.out.println("All results ");
for(int i = 0; i < customersNames.size(); i++) {
System.out.println(customersNames.get(i));
}
}
}
这是我的客户课程
public class Customer {
private String name;
private double calories;
private double distance;
public Customer(String name, double distance) {
this.name = name;
this.distance = distance;
}
public void setName(String name) {
this.name = name;
}
public String getName() {
return name;
}
public void setCalories(double calories) {
this.calories = calories;
}
public double getCalories() {
return calories;
}
public void setDistance(double distance) {
this.distance = distance;
}
public double getDistance() {
return distance;
}
}
答案 0 :(得分：0)
这使用客户列表而不是客户名称。 为了简洁起见，我将Customer类作为静态放在testclass中（将所有内容保存在一个文件中）。最好像您一样将其分开。
我也不希望更改整个设计或进行完整的重写-这是您的设计。因此，这只是使它起作用，将行为固定为所需的行为。
例如，在HashMap中具有按名称索引的客户，可以在O（1）中更优雅地检索数据集。但这也许是另一种改进。
这只有列表。因此，为简单起见，我添加了一个equals，如果用户具有相同的名称，则使用户平等。
我创建了一个可以在列表中搜索的新用户。如果未找到，则将具有给定输入的该用户添加到列表中。 如果找到，我将使用indexOf在列表中搜索现有用户并检索该现有用户。我一步就能做到。
import java.util.ArrayList;
import java.util.Objects;
import java.util.Scanner;
public class TestCustomer {
public static class Customer {
private String name;
private double calories;
private double distance;
public Customer(String name, double calories, double distance) {
this.name = name;
this.calories = calories;
this.distance = distance;
}
public void setName(String name) {
this.name = name;
}
public String getName() {
return name;
}
public void setCalories(double calories) {
this.calories = calories;
}
public double getCalories() {
return calories;
}
public void setDistance(double distance) {
this.distance = distance;
}
public double getDistance() {
return this.distance;
}
@Override
public int hashCode() {
int hash = 5;
hash = 71 * hash + Objects.hashCode(this.name);
return hash;
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
return Objects.equals(this.name, ((Customer)obj).name);
}
}
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
ArrayList<Customer> customers = new ArrayList<>();
char userInput = ' ';
while (userInput != 'q') {
System.out.println("Press 'a' to show all customers or press 's' to search for customer ");
userInput = scan.next().charAt(0);
userInput = Character.toUpperCase(userInput);
if (userInput == 'A') {
System.out.println("Here's the list of all customers: ");
for (int i = 0; i < customers.size(); i++) {
System.out.println(customers.get(i).getName());
}
// here I should show the list of all customers and their data
} else if (userInput == 'S') {
System.out.println("You selected to search for a customer");
createCustomer(customers);
}
}
}
public static ArrayList<Customer> createCustomer(ArrayList<Customer> customers) {
Scanner scan2 = new Scanner(System.in);
System.out.println("Enter customer's first name: ");
String fName = scan2.next();
System.out.println("Enter customer's last name: ");
String lName = scan2.next();
String fullName = fName + " " + lName;
Customer newCustomer = new Customer(fullName,0,0);
if (customers.contains(newCustomer)) {
newCustomer=customers.get(customers.indexOf(newCustomer));
System.out.println("Customer already on the list. Here's the information: ");
System.out.println(fullName + " " + newCustomer.distance + " " + newCustomer.calories );
} else{
System.out.println("Customer not found. Would you like to create a new customer? y/n ");
char createUserPrompt = scan2.next().charAt(0);
if (createUserPrompt == 'y') {
String[] daysOfWeek = {"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"};
for (String daysOfWeek1 : daysOfWeek) {
System.out.println("Enter calories consumed on " + daysOfWeek1);
newCustomer.calories = scan2.nextDouble();
System.out.println("Enter distance walked on " + daysOfWeek1);
newCustomer.distance = scan2.nextDouble();
}
customers.add(newCustomer);
} else if (createUserPrompt == 'n') {
System.out.println("User will not be added.");
}
}
return customers;
}
}
样品运行：
Press 'a' to show all customers or press 's' to search for customer
a
Here's the list of all customers:
Press 'a' to show all customers or press 's' to search for customer
s
You selected to search for a customer
Enter customer's first name:
kai
Enter customer's last name:
last
Customer not found. Would you like to create a new customer? y/n
y
Enter calories consumed on Monday
5
Enter distance walked on Monday
5
Enter calories consumed on Tuesday
5
Enter distance walked on Tuesday
5
Enter calories consumed on Wednesday
5
Enter distance walked on Wednesday
5
Enter calories consumed on Thursday
5
Enter distance walked on Thursday
5
Enter calories consumed on Friday
5
Enter distance walked on Friday
5
Enter calories consumed on Saturday
5
Enter distance walked on Saturday
5
Enter calories consumed on Sunday
5
Enter distance walked on Sunday
5
Press 'a' to show all customers or press 's' to search for customer
a
Here's the list of all customers:
kai last
Press 'a' to show all customers or press 's' to search for customer
s
You selected to search for a customer
Enter customer's first name:
kai
Enter customer's last name:
last
Customer already on the list. Here's the information:
kai last 5.0 5.0
Press 'a' to show all customers or press 's' to search for customer
答案 1 :(得分：0)
对您的Customer类进行了一些修改，将calories和distance每天存储在数组中，
ArrayList<Customer>将用于存储客户列表。
可能的解决方案：
import java.util.*;
public class Main {
private static Scanner scan;
private static ArrayList<Customer> customers;
public static Customer customerExists(String customerName) {
for (int i = 0; i < customers.size(); i++) {
if (customers.get(i).getName().equals(customerName)) {
return customers.get(i);
}
}
return null;
}
public static void addCustomer() {
System.out.println(">> Add Customer <<\n");
System.out.print("Enter customer's first name: ");
String fName = scan.nextLine();
System.out.print("Enter customer's last name: ");
String lName = scan.nextLine();
String fullName = fName + " " + lName;
Customer existingCustomer = customerExists(fullName);
if (existingCustomer != null) {
System.out.println("\nCustomer already on the list. Here's the information: ");
System.out.println("#\tName\t\tCalories [Mon-Sun]\t\t\t\t\t\tDistance [Mon-Sun]");
System.out.println(existingCustomer.getName() + "\t" + Arrays.toString(existingCustomer.getCalories()) + "\t" + Arrays.toString(existingCustomer.getDistance()));
return;
}
String[] daysOfWeek = {"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"};
double calories[] = new double[daysOfWeek.length];
double distance[] = new double[daysOfWeek.length];
for (int j = 0; j < daysOfWeek.length; j++) {
System.out.print("Enter calories consumed on " + daysOfWeek[j] + ": ");
calories[j] = scan.nextDouble();
System.out.print("Enter distance walked on " + daysOfWeek[j] + ": ");
distance[j] = scan.nextDouble();
}
Customer customer = new Customer(fullName, calories, distance);
customers.add(customer);
System.out.println("\nCustomer added successfully!\n");
}
public static void showCustomers() {
System.out.println(">> All Customers <<\n");
System.out.println("#\tName\t\tCalories [Mon-Sun]\t\t\t\t\t\tDistance [Mon-Sun]");
for (int i = 0; i < customers.size(); i++) {
System.out.println(i+1 + "\t" + customers.get(i).getName() + "\t" + Arrays.toString(customers.get(i).getCalories()) + "\t\t\t" + Arrays.toString(customers.get(i).getDistance()));
}
System.out.println("\n");
}
public static void searchCustomers() {
System.out.println(">> Search for a Customer <<\n");
System.out.print("Enter customer's full name: ");
String fullName = scan.nextLine();
Customer customer = customerExists(fullName);
System.out.println(fullName);
if (customer == null) {
System.out.println("\nNo such customer exists.\n");
return;
}
System.out.println("\nCustomer information:\n");
System.out.println("#\tName\t\tCalories [Mon-Sun]\t\t\t\t\t\tDistance [Mon-Sun]");
System.out.println(customer.getName() + "\t" + Arrays.toString(customer.getCalories()) + "\t" + Arrays.toString(customer.getDistance()) + "\n");
}
public static void main(String[] args) {
boolean cont = true;
int option = -1;
scan = new Scanner(System.in);
customers = new ArrayList<>();
do {
System.out.println("=== Select an Option ===");
System.out.println("1. Add a customer");
System.out.println("2. Show all customers");
System.out.println("3. Search for customer");
System.out.println("0. Exit");
System.out.print("\n > ");
try {
option = Integer.parseInt(scan.nextLine());
System.out.println("\n");
switch(option) {
case 1:
addCustomer();
break;
case 2:
showCustomers();
break;
case 3:
searchCustomers();
break;
case 0:
System.out.println("Good Bye!");
cont = false;
break;
default:
System.err.println("'" + option + "' is not a valid option. Please try again.\n");
break;
}
} catch (NumberFormatException e) {
System.err.println("Invalid option selected.\n");
}
} while (cont == true);
}
}