在 1 次输入后循环跳过我的扫描仪

Question

嘿，我正在尝试制作一个 phone 联系人项目，然后我开始创建一个 addContact() void，它在无限循环中接受 2 个输入名称和 phone 数字。我的问题是在名称输入后没有输入 phone 数字。你能帮我么？下面是我的代码

import java.util.*;

public class Problem {
private final Scanner scanner = new Scanner(System.in);
private final ArrayList<String> contactNames = new ArrayList<>();
private final ArrayList<Integer> contactNumbers = new ArrayList<>();
private final HashMap<String, Integer> contactMap = new HashMap<>();

public void addContact() {
    while (true) {
        System.out.println("Enter a phone number");
        int contactNumber = scanner.nextInt();
        if (contactNumbers.contains(contactNumber)) {
            System.out.println("This number is already given in your contacts");
            break;
        }
        System.out.println();
        System.out.println("Enter your contacts name");
        String name = scanner.nextLine();
        name = name.toLowerCase();
        if(contactNames.contains(name)){
            System.out.println("This name is already given in your contacts");
            break;
        }
        contactNumbers.add(contactNumber);
        contactNames.add(name);
        contactMap.put(name, contactNumber);
        System.out.println("Person is successfully added to your contacts, here is your all contacts below");
        System.out.println(contactMap);
        System.out.println("Do you want to quit?  -> 1=yes, 2=no");
        int quit = scanner.nextInt();
        if(quit==1)
            break;
    }
}

public static void main (String[] args){
    Problem a = new Problem();
    a.addContact();
}

}

Answer 1

解决方案

scanner.nextLine(); //add this line
System.out.println();
System.out.println("Enter your contacts name");

这是为了消除用户输入 phone 号码并按下回车键后创建的换行符。更多信息来自这里：Scanner is skipping nextLine() after using next() or nextFoo()?

在 1 次输入后循环跳过我的扫描仪

While loop skippping my Scanners after 1 input

java

loops

hashmap

while-loop

java.util.scanner