Question

所以在我的班上我们正在制作简单的程序，我们正在引入继承。我已经让一切正常工作，但我无法让这一点输出正常工作。当我要求输入时，它会跳过我的一个输入并转到第二个请求。当我在不需要之前评论所有其他事情时，它不会跳过第一个输入。我不明白为什么会这样，如果有人可以帮我解释为什么会受到高度赞赏。在此先感谢，这是我的两个课程，然后是测试人员：

人员类：

    public class Person{
    private String name, address, phoneNumber;
    public Person(){
        name="none";
        address="none";
        phoneNumber="none";
    }
    public Person(String inName, String inAddress, String inPhoneNumber){
        name=inName;
        address=inAddress;
        phoneNumber=inPhoneNumber;
    }
    public String getName(){
        return name;
    }
    public void setName(String newName){
        name = newName;
    }
    public String getAddress(){
        return address;
    }
    public void setAddress(String newAddress){
        address = newAddress;
    }
    public String getPhoneNumber(){
        return phoneNumber;
    }
    public void setPhoneNumber(String newPhoneNumber){
        phoneNumber = newPhoneNumber;
    }
    public String toString(){
        return String.format("Name: " + name + "\nAddress: " + address + "\nPhone Number: " + phoneNumber);
    }
    public void clearPerson(){
        name="none";
        address="none";
        phoneNumber="none";
    }
}

客户类：

    public class Customer extends Person{
    private int customerNumber;
    private boolean mailingList;
    public Customer(){
        customerNumber=0;
        mailingList=false;
    }
    public Customer(int inCustomerNumber, boolean inMailingList){
        customerNumber=inCustomerNumber;
        mailingList=inMailingList;
    }
    public int getCustomerNumber(){
        return customerNumber;
    }
    public void setCustomerNumber(int newCustomerNumber){
        customerNumber=newCustomerNumber;
    }
    public boolean getMailingList(){
        return mailingList;
    }
    public void setMailingList(boolean newMailingList){
        mailingList=newMailingList;
    }
    public String toString(){
        return "Customer Number: "+customerNumber+"\nMailing List: "+mailingList+"\n";
    }
    public void clearCustomer(){
        customerNumber=0;
        mailingList=false;
    }
}

测试员类：

import java.util.*;
public class CustomerPersonTester{
    public static void main(String[] args){
        Scanner in = new Scanner(System.in);
        Person testP1 = new Person();
        Customer testC1 = new Customer();
        System.out.println("Empty paramaters constructed on Person and Customer. Results: ");
        System.out.println(testP1.toString());
        System.out.println(testC1.toString());
        /*System.out.println(testP1.getName());
        System.out.println(testP1.getAddress());
        System.out.println(testP1.getPhoneNumber());
        System.out.println(testC1.getCustomerNumber());
        System.out.println(testC1.getMailingList());*/
        System.out.println("Expected: none x3, 0, false.\n");
        System.out.print("Enter a new name: ");
        String newName = in.nextLine();
        System.out.print("Enter a new address: ");
        String newAddress = in.nextLine();
        System.out.print("Enter a new phone number: ");
        String newPhoneNumber = in.nextLine();
        System.out.print("Enter a new customer number: ");
        int newCustomerNumber = in.nextInt();
        System.out.print("Enter a new true/false for mailing list: ");
        boolean newMailingList = in.nextBoolean();
        testP1.setName(newName);
        testP1.setAddress(newAddress);
        testP1.setPhoneNumber(newPhoneNumber);
        testC1.setCustomerNumber(newCustomerNumber);
        testC1.setMailingList(newMailingList);
        System.out.println(testP1.toString());
        System.out.println(testC1.toString());
        /*System.out.println(testP1.getName());
        System.out.println(testP1.getAddress());
        System.out.println(testP1.getPhoneNumber());
        System.out.println(testC1.getCustomerNumber());
        System.out.println(testC1.getMailingList());*/
        System.out.println("Expected: given name/address/phone number/customer number/boolean.\n");
        testP1.clearPerson();
        testC1.clearCustomer();
        System.out.println("\nTest 1 Complete. Values are reset. Please continue.\n");
        System.out.print("Enter a name: ");
        String inName = in.nextLine();
        System.out.print("Enter an address: ");
        String inAddress = in.nextLine();
        System.out.print("Enter a phone number: ");
        String inPhoneNumber = in.nextLine();
        System.out.print("Enter a customer number: ");
        int inCustomerNumber = in.nextInt();
        System.out.print("Enter true/false for mailing list: ");
        boolean inMailingList = in.nextBoolean();
        Person testP2 = new Person(inName, inAddress, inPhoneNumber);
        Customer testC2 = new Customer(inCustomerNumber, inMailingList);
        System.out.println(testP2.toString());
        System.out.println(testC2.toString());
        /*System.out.println(testP2.getName());
        System.out.println(testP2.getAddress());
        System.out.println(testP2.getPhoneNumber());
        System.out.println(testC2.getCustomerNumber());
        System.out.println(testC2.getMailingList());*/
        System.out.println("Expected: given name/address/phone number/customer number/boolean.\n");
        System.out.println("Program complete. Terminating...");
        in.close();
    }
}

我的输出看起来像这样：

Empty paramaters constructed on Person and Customer. Results: 
Name: none
Address: none
Phone Number: none
Customer Number: 0
Mailing List: false

Expected: none x3, 0, false.

Enter a new name: Bob
Enter a new address: 123 Happy Lane
Enter a new phone number: 123-456-7890
Enter a new customer number: 12
Enter a new true/false for mailing list: true
Name: Bob
Address: 123 Happy Lane
Phone Number: 123-456-7890
Customer Number: 12
Mailing List: true

Expected: given name/address/phone number/customer number/boolean.


Test 1 Complete. Values are reset. Please continue.

Enter a name: Enter an address: Problem starts here...

Answer 1

对nextBoolean() 的调用不会使用true或false输入后面的换行符。因此，当您下次调用nextLine()时，此换行符仍然在输入缓冲区中，它会立即使用剩余的换行符然后继续。

要获得预期的行为，只需在致电nextLine()后再向nextBoolean()添加另一个电话即可。您还应该注意，如果nextInt()也是序列中的最后一次调用，则会发生这种情况。

您可能还想考虑将部分代码放入某种形式的循环（也许是一个while循环？），这样就不会有大量的重复代码。

简单的输出问题

1 个答案: