我正在皮尔逊我的编程实验室做作业，顺便说一句，我的程序没有结果。然而，在netbeans上，我的应用程序是可靠的，可以编译并提供所需的输出。我浏览了论坛，发现了一个类似的问题，但修复建议不适用于我的应用程序。
作业如下：
设计一个名为 Person 包含用于保存人员姓名、地址和电话号码的字段（全部为 String s） 是的。编写一个初始化所有这些值的构造函数，以及每个字段的mutator和accessor方法。
接下来，设计一个名为 Customer ，它继承自 Person 班级。这个 Customer 班级应该有一个 String 客户编号和 boolean 指示客户是否希望在邮件列表中的字段。编写一个构造函数来初始化这些值，并为类的字段编写相应的mutator和accessor方法。
演示 Customer 在程序中初始化，该程序提示用户输入客户的姓名、地址、电话号码和客户号码的值，然后询问用户该客户是否希望接收邮件。使用此信息创建客户对象，然后打印其信息。
将所有类放在同一个文件中。要做到这一点，不要把它们公开。相反，只需写下：

class  Person { ... }
class  Customer { ... }

提交以下代码后，我收到的错误是：

Driver.java:103: error: class Demo is public, should be declared in a file named Demo.java
     public class  Demo
            ^
1 error

代码：

import java.util.Scanner;

class Person

{

private String name;
private String address;
private String number;

public Person(String name, String address, String number)
{
        super();
        this.name = name;
        this.address = address;
        this.number = number;
}

    public String getName()
{
    return name;

}

public void setName(String name)
{
    this.name = name;

}

public String getAddress()

{
    return address;

}

public void setAddress(String a)

{
    address = a;

}

public String getNumber()
{
    return number;

}

public void setNumber(String number){
 this.number = number;
}

}

class Customer extends Person

{
 private String custNumber;
 private boolean wants;

 public Customer(String name, String address, String number, String         custNumber, boolean wants)
 {
  super(name, address, number);
  this.custNumber = custNumber;
  this.wants = wants;
 }

 public String getcustNumber()
 {
    return custNumber;

 }

 public boolean isWants()
 {
    return wants;
 }

 public void setWants(boolean wants)
 {
   this.wants = wants;
 }
}

/**
 *
 * @author Jonathan
 */

  public class  Tester
 {

   public static void main(String[] args)
   {
        String name, address, number;
        String custNumber;
        String decide;
        boolean wants;

        Scanner keyboard = new Scanner(System.in);

        System.out.print("Enter name of customer:Enter address of     customer:Enter phone number of customer:Enter yes/no -- does the customer want to recieve mail?:");

        name = keyboard.nextLine();

        address = keyboard.nextLine();

        number = keyboard.nextLine();

        custNumber = keyboard.nextLine();

        decide = keyboard.nextLine();
                    wants = decide.equals("yes");

        Customer one = new Customer(name, address, number, custNumber,     wants); // creates new Customer Object.
        System.out.println("Customer: ");
        System.out.println("Name: " + one.getName());
        System.out.println("Address: " + one.getAddress());
        System.out.println("Phone Number: " + one.getNumber());
        System.out.println("Receive Mail?: " + one.isWants());

   }

 }