Question

在Eclipse中编译的员工电话程序，错误：

Exception in thread "main" java.lang.Error: Unresolved compilation problem: 
        at pcsettingfirstpj.Ch8_1_1.main(Employee.java:34)

与程序：

package pcsettingfirstpj;

public class Employee {
    private char name;
    private Phone list;
    class Phone {
        private long home, cell;
        public Phone(long phone1, long phone2){
            home = phone1;  cell = phone2;
        }
        public void printPhone(){
            System.out.println("Tel (Home 2): " + home);
            System.out.println("Tel (Mobile 2): " + cell);
        }
    }

    public Employee(char name, long home, long cell){
        this.name = name;
        list = new Phone(home, cell);
    }

    public void printEmployee(){
        System.out.println("====Staff====");
        System.out.println("Name: " + name);
        System.out.println("Tel (Home 1): " + list.home);
        System.out.println("Tel (Mobile 1): " + list.cell);
        list.printPhone();
    }
}

public class Ch8_1_1 {
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Employee joe = new Employee('a',28456789L, 936555552L);
        Employee jane = new Employee('b',23134563L,938444444L);
        joe.printEmployee();
        jane.printEmployee();
    }
}

Answer 1

您似乎已在单个文件中定义了多个公共类，这会导致编译错误，因为Java无法在同一文件中编译两个相邻的公共类。如果这是您的意图，则可以删除public修饰符以使其package-private。

将此文件命名为Ch8_1_1.java。

public class Ch8_1_1 {
    public static void main(String[] args) {
        Employee joe = new Employee('a', 28456789L, 936555552L);
        Employee jane = new Employee('b', 23134563L, 938444444L);
        joe.printEmployee();
        jane.printEmployee();
    }
}

class Employee {

    private char name;
    private Phone list;

    class Phone {
        private long home, cell;

        public Phone(long phone1, long phone2) {
            home = phone1;
            cell = phone2;
        }

        public void printPhone() {
            System.out.println("Tel (Home 2): " + home);
            System.out.println("Tel (Mobile 2): " + cell);
        }
    }

    public Employee(char name, long home, long cell) {
        this.name = name;
        list = new Phone(home, cell);
    }

    public void printEmployee() {
        System.out.println("====Staff====");
        System.out.println("Name: " + name);
        System.out.println("Tel (Home 1): " + list.home);
        System.out.println("Tel (Mobile 1): " + list.cell);
        list.printPhone();
    }
}

Answer 2

请尝试按照以下步骤操作：

将这两个类放在单独的文件中：Ch8_1_1.java和Employee.java可能在同一个包中。
使用IDE将类Ch8_1_1.java作为java应用程序运行。

问题是你在同一个file.java中有多个公共类

Answer 3

每当一个类被定义为公共类时，它应该在一个具有相同名称的文件中。

例如：公共类员工

FileName：Employee.java

在你的情况下，Employee是公共的，因此编译器希望它是Employee.java来生成Employee.class ..但是在同一个类中你还有一个公共类Ch8_1_1，所以它也想要文件名为Ch8_1_1.java以生成无法发生的Ch8_1_1.class ..

声明Employeee为class Employee而没有公开修饰符..

不要在同一个文件中声明两个公共类..

package pcsettingfirstpj;

class Employee {

private char name;
private Phone list;
class Phone {
    private long home, cell;
    public Phone(long phone1, long phone2){
        home = phone1;  cell = phone2;
    }
    public void printPhone(){
        System.out.println("Tel (Home 2): " + home);
        System.out.println("Tel (Mobile 2): " + cell);
    }
}

public Employee(char name, long home, long cell){
    this.name = name;
    list = new Phone(home, cell);
}

public void printEmployee(){
    System.out.println("====Staff====");
    System.out.println("Name: " + name);
    System.out.println("Tel (Home 1): " + list.home);
    System.out.println("Tel (Mobile 1): " + list.cell);
    list.printPhone();
}
}

public class Ch8_1_1 {

public static void main(String[] args) {
    // TODO Auto-generated method stub
    Employee joe = new Employee('a',28456789L, 936555552L);
    Employee jane = new Employee('b',23134563L,938444444L);
    joe.printEmployee();
    jane.printEmployee();
}

}

Eclipse Java员工电话程序

3 个答案: