Java 按薪资排序：比较器没有显示错误，但不起作用

请帮我理解，我错过了什么。 我需要按工资对我的员工进行分类。试图通过比较器来实现。显示无错误，但对输出没有影响

public class FirstActivity {

public static void main(String[] args) {

    //collection of employee
    Employee e1 = new Employee(1, "TestLead", "Microsoft", 4000.00, "Peter", "Doe", 35);
    Employee e2 = new Employee(2, "ManualTester", "Accenture", 1800.00, "Carl", "Fox", 56);
    Employee e3 = new Employee(3, "Developer", "IBM", 2100.00, "Michele", "Gilmore", 34);
    Employee e4 = new Employee(4, "Manager", "IBM", 2500.00, "Alfred", "Pink", 23);
    Employee e5 = new Employee(5, "AutomationTester", "Accenture", 2600.00, "Sam", "Bow", 40);
    
    // Initialise ArrayList
    List<Employee> employeeList = new ArrayList<Employee>();
    // add values
    employeeList.add(e1);
    employeeList.add(e2);
    employeeList.add(e3);
    employeeList.add(e4);
    employeeList.add(e5);
    
    
    // print values
    System.out.println("Workers salaries: ");

    Iterator<Employee> itr = employeeList.iterator();  
    //traverse elements of ArrayList object  
        while(itr.hasNext())
        {  
            Employee st=(Employee)itr.next();  
            System.out.println("Employees " + st.firstName + " salary is "+st.salary);
        }
        // trying to SORT by salary through this line
      employeeList.sort(Comparator.comparing(Employee::getSalary));
}
}

---

你的代码正在运行。您所做的不正确的事情是您正在打印列表，或者您需要在排序和比较器使用后再次打印列表

// trying to SORT by salary through this line
  employeeList.sort(Comparator.comparing(Employee::getSalary));
  employeeList.forEach(employee -> System.out.println("Employees " + employee.firstName + " salary is "+employee.salary));

查看我测试过的代码：

您的代码看起来不错。 我已经试过你的代码，它工作得很好。 排序后，您需要打印详细信息。 我试过下面的方法

public class FirstActivity {
    public static void main(String[] args) {

        // collection of employee
        Employee e1 = new Employee(1, "TestLead", "Microsoft", 4000.00, "Peter", "Doe", 35);
        Employee e2 = new Employee(2, "ManualTester", "Accenture", 1800.00, "Carl", "Fox", 56);
        Employee e3 = new Employee(3, "Developer", "IBM", 2100.00, "Michele", "Gilmore", 34);
        Employee e4 = new Employee(4, "Manager", "IBM", 2500.00, "Alfred", "Pink", 23);
        Employee e5 = new Employee(5, "AutomationTester", "Accenture", 2600.00, "Sam", "Bow", 40);

        // Initialise ArrayList
        List<Employee> employeeList = new ArrayList<>();
        // add values
        employeeList.add(e1);
        employeeList.add(e2);
        employeeList.add(e3);
        employeeList.add(e4);
        employeeList.add(e5);

        // print values
        System.out.println("Workers salaries before sorting: ");

        Iterator<Employee> itr = employeeList.iterator();
        // traverse elements of ArrayList object
        while (itr.hasNext()) {
            Employee st = (Employee) itr.next();
            System.out.println("Employees " + st.firstName + " salary is "+st.salary);
        }
        // trying to SORT by salary through this line
        employeeList.sort(Comparator.comparing(Employee::getSalary));

        System.out.println("\nWorkers salaries after sorting: ");
        Iterator<Employee> itr1 = employeeList.iterator();
        // traverse elements of ArrayList object
        while (itr1.hasNext()) {
            Employee st = (Employee) itr1.next();
            System.out.println("Employees " + st.firstName + " salary is "+st.salary);
        }
    }
}

---

这与javascript中的排序不同，排序列表是从调用中返回的。对不起，您所说的调用是什么意思？不幸的是，我的排序输出没有变量。有什么建议吗？谢谢。方法“sort”返回一个列表，所以如果你想要排序的列表，你必须将返回的值赋给一个变量，可能是同一个实例。您想在哪里打印已排序的列表？上面的代码以对sort的调用返回nothing结束，该调用上面的任何输出都不可能受到影响。在sort再次打印列表后，您将看到更改！对输出没有影响为什么输出后执行的排序会影响输出？非常感谢您的帮助！非常感谢你的建议！我很感激！这是我的荣幸。

Workers salaries before sorting: 
Employees TestLead salary is 4000.0
Employees ManualTester salary is 1800.0
Employees Developer salary is 2100.0
Employees Manager salary is 2500.0
Employees AutomationTester salary is 2600.0

Workers salaries after sorting: 
Employees ManualTester salary is 1800.0
Employees Developer salary is 2100.0
Employees Manager salary is 2500.0
Employees AutomationTester salary is 2600.0
Employees TestLead salary is 4000.0