（1）定义员⼯类Employee，包含属性员⼯ID、员⼯的姓名name，员⼯的⼯资salary （2）在（1）的基础上，完成相关的构造⽅法、相关属性的 set/get ⽅法，并⾃定义⽅法 toString，⽤于打印输出内部属性的值 （3）⾃拟数据，创建10个Employee对象，放⼊ArrayList中

好的，以下是根据你的要求定义的Employee类：

public class Employee {
    private int employeeID;
    private String name;
    private double salary;

    public Employee(int employeeID, String name, double salary) {
        this.employeeID = employeeID;
        this.name = name;
        this.salary = salary;
    }

    public int getEmployeeID() {
        return employeeID;
    }

    public void setEmployeeID(int employeeID) {
        this.employeeID = employeeID;
    }

    public String getName() {
        return name;
    }

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

    public double getSalary() {
        return salary;
    }

    public void setSalary(double salary) {
        this.salary = salary;
    }

    @Override
    public String toString() {
        return "Employee{" +
                "employeeID=" + employeeID +
                ", name='" + name + '\'' +
                ", salary=" + salary +
                '}';
    }
}

接下来，我们可以创建10个Employee对象，并将其放入ArrayList中：

import java.util.ArrayList;

public class Main {
    public static void main(String[] args) {
        ArrayList<Employee> employees = new ArrayList<>();

        employees.add(new Employee(1, "John", 5000));
        employees.add(new Employee(2, "Alice", 6000));
        employees.add(new Employee(3, "Bob", 5500));
        employees.add(new Employee(4, "Emily", 7000));
        employees.add(new Employee(5, "David", 4500));
        employees.add(new Employee(6, "Sarah", 8000));
        employees.add(new Employee(7, "Michael", 6500));
        employees.add(new Employee(8, "Jessica", 5500));
        employees.add(new Employee(9, "Daniel", 7500));
        employees.add(new Employee(10, "Olivia", 6000));

        for (Employee employee : employees) {
            System.out.println(employee.toString());
        }
    }
}

以上代码会创建10个Employee对象，并将其打印输出。

请注意，这只是一个示例，你可以根据自己的需求进行适当的修改。