Java函数式编程如何处理多执行流？

import java.util.Arrays;
import java.util.List;
import java.util.stream.Stream;

public class Main {

    public static void main(String[] args) {
        // 创建员工列表
        List<Employee> employees = Arrays.asList(
            new Employee("John Smith", 1000),
            new Employee("Jane Doe", 1500)
        );

        // 并行处理每个员工的工资
        Stream<Employee> parallelStream = employees.stream().parallel();
        Stream<Employee> doubledSalaries = parallelStream
            .map(e -> new Employee(e.getName(), e.getSalary() * 2));

        // 打印加倍后的工资
        doubledSalaries.forEach(System.out::println);
    }
}

class Employee {
    private String name;
    private double salary;

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

    // 省略 getters 和 setters
}

Employee(John Smith, 2000.0)
Employee(Jane Doe, 3000.0)