如何在 Java Streams Collectors Grouping 中添加指定过滤器

Question

我可以将名称、性别分组有没有办法我可以在此处使用过滤器，例如性别 'Male' 仅

我的密码是

List<Employee> employeesList = new ArrayList<>();

employeesList.add(new Employee(101, "Glady", "Manager", "Male", 25_00_000));
employeesList.add(new Employee(102, "Vlad", "Software Engineer", "Female", 15_00_000));
employeesList.add(new Employee(103, "Shine", "Lead Engineer", "Female", 20_00_000));
employeesList.add(new Employee(104, "Nike", "Manager", "Female", 25_00_000));
employeesList.add(new Employee(105, "Slagan", "Software Engineer", "Male", 15_00_000));
employeesList.add(new Employee(106, "Murekan", "Software Engineer", "Male", 15_00_000));
employeesList.add(new Employee(107, "Gagy", "Software Engineer", "Male", 15_00_000));



Map<String, Map<String, Long>> multipleFieldsMap = employeesList.stream()
        .collect(
                Collectors.groupingBy(Employee::getDesignation, 
                        Collectors.groupingBy(Employee::getGender, 
                                Collectors.counting())));

Answer 1

employeesList.stream()
             .filter(employee -> employee.getGender().equals("Male"))
             .collect( ... );

你可以使用 Stream 的 filter.

如何在 Java Streams Collectors Grouping 中添加指定过滤器

How to add specified filters in Java Streams Collectors Grouping

java

arrays

collections

java-stream