Collectors.partitioningList を 2 つのコレクションに分解するために使用します。

package com.xxx.xx.xx;

import com.alibaba.fastjson.JSON;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

public class TestDemo {
    
    
    public static void main(String[] args) {
    
    
        List<Student> list = new ArrayList<>();
        Student student1 = new Student("张三", "踢球");
        Student student2 = new Student("李四", "滑雪");
        Student student3 = new Student("王五", "看电视");
        Student student4 = new Student("赵六", "踢球");
        list.add(student1);
        list.add(student2);
        list.add(student3);
        list.add(student4);
        Map<Boolean, List<Student>> collect = list.stream().collect(Collectors.partitioningBy(st -> st.getHobby() == "踢球"));
        System.out.println(JSON.toJSONString(collect));
    }

    static class Student {
    
    
        private String hobby;
        private String name;

        public Student(String name, String hobby) {
    
    
            this.hobby = hobby;
            this.name = name;
        }

        public String getHobby() {
    
    
            return hobby;
        }

        public void setHobby(String hobby) {
    
    
            this.hobby = hobby;
        }

        public String getName() {
    
    
            return name;
        }

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

結果：

{
    
    false:[{
    
    "hobby":"滑雪","name":"李四"},{
    
    "hobby":"看电视","name":"王五"}],true:[{
    
    "hobby":"踢球","name":"张三"},{
    
    "hobby":"踢球","name":"赵六"}]}