jdk1.8 list 多条件排序

拼搏现实的明天。 2022-10-24 01:36 191阅读 0赞

public class Student {
    
        private int No;
    
        private String name;
    
        private int age;
    
        private String address;
    
        public int getNo() {
            return No;
        }
    
        public void setNo(int no) {
            No = no;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public int getAge() {
            return age;
        }
    
        public void setAge(int age) {
            this.age = age;
        }
    
        public String getAddress() {
            return address;
        }
    
        public void setAddress(String address) {
            this.address = address;
        }
    
        @Override
        public String toString() {
            return "Student{" +
                    "No=" + No +
                    ", name='" + name + '\'' +
                    ", age=" + age +
                    ", address='" + address + '\'' +
                    '}';
        }
    
    }

public class Test {
    
        public static void main(String[] args) {
            Student s1 = new Student();
            s1.setNo(1);
            s1.setName("张三丰");
            s1.setAge(18);
            s1.setAddress("北京");
            Student s2 = new Student();
            s2.setNo(2);
            s2.setName("刘能");
            s2.setAge(18);
            s2.setAddress("天津");
            Student s3 = new Student();
            s3.setNo(3);
            s3.setName("王五");
            s3.setAge(17);
            s3.setAddress("上海");
            Student s4 = new Student();
            s4.setNo(4);
            s4.setName("赵六");
            s4.setAge(16);
            s4.setAddress("深圳");
            List<Student> list = new ArrayList<>();
            list.add(s1);
            list.add(s2);
            list.add(s3);
            list.add(s4);
    
            //age 正序
            Comparator<Student> byAgeAsc = Comparator.comparing(Student::getAge);
            //No 倒叙
            Comparator<Student> byNoDesc = Comparator.comparing(Student::getNo).reversed();
            //name 正序
            Comparator<Student> byName = Comparator.comparing(Student::getName);
            //联合排序
            Comparator<Student> finalComparator = byAgeAsc.thenComparing(byNoDesc).thenComparing(byName);
            List<Student> collect = list.stream().sorted(finalComparator).collect(Collectors.toList());
    
            System.out.println("多条件排序：" + collect);
            System.out.println("------排序结果：按照自定义排序");
    
            List<Student> collect1 = list.stream().sorted(Comparator.comparing(Student::getAge).thenComparing(Student::getNo)).collect(Collectors.toList());
            System.out.println("正序：" + collect1);
            System.out.println("------排序结果：age 正序，No 正序");
            List<Student> collect2 = list.stream().sorted(Comparator.comparing(Student::getAge).thenComparing(Student::getNo).reversed()).collect(Collectors.toList());
            System.out.println("整体结果倒叙返回：" + collect2);
            System.out.println("------排序结果：根据age 正序，No 正序的整体排序结果，倒叙返回。需要注意：返回结果不是age 正序，No 倒叙");
        }
    
    }

排序结果：
    多条件排序：[Student{No=4, name='赵六', age=16, address='深圳'}, Student{No=3, name='王五', age=17, address='上海'}, Student{No=2, name='刘能', age=18, address='天津'}, Student{No=1, name='张三丰', age=18, address='北京'}]
    ------排序结果：按照自定义排序
    正序：[Student{No=4, name='赵六', age=16, address='深圳'}, Student{No=3, name='王五', age=17, address='上海'}, Student{No=1, name='张三丰', age=18, address='北京'}, Student{No=2, name='刘能', age=18, address='天津'}]
    ------排序结果：age 正序，No 正序
    整体结果倒叙返回：[Student{No=2, name='刘能', age=18, address='天津'}, Student{No=1, name='张三丰', age=18, address='北京'}, Student{No=3, name='王五', age=17, address='上海'}, Student{No=4, name='赵六', age=16, address='深圳'}]
    ------排序结果：根据age 正序，No 正序的整体排序结果，倒叙返回。需要注意：返回结果不是age 正序，No 倒叙