Java根据实体类的某一个属性进行排序

你的名字 2023-06-19 02:50 3阅读 0赞

# Java根据实体类的某一个属性进行排序 #

*  实体类

/**
     * 用户实体类
     */
    public class UserEntity {
    
        private int id;
    
        private String username;
    
        private String sex;
    
        private int age;
    
        private String address;
    
        public int getId() {
            return id;
        }
    
        public void setId(int id) {
            this.id = id;
        }
    
        public String getUsername() {
            return username;
        }
    
        public void setUsername(String username) {
            this.username = username;
        }
    
        public String getSex() {
            return sex;
        }
    
        public void setSex(String sex) {
            this.sex = sex;
        }
    
        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;
        }
    
        public UserEntity(int id, String username, String sex, int age, String address) {
            this.id = id;
            this.username = username;
            this.sex = sex;
            this.age = age;
            this.address = address;
        }
    
        @Override
        public String toString() {
            return "UserEntity{" +
                    "id=" + id +
                    ", username='" + username + '\'' +
                    ", sex='" + sex + '\'' +
                    ", age=" + age +
                    ", address='" + address + '\'' +
                    '}';
        }
    }

*  未排序

public static void main(String[] args) {
            UserEntity userEntity1 = new UserEntity(0, "张晓红","女",1 , "beijignshi");
            UserEntity userEntity2 = new UserEntity(1, "李晓红","女",1 , "tianjinshi");
            UserEntity userEntity3 = new UserEntity(3, "项羽","男",2 , "chuguo");
            UserEntity userEntity4 = new UserEntity(4, "刘邦","男",2 , "hanchao");
    
            List<UserEntity> list = new ArrayList<>();
            list.add(userEntity2);
            list.add(userEntity1);
            list.add(userEntity4);
            list.add(userEntity3);
    
            System.out.println(Objects.toString(list));
        }
        输出结果：
        	[UserEntity{id=1, username='李晓红', sex='女', age=1, address='tianjinshi'}, 
        	UserEntity{id=0, username='张晓红', sex='女', age=1, address='beijignshi'}, 
        	UserEntity{id=4, username='刘邦', sex='男', age=2, address='chuguo'}, 
        	UserEntity{id=3, username='项羽', sex='男', age=2, address='hanchao'}]

*  Collections排序后

public static List<UserEntity> sort(List<UserEntity> list){
            //根据指定比较器产生的顺序对指定列表进行排序。
            Collections.sort(list, new Comparator<UserEntity>() {
                @Override
                public int compare(UserEntity o1, UserEntity o2) {
                    //获取所需语言环境的 Collator，根据所需切换其他语言环境
                    //Collator collator = Collator.getInstance(Locale.ENGLISH);
                    //return collator.compare(o1.getAddress(), o2.getAddress());
                    Collator collator = Collator.getInstance(Locale.CANADA);
                    return collator.compare(o1.getUsername(), o2.getUsername());
                }
            });
            return list;
        }
    输出结果： 
    	[UserEntity{id=4, username='刘邦', sex='男', age=2, address='hanchao'}, 
    	UserEntity{id=0, username='张晓红', sex='女', age=1, address='beijignshi'}, 
    	UserEntity{id=1, username='李晓红', sex='女', age=1, address='tianjinshi'}, 
    	UserEntity{id=3, username='项羽', sex='男', age=2, address='chuguo'}]