（企业 / 公司项目）SpringBoot实现雪花算法id注册功能

叁歲伎倆 2024-04-29 19:03 53阅读 0赞

以下是使用 Spring Boot 实现雪花算法的完整代码。

import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class SnowflakeGeneratorApplication {
    
        public static void main(String[] args) {
            SpringApplication.run(SnowflakeGeneratorApplication.class, args);
        }
    
    }

import org.springframework.stereotype.Component;
    
    @Component
    public class SnowflakeGenerator {
        
        private final long START_STMP = 1480166465631L;
     
        // 每部分占用的位数，注意不能超过63位，即 long 类型的最大位数
        private final long SEQUENCE_BIT = 12; // 序列号占用的位数
        private final long MACHINE_BIT = 5; // 机器标识占用的位数
        private final long DATACENTER_BIT = 5;// 数据中心占用的位数
     
        // 每部分最大值
        private final long MAX_DATACENTER_NUM = -1L ^ (-1L << DATACENTER_BIT);
        private final long MAX_MACHINE_NUM = -1L ^ (-1L << MACHINE_BIT);
        private final long MAX_SEQUENCE = -1L ^ (-1L << SEQUENCE_BIT);
     
        // 每部分向左的位移
        private final long MACHINE_LEFT = SEQUENCE_BIT;
        private final long DATACENTER_LEFT = SEQUENCE_BIT + MACHINE_BIT;
        private final long TIMESTMP_LEFT = DATACENTER_LEFT + DATACENTER_BIT;
     
        private long datacenterId; // 数据中心
        private long machineId; // 机器标识
        private long sequence = 0L; // 序列号
        private long lastStmp = -1L; // 上一次时间戳
     
        public SnowflakeGenerator() {
            this.datacenterId = getDatacenterId(MAX_DATACENTER_NUM);
            this.machineId = getMachineId(MAX_MACHINE_NUM);
        }
     
        public synchronized long nextId() {
            long currStmp = getNewstmp();
     
            if (currStmp < lastStmp) {
                throw new RuntimeException("Clock moved backwards.  Refusing to generate id");
            }
     
            if (currStmp == lastStmp) {
                sequence = (sequence + 1) & MAX_SEQUENCE;
                if (sequence == 0L) {
                    currStmp = getNextMill();
                }
            } else {
                sequence = 0L;
            }
     
            lastStmp = currStmp;
     
            return (currStmp - START_STMP) << TIMESTMP_LEFT //
                    | datacenterId << DATACENTER_LEFT // 数据中心部分
                    | machineId << MACHINE_LEFT // 机器标识部分
                    | sequence; // 序列号部分
        }
     
        private long getNextMill() {
            long mill = getNewstmp();
            while (mill <= lastStmp) {
                mill = getNewstmp();
            }
            return mill;
        }
     
        private long getNewstmp() {
            return System.currentTimeMillis();
        }
     
        /**
         * 获取 maxDatacenterId
         */
        protected long getDatacenterId(long maxDatacenterId) {
            long id = 0L;
            try {
                InetAddress ip = InetAddress.getLocalHost();
                NetworkInterface network = NetworkInterface.getByInetAddress(ip);
                if (network == null) {
                    id = 1L;
                } else {
                    byte[] mac = network.getHardwareAddress();
                    if (mac != null) {
                        id = ((0x000000FF & (long) mac[mac.length - 1]) | (0x0000FF00 & (((long) mac[mac.length - 2]) << 8))) >> 6;
                        id = id % (maxDatacenterId + 1);
                    }
                }
            } catch (Exception e) {
                System.out.println("get data center id error:" + e.getMessage());
            }
            return id;
        }
     
        /**
         * 获取 maxWorkerId
         */
        protected long getMachineId(long maxWorkerId) {
            long id = 0L;
            try {
                InetAddress ip = InetAddress.getLocalHost();
                NetworkInterface network = NetworkInterface.getByInetAddress(ip);
                if (network == null) {
                    id = 1L;
                } else {
                    byte[] mac = network.getHardwareAddress();
                    if (mac != null) {
                        id = ((0x0000FF & (long) mac[mac.length - 2]) | (0x00FF00 & (((long) mac[mac.length - 1]) << 8))) >> 4;
                        id = id % (maxWorkerId + 1);
                    }
                }
            } catch (Exception e) {
                System.out.println("get machine id error:" + e.getMessage());
            }
            return id;
        }
        
    }

使用：

@Autowired
    private SnowflakeGenerator snowflakeGenerator;
    
    long id = snowflakeGenerator.nextId();