使用数据库和Redis开发各系统独立的自增ID生成器

DROP TABLE IF EXISTS sys_id_record; 
CREATE TABLE sys_id_record( 
id INT UNSIGNED AUTO_INCREMENT, 
sys_id VARCHAR(40) NOT NULL COMMENT '子系统ID', 
sys_name VARCHAR(100) NOT NULL COMMENT '子系统名称', 
id_from INT NOT NULL DEFAULT 1 COMMENT '子系统ID起始值', 
lenth SMALLINT NOT NULL DEFAULT 10 COMMENT '子系统ID长度', 
enabled VARCHAR(1) NOT NULL DEFAULT 'Y', 
created_by VARCHAR(40) NOT NULL COMMENT '创建人', 
created_date DATETIME COMMENT '创建时间', 
updated_by VARCHAR(40) NOT NULL COMMENT '更新人', 
updated_date DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间', 
PRIMARY KEY ( id ) 
)ENGINE=INNODB DEFAULT CHARSET=utf8; 

package com.davidwang456.test; 
 
 
public interface IDGenerateService { 
  String getIDGenerateBySys(String sysId); 
} 

package com.davidwang456.test; 
 
import java.util.ArrayList; 
import java.util.List; 
 
import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.data.redis.core.RedisTemplate; 
import org.springframework.stereotype.Service; 
 
@Service 
public class IDGenerateServiceImpl implements IDGenerateService { 
   @Autowired 
   private SysIdRecordDao sysIdRecordDao; 
    
   @Autowired 
   private RedisTemplate redisTemplate; 
 
    @Override 
    public String getIDGenerateBySys(String sysId) { 
        init(sysId); 
        Object idSys=redisTemplate.opsForList().rightPop(sysId); 
        if(idSys==null) { 
            List<SysIdRecord> records=sysIdRecordDao.getEnabledSysIdRecord(sysId); 
            if(records!=null&&records.isEmpty()) { 
                SysIdRecord record=records.get(0); 
                 
                List<Integer> buf_ids=new ArrayList<>(); 
                for(int i=1;i<record.getLenth+1;i++) { 
                    buf_ids.add(record.getIdFrom+i); 
                } 
                redisTemplate.opsForList().leftPushAll(sysId, buf_ids); 
                record.setIdFrom(record.getIdFrom()+record.getLenth()); 
                sysIdRecordDao.save(record); 
                idSys=redisTemplate.opsForList().rightPop(sysId); 
            } 
        } 
        return sysId+":"+idSys; 
    } 
     
    private void init(String sysId) { 
        if(!redisTemplate.hasKey(sysId)) { 
            List<SysIdRecord> records=sysIdRecordDao.getEnabledSysIdRecord(sysId); 
            if(records==null||records.isEmpty()) { 
                SysIdRecord record=new SysIdRecord(); 
                //TODO 
                sysIdRecordDao.save(record); 
            } 
        } 
 
    } 
 
}