import org.apache.commons.lang3.RandomUtils; import java.net.InetAddress; import java.time.LocalDateTime; import java.time.ZoneId; import java.time.format.DateTimeFormatter; import java.util.ArrayList; import java.util.Collections; import java.util.List; import java.util.concurrent.atomic.AtomicInteger; import java.util.stream.Collectors; import java.util.stream.IntStream; public class OrderGen2Test { /** 订单号生成 **/ private static ZoneId ZONE_ID = ZoneId.of("Asia/Shanghai"); private static final AtomicInteger SEQ = new AtomicInteger(1000); private static final DateTimeFormatter DF_FMT_PREFIX = DateTimeFormatter.ofPattern("yyMMddHHmmssSS"); public static String generateOrderNo(){ LocalDateTime dataTime = LocalDateTime.now(ZONE_ID); if(SEQ.intValue()>9990){ SEQ.getAndSet(1000); } return dataTime.format(DF_FMT_PREFIX)+ getLocalIpSuffix()+SEQ.getAndIncrement(); } private volatile static String IP_SUFFIX = null; private static String getLocalIpSuffix (){ if(null != IP_SUFFIX){ return IP_SUFFIX; } try { synchronized (OrderGen2Test.class){ if(null != IP_SUFFIX){ return IP_SUFFIX; } InetAddress addr = InetAddress.getLocalHost(); // 172.17.0.4 172.17.0.199 , String hostAddress = addr.getHostAddress(); if (null != hostAddress && hostAddress.length() > 4) { String ipSuffix = hostAddress.trim().split("\\.")[3]; if (ipSuffix.length() == 2) { IP_SUFFIX = ipSuffix; return IP_SUFFIX; } ipSuffix = "0" + ipSuffix; IP_SUFFIX = ipSuffix.substring(ipSuffix.length() - 2); return IP_SUFFIX; } IP_SUFFIX = RandomUtils.nextInt(10, 20) + ""; return IP_SUFFIX; } }catch (Exception e){ System.out.println("获取IP失败:"+e.getMessage()); IP_SUFFIX = RandomUtils.nextInt(10,20)+""; return IP_SUFFIX; } } public static void main(String[] args) { List<String> orderNos = Collections.synchronizedList(new ArrayList<String>()); IntStream.range(0,8000).parallel().forEach(i->{ orderNos.add(generateOrderNo()); }); List<String> filterOrderNos = orderNos.stream().distinct().collect(Collectors.toList()); System.out.println("订单样例:"+ orderNos.get(22)); System.out.println("生成订单数:"+orderNos.size()); System.out.println("过滤重复后订单数:"+filterOrderNos.size()); System.out.println("重复订单数:"+(orderNos.size()-filterOrderNos.size())); } } /** 订单样例:20082115575546011022 生成订单数:8000 过滤重复后订单数:8000 重复订单数:0 **/ |