由于redis实现分布式锁不完美：
加锁的代码：
/** * 加锁 * @param locaName 锁的key * @param acquireTimeout 获取超时时间 * @param timeout 锁的超时时间 * @return 锁标识 */ public static String lockWithTimeout(String localName,long timeout) { Jedis conn = null; String retIdentifier = null; try { // 随机生成一个value String identifier = UUID.randomUUID().toString(); // 锁名，即key值 String lockKey = "lock:" + localName; /* * setnx: * 当往redis中存入一个值时,会先判断该值对应的key是否存在,如果存在则返回0,不存在返回1，存值。 */ // 优化：如果判断，设置值，设置过期不具备原子性，那么一旦服务器宕机，就会出现锁不释放，死锁。 /*if(distributedLockUtil.stringRedisTemplate.opsForValue().get(lockKey)==null){ // 优化：不能使用set，因为会覆盖。任何线程进来都能设置锁。将判断，设置值，和设置过期时间写在一起，改为原子性操作。 distributedLockUtil.stringRedisTemplate.opsForValue().set(lockKey,identifier, lockExpire, TimeUnit.SECONDS); // 返回value值，用于释放锁时间确认 retIdentifier = identifier; return retIdentifier; }*/ // 底层也是用的setnx,判断，设置值，设置过期时间要是一个原子性操作，否则宕机会出现锁无法释放。 // setIfAbsent(lockKey, identifier, timeout, TimeUnit.SECONDS)是原子命令。 if(distributedLockUtil.stringRedisTemplate.opsForValue().setIfAbsent(lockKey, identifier, timeout, TimeUnit.SECONDS)){ retIdentifier = identifier; return retIdentifier; } // conn.setnx(lockKey, identifier) == 1,1表示key的值被设置成功，0代表key的值没有被设置。setnx(key,value). // System.out.println(RedisStirngUtils.setIfAbsent(lockKey, identifier)); /*if (RedisStirngUtils.setIfAbsent(lockKey, identifier)) { distributedLockUtil.stringRedisTemplate.expire(lockKey, lockExpire, TimeUnit.SECONDS); // 返回value值，用于释放锁时间确认 retIdentifier = identifier; return retIdentifier; }*/ // 返回-1代表key没有设置超时时间，为key设置一个超时时间 /*if (conn.ttl(lockKey) == -1) { conn.expire(lockKey, lockExpire); }*/ } catch (JedisException e) { e.printStackTrace(); } finally { if (conn != null) { conn.close(); } } return retIdentifier; }
释放锁的代码：
/** * 释放锁 * @param lockName 锁的key * @param identifier 释放锁的标识 * @return */ public static void releaseLock(String lockName,String identifier) { // 优化：如果说哪个小白没有上锁，而是直接调用了releaseLock，那么可能会误删锁，所以需要根据uuid判断是否释放自己上的锁。 // 锁名，即key值 String lockKey = "lock:" + lockName; /* * 优化：假如没有用uuid判断，那么在A线程业务执行时间较长，此时锁过期释放，B线程设置获取锁，此时切换到A线程执行到delete，会把B线程的锁误删。 * 如果并发量较小，可能没什么问题。如果并发量较大就会出现如上问题。 */ /* * 优化：判断和删除不是一个原子性操作，如果A线程判断刚进来，锁刚好过期，然后B线程执行上锁成功，此时切换到A线程执行删除锁，会把B线程的锁误删。 * 这种情况出现的概率很小，但是在极端高并发情况下很可能会出现。 * 解决方案：锁续命。开启一个线程监听(看门狗watch dog)，如果线程没有执行完，那么就把锁续命，延长过期时间。 * 市面上有完善的解决方案redission。底层跟先有代码逻辑一样，只不过多了续命，解决了现有代码逻辑中释放锁中判断和删除的非原子性的问题。 * redission底层使用lua脚本，redis支持lua脚本。 * redission解决了过期时间过期后，锁释放导致误删其他线程加的锁。 * redission放心去用，互联网公司都是这么用的。 */ // 根据uuid只能释放自己的锁。 // 超时时间就是解决宕机导致锁无法释放的问题。 // 优化：如果在超时时间内业务没有完成，需要锁续命。 if(identifier.equals(distributedLockUtil.stringRedisTemplate.opsForValue().get(lockKey))){ // 此时A线程锁过期，B线程加锁，切换A线程执行delete会把线程B的锁删除。 // 但是此时如果有B新增锁，A又删除锁。？？？？ distributedLockUtil.stringRedisTemplate.delete(lockKey); } }
redis实现分布式锁不完美的原因分析：
1.无法解决释放锁的原子性（无法保证原子性就会出现误删key），释放锁需要分为两步：判断是否当前线程，根据key获取value值uuid。判断跟本线程的uuid是否相等，如果相等可以删除key，如果不相等不能删除key。这样解决了A线程误删B线程的key。
但是因为不是原子性，所以会出现判断成立，A线程的key又刚好过期，B线程获取了锁。这时候A线程执行删除key，会误删B线程刚获取的key。无法解决小概率事件的误删key。
2.即使使用lua脚本保证了原子性，彻底解决了A线程误删B线程获取的锁。但是设置过期时间不好控制，假如过期时间设置的不好，会出现A线程还没执行完，B线程就获取了锁。这种情况跟没加锁一样。
这时候就要考虑锁续命问题。这个问题自己开发解决比较麻烦，而且要每一步都考虑线程是否安全。市面上有比较完美的解决方案就是redisson。
redisson的加锁和释放锁都是原子性的，底层实现使用了lua脚本。同时实现了锁自动续命，redisson中的watchdog看门狗来自动实现锁的续命。
这样当线程A没有执行完，就会延长key的过期时间，直到执行到释放锁的代码才会将锁释放。中途如果宕机，redisson会shutdown，锁就不会自动续命，在过期时间后过期（防止死锁）。
redisson完美解决了3个问题：
1.加锁原子性问题（设置过期时间，中途宕机产生死锁）
2.释放锁原子性问题（A线程误删B线程的锁）。
3.锁过期时间控制问题（A线程没执行完，锁就过期了，B线程就会获取锁。这样就失去了锁的作用，相当于没加锁，A和B线程同时运行）。
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redisson实现分布式锁：（spring整合redisson）（注意：redisson需要springboot2.0及以上或者spring5.0及以上）
1.引入jar包：
spring的相关jar包。
redisson相关jar包：redisson-3.16.0.jar，netty-all-4.1.48.Final.jar，jboss-marshalling-2.0.3.Final.jar，jackson-dataformat-yaml-2.9.9.jar。
2.通过java代码配置RedissonClient的bean。
package com.user.base.utils.redis.redisson; import java.io.IOException; import org.redisson.Redisson; import org.redisson.api.RedissonClient; import org.redisson.config.Config; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; /** * 获取redisson * @author Administrator * */ @Configuration public class RedissonConfig { /* * 在SecondKillServiceImp.java中使用 */ @Bean/*(destroyMethod = "shutdown")*/ RedissonClient redisson(){ // throws IOException Config config = new Config(); //config.useClusterServers().addNodeAddress("127.0.0.1:6379"); config.useSingleServer().setAddress("redis://127.0.0.1:64791"); //config.useClusterServers().addNodeAddress("redis://127.0.0.1:6379","redis://127.0.0.1:6380"); config.setCodec(new org.redisson.client.codec.StringCodec()); RedissonClient redissonClient = null; try{ redissonClient = Redisson.create(config); }catch(Exception e){ e.printStackTrace(); } return redissonClient; } }
config.useSingleServer().setAddress("redis://127.0.0.1:64791");表示用的单个机器。
config.useClusterServers().addNodeAddress("redis://127.0.0.1:6379","redis://127.0.0.1:6380");是集群方式。
如果搭建好了集群可以使用集群方式。我这里有部署好的集群也有单机。这里暂时使用单机测试。（redis集群部署参考：https://www.cnblogs.com/super-chao/p/9329018.html）
3.使用RedissonClient获取锁RLock。通过RLock进行加锁，释放锁。
接口：SecondKillService.java
package com.user.service.redis; public interface SecondKillService { public void seckill(); }
实现类：SecondKillServiceImp.java
package com.user.service.redis; import java.util.ArrayList; import java.util.List; import java.util.concurrent.TimeUnit; import org.apache.commons.lang3.StringUtils; import org.redisson.api.RLock; import org.redisson.api.RedissonClient; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import com.user.base.utils.redis.DistributedLockUtils; import com.user.base.utils.redis.DistributedLockUtils2; import com.user.base.utils.redis.redisson.RedissonConfig; @Service public class SecondKillServiceImp implements SecondKillService{ @Autowired private RedissonClient redissonClient; private static int count = 2000; public static List<Integer> list = new ArrayList<>(); // @Override // public void seckill() { // System.out.println("当前线程："+Thread.currentThread().getName()+"获得了锁"); // // 可以防止重复提交的数据。 // String uuid = DistributedLockUtils2.lockWithTimeout("test", 10); // // 上锁，如果锁一直保持，其他线程无法操作，只有过期或者主动释放锁。 // try { // if(StringUtils.isNotEmpty(uuid)){ // System.out.println(Thread.currentThread().getName()+"秒杀操作"); // }else{ // System.out.println("系统繁忙，请稍后再试。"); // } // } catch (Exception e) { // e.printStackTrace(); // } finally { // // 如果业务代码出现异常了，不在finally中执行释放锁的操作，也会导致锁无法释放。 // DistributedLockUtils2.releaseLock("test",uuid); // } // } @Override public void seckill() { RLock redissonLock = redissonClient.getLock("test"); // 相当于distributedLockUtil.stringRedisTemplate.opsForValue().setIfAbsent(lockKey, identifier, timeout, TimeUnit.SECONDS) redissonLock.lock(); try { count = count - 1; list.add(count); System.out.println(Thread.currentThread().getName() + "秒杀操作," + "剩余数量：" + count); } catch (Exception e) { e.printStackTrace(); } finally { // 相当于distributedLockUtil.stringRedisTemplate.delete(lockKey); /* * 由于开启了watchdog看门狗线程监听，所以线程执行完之前不会出现：A线程锁过期时间过期，此时B线程设置锁，然后又切换到A线程删锁，误删B线程的锁。 * 因为A线程执行完之前，A线程的锁会一直续命，不会过期。所以A线程在delete锁之前，会一直持有锁。 * 如果服务器非宕机情况，那么锁会一直续命，A线程一直持有锁。最终都会执行到finally释放锁。 * 如果中间出现宕机，那么锁不会续命，到了过期时间就会过期。锁自动释放。 * 因此不会出现锁无法释放，死锁的情况。 * * 自己写续命比较麻烦，而且容易出错。redisson是个很好的框架和解决方案。 */ redissonLock.unlock(); } } }
这里有个小细节需要注意：redissonLock.lock();一定要写在try外面，如果写在里面那么当redissonLock.lock()出现异常，依然会走finally中释放锁的代码，又会出现新的异常。
写在try外面，redissonLock.lock()一旦出现异常，程序就会终止，finally中的释放锁的代码就不会执行。不会产生新的异常。
4.测试
线程类：SecondKillThread.java
package com.user.service.redis; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component; @Component public class SecondKillThread implements Runnable{ @Autowired private SecondKillService secondKillService; @Override public void run() { secondKillService.seckill(); } }
测试类：RedisDistributedLockTest.java
package com.user.test.spring_redis; import java.util.HashSet; import java.util.Iterator; import java.util.Set; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.test.context.ContextConfiguration; import org.springframework.test.context.junit4.AbstractJUnit4SpringContextTests; import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import com.user.service.redis.SecondKillService; import com.user.service.redis.SecondKillServiceImp; import com.user.service.redis.SecondKillThread; @RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration({"classpath:applicationContext.xml"}) public class RedisDistributedLockTest extends AbstractJUnit4SpringContextTests{ @Autowired private SecondKillService secondKillService; @Autowired private SecondKillThread secondKillThread; /** * 模拟秒杀 */ @Test public void secKill(){ System.out.println("秒杀活动开始---"); try { for(int i=0;i<2000;i++){ new Thread(secondKillThread).start(); } //secondKillService.seckill(); } catch (Exception e) { e.printStackTrace(); } try { Thread.sleep(10000); } catch (InterruptedException e1) { e1.printStackTrace(); } System.out.println(SecondKillServiceImp.list); Set set = new HashSet(); for(int i : SecondKillServiceImp.list){ int count = 0; for(int j : SecondKillServiceImp.list){ if(i == j){ count = count + 1; } } if(count > 1){ set.add(i); } } if(set != null && set.size() > 0){ // Iterator it = set.iterator(); // while(it.hasNext()){ // System.out.println(it.next()); // } System.out.println(set); }else{ System.out.println("没有重复的记录！"); } } }
5.结果
1.假如将redisson获取锁，释放锁注释掉，即没有使用锁。
junit测试运行方法secKill()
2000个商品，开启2000个线程来购买即商品数量减1，理论上来说应该最后结果count为0.
消费列表：
[1999, 1998, 1997, 1996, 1995, 1994, 1993, 1992, 1991, 1990, 1989, 1988, 1987, 1986, 1985, 1984, 1983, 1982, 1981, 1980, 1979, 1978, 1977, 1976, 1975, 1974, 1973, 1972, 1971, 1970, 1969, 1968, 1967, 1966, 1965, 1964, 1963, 1962, 1961, 1960, 1959, 1958, 1957, 1956, 1955, 1954, 1953, 1952, 1951, 1950, 1949, 1948, 1947, 1946, 1945, 1944, 1943, 1942, 1941, 1940, 1939, 1938, 1937, 1936, 1935, 1934, 1933, 1932, 1931, 1930, 1929, 1928, 1927, 1926, 1925, 1924, 1923, 1922, 1921, 1920, 1919, 1918, 1917, 1916, 1915, 1914, 1913, 1912, 1911, 1910, 1909, 1908, 1907, 1906, 1905, 1904, 1903, 1902, 1901, 1900, 1899, 1898, 1897, 1896, 1895, 1894, 1893, 1892, 1891, 1890, 1889, 1888, 1887, 1886, 1885, 1884, 1883, 1882, 1881, 1880, 1879, 1878, 1877, 1876, 1875, 1874, 1873, 1872, 1871, 1870, 1869, 1868, 1867, 1866, 1865, 1864, 1863, 1862, 1861, 1860, 1859, 1858, 1857, 1856, 1855, 1854, 1853, 1852, 1851, 1850, 1849, 1848, 1847, 1846, 1845, 1844, 1843, 1842, 1841, 1840, 1839, 1838, 1837, 1836, 1835, 1834, 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1004, 1003, 1002, 1001, 1000, 999, 998, 997, 996, 995, 994, 993, 992, 991, 990, 989, 988, 987, 986, 985, 984, 983, 982, 981, 980, 979, 978, 977, 976, 975, 974, 973, 972, 971, 970, 969, 968, 967, 966, 965, 964, 963, 962, 961, 960, 959, 958, 957, 956, 955, 954, 953, 952, 951, 950, 949, 948, 947, 946, 945, 944, 943, 942, 941, 940, 939, 938, 937, 936, 935, 934, 933, 932, 931, 930, 929, 928, 927, 926, 925, 924, 923, 922, 921, 920, 919, 918, 917, 916, 915, 914, 913, 912, 911, 910, 909, 908, 907, 906, 905, 904, 903, 902, 901, 900, 899, 898, 897, 896, 895, 894, 893, 892, 891, 890, 889, 888, 887, 886, 885, 884, 883, 882, 881, 880, 879, 878, 877, 876, 875, 874, 873, 872, 871, 870, 869, 868, 867, 866, 865, 864, 863, 862, 861, 860, 859, 858, 857, 856, 855, 854, 853, 852, 851, 850, 849, 848, 847, 846, 845, 844, 843, 842, 841, 840, 839, 838, 837, 836, 835, 834, 833, 832, 831, 830, 829, 828, 827, 826, 825, 824, 823, 822, 821, 820, 819, 818, 817, 816, 815, 814, 813, 812, 811, 810, 809, 808, 807, 806, 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重复消费列表：
[1140]
可以看到1140被重复消费了。这就出现了线程安全问题。count没有及时刷新到主内存，导致另一个线程读到的不是最新的数据（jmm内存模型：主内存，本地内存（线程内存））。
多次运行结果，大部分出现的都是重复消费了，count最后结果都不为0.
2.使用redisson分布式锁。（多个jvm上，如果其中一个jvm中线程获取锁，那么redis中的key被设置，其他jvm中线程就无法获取锁而等待）
消费列表：
[1999, 1998, 1997, 1996, 1995, 1994, 1993, 1992, 1991, 1990, 1989, 1988, 1987, 1986, 1985, 1984, 1983, 1982, 1981, 1980, 1979, 1978, 1977, 1976, 1975, 1974, 1973, 1972, 1971, 1970, 1969, 1968, 1967, 1966, 1965, 1964, 1963, 1962, 1961, 1960, 1959, 1958, 1957, 1956, 1955, 1954, 1953, 1952, 1951, 1950, 1949, 1948, 1947, 1946, 1945, 1944, 1943, 1942, 1941, 1940, 1939, 1938, 1937, 1936, 1935, 1934, 1933, 1932, 1931, 1930, 1929, 1928, 1927, 1926, 1925, 1924, 1923, 1922, 1921, 1920, 1919, 1918, 1917, 1916, 1915, 1914, 1913, 1912, 1911, 1910, 1909, 1908, 1907, 1906, 1905, 1904, 1903, 1902, 1901, 1900, 1899, 1898, 1897, 1896, 1895, 1894, 1893, 1892, 1891, 1890, 1889, 1888, 1887, 1886, 1885, 1884, 1883, 1882, 1881, 1880, 1879, 1878, 1877, 1876, 1875, 1874, 1873, 1872, 1871, 1870, 1869, 1868, 1867, 1866, 1865, 1864, 1863, 1862, 1861, 1860, 1859, 1858, 1857, 1856, 1855, 1854, 1853, 1852, 1851, 1850, 1849, 1848, 1847, 1846, 1845, 1844, 1843, 1842, 1841, 1840, 1839, 1838, 1837, 1836, 1835, 1834, 1833, 1832, 1831, 1830, 1829, 1828, 1827, 1826, 1825, 1824, 1823, 1822, 1821, 1820, 1819, 1818, 1817, 1816, 1815, 1814, 1813, 1812, 1811, 1810, 1809, 1808, 1807, 1806, 1805, 1804, 1803, 1802, 1801, 1800, 1799, 1798, 1797, 1796, 1795, 1794, 1793, 1792, 1791, 1790, 1789, 1788, 1787, 1786, 1785, 1784, 1783, 1782, 1781, 1780, 1779, 1778, 1777, 1776, 1775, 1774, 1773, 1772, 1771, 1770, 1769, 1768, 1767, 1766, 1765, 1764, 1763, 1762, 1761, 1760, 1759, 1758, 1757, 1756, 1755, 1754, 1753, 1752, 1751, 1750, 1749, 1748, 1747, 1746, 1745, 1744, 1743, 1742, 1741, 1740, 1739, 1738, 1737, 1736, 1735, 1734, 1733, 1732, 1731, 1730, 1729, 1728, 1727, 1726, 1725, 1724, 1723, 1722, 1721, 1720, 1719, 1718, 1717, 1716, 1715, 1714, 1713, 1712, 1711, 1710, 1709, 1708, 1707, 1706, 1705, 1704, 1703, 1702, 1701, 1700, 1699, 1698, 1697, 1696, 1695, 1694, 1693, 1692, 1691, 1690, 1689, 1688, 1687, 1686, 1685, 1684, 1683, 1682, 1681, 1680, 1679, 1678, 1677, 1676, 1675, 1674, 1673, 1672, 1671, 1670, 1669, 1668, 1667, 1666, 1665, 1664, 1663, 1662, 1661, 1660, 1659, 1658, 1657, 1656, 1655, 1654, 1653, 1652, 1651, 1650, 1649, 1648, 1647, 1646, 1645, 1644, 1643, 1642, 1641, 1640, 1639, 1638, 1637, 1636, 1635, 1634, 1633, 1632, 1631, 1630, 1629, 1628, 1627, 1626, 1625, 1624, 1623, 1622, 1621, 1620, 1619, 1618, 1617, 1616, 1615, 1614, 1613, 1612, 1611, 1610, 1609, 1608, 1607, 1606, 1605, 1604, 1603, 1602, 1601, 1600, 1599, 1598, 1597, 1596, 1595, 1594, 1593, 1592, 1591, 1590, 1589, 1588, 1587, 1586, 1585, 1584, 1583, 1582, 1581, 1580, 1579, 1578, 1577, 1576, 1575, 1574, 1573, 1572, 1571, 1570, 1569, 1568, 1567, 1566, 1565, 1564, 1563, 1562, 1561, 1560, 1559, 1558, 1557, 1556, 1555, 1554, 1553, 1552, 1551, 1550, 1549, 1548, 1547, 1546, 1545, 1544, 1543, 1542, 1541, 1540, 1539, 1538, 1537, 1536, 1535, 1534, 1533, 1532, 1531, 1530, 1529, 1528, 1527, 1526, 1525, 1524, 1523, 1522, 1521, 1520, 1519, 1518, 1517, 1516, 1515, 1514, 1513, 1512, 1511, 1510, 1509, 1508, 1507, 1506, 1505, 1504, 1503, 1502, 1501, 1500, 1499, 1498, 1497, 1496, 1495, 1494, 1493, 1492, 1491, 1490, 1489, 1488, 1487, 1486, 1485, 1484, 1483, 1482, 1481, 1480, 1479, 1478, 1477, 1476, 1475, 1474, 1473, 1472, 1471, 1470, 1469, 1468, 1467, 1466, 1465, 1464, 1463, 1462, 1461, 1460, 1459, 1458, 1457, 1456, 1455, 1454, 1453, 1452, 1451, 1450, 1449, 1448, 1447, 1446, 1445, 1444, 1443, 1442, 1441, 1440, 1439, 1438, 1437, 1436, 1435, 1434, 1433, 1432, 1431, 1430, 1429, 1428, 1427, 1426, 1425, 1424, 1423, 1422, 1421, 1420, 1419, 1418, 1417, 1416, 1415, 1414, 1413, 1412, 1411, 1410, 1409, 1408, 1407, 1406, 1405, 1404, 1403, 1402, 1401, 1400, 1399, 1398, 1397, 1396, 1395, 1394, 1393, 1392, 1391, 1390, 1389, 1388, 1387, 1386, 1385, 1384, 1383, 1382, 1381, 1380, 1379, 1378, 1377, 1376, 1375, 1374, 1373, 1372, 1371, 1370, 1369, 1368, 1367, 1366, 1365, 1364, 1363, 1362, 1361, 1360, 1359, 1358, 1357, 1356, 1355, 1354, 1353, 1352, 1351, 1350, 1349, 1348, 1347, 1346, 1345, 1344, 1343, 1342, 1341, 1340, 1339, 1338, 1337, 1336, 1335, 1334, 1333, 1332, 1331, 1330, 1329, 1328, 1327, 1326, 1325, 1324, 1323, 1322, 1321, 1320, 1319, 1318, 1317, 1316, 1315, 1314, 1313, 1312, 1311, 1310, 1309, 1308, 1307, 1306, 1305, 1304, 1303, 1302, 1301, 1300, 1299, 1298, 1297, 1296, 1295, 1294, 1293, 1292, 1291, 1290, 1289, 1288, 1287, 1286, 1285, 1284, 1283, 1282, 1281, 1280, 1279, 1278, 1277, 1276, 1275, 1274, 1273, 1272, 1271, 1270, 1269, 1268, 1267, 1266, 1265, 1264, 1263, 1262, 1261, 1260, 1259, 1258, 1257, 1256, 1255, 1254, 1253, 1252, 1251, 1250, 1249, 1248, 1247, 1246, 1245, 1244, 1243, 1242, 1241, 1240, 1239, 1238, 1237, 1236, 1235, 1234, 1233, 1232, 1231, 1230, 1229, 1228, 1227, 1226, 1225, 1224, 1223, 1222, 1221, 1220, 1219, 1218, 1217, 1216, 1215, 1214, 1213, 1212, 1211, 1210, 1209, 1208, 1207, 1206, 1205, 1204, 1203, 1202, 1201, 1200, 1199, 1198, 1197, 1196, 1195, 1194, 1193, 1192, 1191, 1190, 1189, 1188, 1187, 1186, 1185, 1184, 1183, 1182, 1181, 1180, 1179, 1178, 1177, 1176, 1175, 1174, 1173, 1172, 1171, 1170, 1169, 1168, 1167, 1166, 1165, 1164, 1163, 1162, 1161, 1160, 1159, 1158, 1157, 1156, 1155, 1154, 1153, 1152, 1151, 1150, 1149, 1148, 1147, 1146, 1145, 1144, 1143, 1142, 1141, 1140, 1139, 1138, 1137, 1136, 1135, 1134, 1133, 1132, 1131, 1130, 1129, 1128, 1127, 1126, 1125, 1124, 1123, 1122, 1121, 1120, 1119, 1118, 1117, 1116, 1115, 1114, 1113, 1112, 1111, 1110, 1109, 1108, 1107, 1106, 1105, 1104, 1103, 1102, 1101, 1100, 1099, 1098, 1097, 1096, 1095, 1094, 1093, 1092, 1091, 1090, 1089, 1088, 1087, 1086, 1085, 1084, 1083, 1082, 1081, 1080, 1079, 1078, 1077, 1076, 1075, 1074, 1073, 1072, 1071, 1070, 1069, 1068, 1067, 1066, 1065, 1064, 1063, 1062, 1061, 1060, 1059, 1058, 1057, 1056, 1055, 1054, 1053, 1052, 1051, 1050, 1049, 1048, 1047, 1046, 1045, 1044, 1043, 1042, 1041, 1040, 1039, 1038, 1037, 1036, 1035, 1034, 1033, 1032, 1031, 1030, 1029, 1028, 1027, 1026, 1025, 1024, 1023, 1022, 1021, 1020, 1019, 1018, 1017, 1016, 1015, 1014, 1013, 1012, 1011, 1010, 1009, 1008, 1007, 1006, 1005, 1004, 1003, 1002, 1001, 1000, 999, 998, 997, 996, 995, 994, 993, 992, 991, 990, 989, 988, 987, 986, 985, 984, 983, 982, 981, 980, 979, 978, 977, 976, 975, 974, 973, 972, 971, 970, 969, 968, 967, 966, 965, 964, 963, 962, 961, 960, 959, 958, 957, 956, 955, 954, 953, 952, 951, 950, 949, 948, 947, 946, 945, 944, 943, 942, 941, 940, 939, 938, 937, 936, 935, 934, 933, 932, 931, 930, 929, 928, 927, 926, 925, 924, 923, 922, 921, 920, 919, 918, 917, 916, 915, 914, 913, 912, 911, 910, 909, 908, 907, 906, 905, 904, 903, 902, 901, 900, 899, 898, 897, 896, 895, 894, 893, 892, 891, 890, 889, 888, 887, 886, 885, 884, 883, 882, 881, 880, 879, 878, 877, 876, 875, 874, 873, 872, 871, 870, 869, 868, 867, 866, 865, 864, 863, 862, 861, 860, 859, 858, 857, 856, 855, 854, 853, 852, 851, 850, 849, 848, 847, 846, 845, 844, 843, 842, 841, 840, 839, 838, 837, 836, 835, 834, 833, 832, 831, 830, 829, 828, 827, 826, 825, 824, 823, 822, 821, 820, 819, 818, 817, 816, 815, 814, 813, 812, 811, 810, 809, 808, 807, 806, 805, 804, 803, 802, 801, 800, 799, 798, 797, 796, 795, 794, 793, 792, 791, 790, 789, 788, 787, 786, 785, 784, 783, 782, 781, 780, 779, 778, 777, 776, 775, 774, 773, 772, 771, 770, 769, 768, 767, 766, 765, 764, 763, 762, 761, 760, 759, 758, 757, 756, 755, 754, 753, 752, 751, 750, 749, 748, 747, 746, 745, 744, 743, 742, 741, 740, 739, 738, 737, 736, 735, 734, 733, 732, 731, 730, 729, 728, 727, 726, 725, 724, 723, 722, 721, 720, 719, 718, 717, 716, 715, 714, 713, 712, 711, 710, 709, 708, 707, 706, 705, 704, 703, 702, 701, 700, 699, 698, 697, 696, 695, 694, 693, 692, 691, 690, 689, 688, 687, 686, 685, 684, 683, 682, 681, 680, 679, 678, 677, 676, 675, 674, 673, 672, 671, 670, 669, 668, 667, 666, 665, 664, 663, 662, 661, 660, 659, 658, 657, 656, 655, 654, 653, 652, 651, 650, 649, 648, 647, 646, 645, 644, 643, 642, 641, 640, 639, 638, 637, 636, 635, 634, 633, 632, 631, 630, 629, 628, 627, 626, 625, 624, 623, 622, 621, 620, 619, 618, 617, 616, 615, 614, 613, 612, 611, 610, 609, 608, 607, 606, 605, 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重复消费列表：
没有重复的记录！
不管运行多少次，count最终都为0，不会出现重复消费。