D > B enters the synchronized block, and since instance is not null at this time, it immediately leaves the synchronized block and returns the result to the program calling the method. E > At this point, thread B intends to use the Singleton instance, only to find that it has not been initialized, so an error occurs. Therefore, there is still the possibility of errors in the program. In fact, the running process of the program is very complicated. From this, we can see that it is more difficult and challenging to write programs especially in multi-threaded environment. We further optimized the program:
CBS宣布续订《警察世家》第11季。
那个娘也就罢了——当娘的见闺女被人踢了，肯定是这副样子，可那个小女孩，睁着一双干净的眼眸，就那么看着他，静静的。
没有人明白这是为什么。当神秘的停电解除后，被这次事件影响的人们逐渐回归正常生活，除了该区域内的每一位育龄女性突然莫名其妙怀孕了。
1885年，法军进攻越南凉山，驻守清军不战而退，清朝政府的统治地位遭到威胁，慈禧召集众臣商讨派谁挂帅，最终启用了年近七旬的退隐老将冯子材（刘佩琦 饰），但当时广西军民已被法军的残忍手段吓破胆，有严重畏战情绪。为了激励军民，冯子材出奇兵成功伏击攻克龙临镇的北非雇佣军，生擒黑人上尉克拉克，并当众与其决斗，刀斩悍敌，振奋军心。
剧情讲述一位芭蕾舞姬和一位富二代甜蜜相恋，但富二代因为意外过世，芭蕾舞姬想随之殉情，但是她却神奇地回到了过去，那个她和富二代尚未相识的时候，她和富二代能否再续前缘呢？
许负轻轻一笑道：千万别这样说，这一切都是天意，姐姐回归越王身边，母仪天下，乃是上天注定的事情。
把肚子填饱了，再去别处逛。
9. December-February in winter, By this time the lobsters had all entered the cave to escape the cold. By this time lobster was already in short supply, It was the highest price of the year, Our situation on the ground is that, By this time, Some idle people took shovels and dug holes everywhere to catch lobsters. At this time, there is usually no water in the pond. Lobster holes are all on the shore, An experienced person can see the lobster hole at a glance. At this time, some of them can be caught and sold. The price is generally twice that of summer. Of course, lobsters with eggs should be put back. It is said above that they basically hatch in October. Why are there still lobsters with eggs at this time? It is because lobsters are of different sizes and do not mature sexually at the same time. At this time, lobsters usually do not hatch until March of the following year because of the low temperature. Our local price at this time is: Lobster with mud collected 18-20% last year, basically with half of the mud, which is about 30 yuan. Taking mud in winter makes people feel that it was dug out of the hole. Even if it is not, it will be pasted with mud, which is basically a hidden rule. Just like selling crabs with ropes, selling 70 people without ropes is too expensive. Taking a few taels of ropes and lowering the price will make it easier for people to accept it.
郑氏便对二人道：等明年，就让你们一起去学里读书，随你们混去。
Public void accept (Visitor visitor);
该剧主要讲述抢不到从地球回到喵星球，偶遇一只折耳猫，他发现这只猫就是曾经和他在地球上相爱的小Q。他用尽办法让小Q想起自己，却未曾想命运再次作弄，一个“折耳猫寓言”打破了他们的幸福，为帮小Q打碎寓言，抢不到不听喵星长老劝阻，毅然穿越回地球。等待他们的是幸福还是永别，没人知道，新的一场生死之恋在喵星与地球的穿越中慢慢展开。
Introduction: Smiling back somersault, use it when winning joy.
努尔特之王计划窃取夜间动物园的颜色，使动物处于极大的危险之中！而夜间动物园管理员威尔和他的朋友能拯救夜晚动物园吗？
进宫后，所有人把车马停在长安门广场，然后步行入宫。
依如昔年对抗六国合纵，可惜大秦已经不是当年的大秦了。
So let's explain the rules of iptables in a common way. There was an analogy before, Each "chain" is a "checkpoint", Every message passing through this "level" must match the rules on this level. If there is a match, The message is processed correspondingly, For example, you and I are like two "messages" at the moment. Both of you and I are going to enter the customs at this moment. But the duke has a life, Only the imposing person can enter the customs, Those who do not meet this requirement are not allowed to enter the customs. So the soldiers guarding the customs followed the "rules" formulated by the duke. I began to look at you and me. In the end, you entered the customs smoothly, and I was rejected. Because you met the standard of "dignity", you were "released", while I did not meet the standard, so I was not released. In fact, "dignity" is a kind of "matching condition", "release" is a kind of "action", and "matching condition" and "action" form the rules.
故事讲述戏精怂包少女遇上冷酷凶恶大叔的故事，两个性格迥异的家伙擦出爆笑治愈的火花！本剧根据腾讯动漫《酷大叔的恋爱物语》改编。
