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:
历史学家露西·沃斯利带我们走进三处藏有宝藏的皇家宫殿，揭开每一座建筑是如何塑造一个君主政体和一个国家的。通过独家访问白金汉宫最秘密的地方，她揭露了戏剧性的事件，改变了英国历史的进程，从伦敦塔的威吓和汉普顿宫的绝对君主制的兴衰，到现代皇室在肯辛顿宫的面孔。
清末，朝政腐败，民不聊生。药店少东黄麒英（黄日华）富正义感，拜南拳王陆阿采为师，练得一身好功夫。北腿王传人田慧男（梁琤），南下为父报仇，巧遇英，两人建立深厚情谊。富商独女宋绮文（刘锦玲）敬佩英的侠义行为，心生倾慕，但英却钟情男，而天生神力的铁桥三（郭政鸿）却又暗恋文……增）为两广总督，表面不懂武功，实得鹰爪功真传，武功高强，暗地里借白莲教之名，荼毒百姓。男杀父仇人苗卓峰为找寻鹰爪王南下，联同采创新招式欲破鹰爪功，惜二人同遭莽毒手，临终前将毕生武术分别传给英与男。 后英以「虎鹤双型拳」大破白莲教，识破莽之阴谋，更与男联创「无影腿」破鹰爪杀莽，完成采、苗的遗愿。但英、男与文纠缠不清的三角关系，他们又如何自处呢？
《行尸走肉第四季》故事发展到第四季，监狱避难营中的人数不断地增长着，生活也渐渐步入了正轨，正当大家以为平静的日子终于来临之时，总督（大卫·莫瑞瑟 David Morrissey 饰）的逆袭让瑞克（安德鲁·林肯 Andrew Lincoln 饰）一行人再度陷入到了水深火热之中。
玄武王可是奉旨来追我们，一定要取我们性命的。
爱丽丝向陈启挥手道。
不管其他人怎么想怎么看，反正李峰绝不接受那样的张无忌。
落魄的青年经纪人武大，无意获得了一幅改变其命运的古画。在家传聚宝盆的作用下，四名古代美女：西施、花木兰、妲己和杨玉环，穿越时空现身2018。她们的出现让武大对生活重新燃起希望。于是，开始游说四女成立“舞魅娘”舞蹈团，并参加了一场足以扬名立万的舞蹈大赛——“天下第一舞道会”！四女虽凭借从各自时空带来的技艺开始崭露头角，然而毕竟古今有别，舞蹈大会更是强者如林，劲敌“唯舞独尊”的出现也让几位曾高高在上的绝代佳人初次尝到了失败的滋味。而几位画中人，也开始明白了时代的变化，一方面磨砺着舞技，另一方面也开始经历各自不同的情感生涯。
The singleton mode is characterized by two classes (one business class construction method is private, and the other factory class is responsible for saving singletons of business classes. Pay attention to the use of multithreading)
When we have added a series of validation rules to the validator object, we will call the validator.start () method to start the validation. If validator.start () returns an errorMsg string as the return value, indicating that the validation failed, the registerForm.onsubmit method is required to return false to prevent form submission. Let's take a look at the initialization code as follows:
"It 's a flying bee, Wings are particularly numerous, He was covered in yellow and black, It is the way yellow and black are arranged in such a way. One by one is as big as a slap with an open hand. As soon as it flies, it is a large area. There is a poisonous needle behind the belly, It stings people, One can kill you, My comrades around me, Because there are no fewer than five sacrifices, I remember when the battle was coming to an end, I helped a comrade-in-arms who was stung to squeeze poison out, To squeeze, The wound, which was almost the size of a grain of rice, gushed out a pale yellow 'water', Sprayed directly on my neck, At that time, I felt that my neck was burning, then I felt pain first, then numbness. At the most numbness, my whole head lost consciousness. My neck drooped down and my comrades washed the spilled place several times with river water. It took me a long time to recover. I thought that it was the same when I sprayed it on my body. If I stung it directly into my body, I would basically not live. " Zhang Xiaobo pointed to his neck as he said.
2.4. 2 Identification Point Requirements
溴Br是阻燃剂，钡Ba则主要用于制造焰火。一个是阻燃一个是焰火，Walter的内心也仿佛在这里挣扎。Walter是绝对的好人。他裸体穿围裙戴防毒面罩，目的是不想弄脏了漂亮的衬衫；给大毒贩做三明治小心的切掉面包的边角；自己偷了实验室的仪器却害学校的清洁大叔被怀疑，他心里极度不安。Walter也绝对是个狠角色。用氢氟酸溶掉毒贩子的尸体，他让拍档去买塑料盆装着尸体。拿着雷酸汞装作是冰毒去会毒贩子，一颗小晶体炸得天摇地动，毒贩子弱弱的问，你手上那是什么？他说，简单的化学原理而已。Walter的生命放佛是璀璨的焰火，Breaking是他固有道德的破点，Bad就是他出于对家庭的爱所作的一切为人不齿的毒品勾当。说到爱，也许一切都能被纵容。
本片根据福本伸行的漫画原作改编。描述的是在藏龙卧虎的麻将世界，江山代有英豪出，今日是只手遮天的帝王，明天就可能败在麻坛新秀的手下，纳忠臣服。而在波涛汹涌的麻将历史长河中，拥有银色头发的赤木茂（本乡奏多 饰）注定是一个不可被忽视的重要人物。他虽然年纪轻轻，却拥有缜密冷静的头脑和胆识，甫一出场便挑败麻坛重量级人物，由此震惊黑道，并被冠名为“传说的麻将士”。与之相对，拥有黑白两道背景的鹫巢岩（津川雅彦 饰）正是傲立在麻坛顶点的“黑暗之王”，他创立“鹫巢麻将”不仅敛财无数，更借机除掉无数天资聪颖的麻坛新秀。为了攻破这个狡猾男人的防线，昭和40年的某个夏日，不良刑警安冈（神保悟志 饰）拜托赤木杀入鹫巢的巢穴。两代麻坛巨子注定要展开一场激烈的搏杀……
The following code:
脾气火爆的篮球名教罗伊在在输掉一场大学联盟比赛后被迫降级，去执教一只屡战屡败的高中球队。在第一堂课上，罗伊眼看着孩子们输掉109分，而且似乎这还不是最坏的……罗伊只能从最基本的东西开始教起，过人、抢篮板球、漏球、投篮，他似乎带给这个球队很多魔力，熔炼工球队也在他的带领下越打越顺，而罗伊也在教授这些孩子的过程中体会到了篮球带给他的那种久违的快乐……
……干杯。
Reference: Baidu Encyclopedia-Civil Aviation Pilots
