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:
《迷宫行者》讲述了男孩托马斯（Dylan O’Brien 饰演）醒来时发现自己身处一个由巨石组成的巨大迷宫Glade中，他只记得自己的名字，其他一切记忆全都失去了。和他一样在这个迷宫中的还有一些孩子，他们也同样不记得自己是怎么到这里的。每天早晨迷宫的大门会被打开，而到了晚上就会关闭，迷宫中有一种可怕生物叫做Grievers。每隔三十天，就会有一个新的男孩到来，但令人意外的是，在托马斯之后来的却是个女孩，她带来了令人惊讶的讯息：只有托马斯才能带领大家走出迷宫，而前提是托马斯必须首先解开埋藏在他记忆深处的黑暗秘密。
Yayao Town is located in Huadu District of Guangzhou City. People's living standard is still a long way from a well-off society. Their cultural level is not high. The education of young people is not perfect enough. The popularization and education of the masses are carried out slowly. Large areas of wasteland in the town have yet to be developed. All kinds of factories and enterprises are relatively small, but the infrastructure construction in the town has made necessary achievements. People's lives are still relatively stable, and everything needs to be developed and perfected in the construction work.
遥想当年祖师率兵征战之时，也该是这样的感悟。
两位看这样如何：如今天也晚了，病人也差不多都走了。
只要努力不懈梦想一定会实现──。现在只需要朝著那闪耀的目标，奋不顾身地勇往直前就行了！从此，少女们“ 大家一起实现的故事”（学园偶像计划）就此展开！
讲述了三位世界上最不幸的女性们一边被卷入麻烦中，一边为了抓住幸福而奋斗的故事。以财运为首，所有运气都为零的福良幸（25岁），男运和人际运都为零的朝仓香（31岁），工作运为零的现在没有工作的绫波树（35岁），这三个完全不走运的人，在彩票卖场的小骚动中相识。每次都会被卷入不幸的事件、纠纷、灾难中，但她们的命运都会被一个长着律师和占卜师面孔的神秘男子进一步改变。3人虽然像占卜所示那样行动，但却被卷入了更不幸的风暴中……
他终于意识到，自己一向小看所谓的心学与徐阶了。
Resource consumption class is a typical DDoS attack, the most representative include: Syn Flood, Ack Flood, UDP Flood. The target of this kind of attack is very simple, that is, to consume normal bandwidth and the ability of protocol stack to process resources through a large number of requests, thus achieving the purpose that the server cannot work normally.
Public class SourceSub1 implementations Sourceable {
在百子成功渡过地表入侵，山地基因危机，Ari智能危机以及天幕辐射危机的5年后，天空人和小oHeda领导的地表人又回到了地面。在重建家园的时候，意外发现大战前美国国防建立的海底智能化基地由于备用供电终止，浮出水面。在探索后发现，基地并没有幸存者。在修好了供电设备后，天空人进入了海底基地的控制系统，原来这是在冷战时期就开始研发的太空战基地，之所以修在海底是为了安全和保密。海底基地可以接入还在运行的军事卫星，意外发现美国已经偷偷和宇宙的神族文明取得了联系，神族文明的外交舰队已在百年前出发，现在已进入银河系的边缘。神族文明发现地球文明已经不复存在。同时ari当时备份在宇宙空间站的系统错误判定神族文明的来意，希望他们能帮助人类重建家园。然而神族文明却已开始了殖民地球的计划。外交舰队的任务是消灭地球残留文明建立新的秩序。天空人和地表人将如何利用地球倒退的文明击败宇宙神族将是本季的亮点。基本剧情设定，神族文明也是碳基生物，具有和人类相似的外形，其武器也是基于量子力学开发的，只不过比人类当年科技全胜的要先进。神族文明当年和地球文明互相发现后，认为地球文明的科技具有爆炸性，未必能在到达地球后仍保持技术领先，不过由于对于未知世界的好奇，他们派出了2艘星舰和1w名神族战士的外交舰队。
Conforming to the explosive growth of China's cultural and tourism industry, "Charming China City? The" City Alliance "was formally established. The alliance brings together the participating cities of "Charming China City" to build a cooperative and shared platform for the development of cultural and tourism industries. Ha Xuesheng, director of the program department of CCTV's financial channel, Tang Lin and Mei Xiangrong, producers of CCTV's financial channel "Charming China City", awarded licenses to members, directors and representatives of executive directors of the City Alliance.
K 'DASH
自从短暂的超级英雄生涯悲剧收场后，杰西卡·琼斯成为了纽约地狱厨房地区暴躁、尖刻的私家侦探，开始重塑自己的生活和事业。但由于深受严重的创伤后应激障碍的影响，杰西卡需要对抗外压、战胜心魔，必要时还得用到她那非凡的能力……尤其当她的生命受到威胁时。
这一动，可就不好了，葫芦高喊：敌人逃跑了——锥形阵中间的人也乖觉，他们暂时不用动手。
My judge said, 'If I told you what you said, would you believe it yourself?' When their leader came, he told me, 'haven't you told the truth yet?' , look at me also didn't reply, told me 'the somebody else said, the first to die is Xia Qiyong, right? You are the lightest, still hold the press? " He ordered me.
在温馨祥和的闯堂镇上，一场全镇居民期待已久的祈愿大会即将举行。闯堂兔和他的小伙伴们正在忙碌的准备着。就在此时，一个意外的发现让闯堂兔发现，似乎有一股黑暗的势力要破坏这场盛大的祈愿大会，更让人惊讶的是：这突如其来的危机，又与闯堂兔神秘失踪多年的父亲兔博士有着千丝万缕的联系。一段童趣荡漾而又精彩纷呈的快乐冒险就这样开始了……
抗日战争末期，阿尔山的原始森林遭到了日本侵略者疯狂的采伐。地下党员陈森海带领众人歼灭了日军，将被掠往日本大批木材又回到中国。
