java并发,java内存模型,java锁
https://github.com/CyC2018/CS-Notes/blob/master/notes/Java%20%E5%B9%B6%E5%8F%91.md#%E4%B8%80%E7%BA%BF%E7%A8%8B%E7%8A%B6%E6%80%81%E8%BD%AC%E6%8D%A2
悲观锁和乐观锁
https://blog.csdn.net/niejiangnan9235/article/details/75649193
java并发,java内存模型,java锁
https://github.com/CyC2018/CS-Notes/blob/master/notes/Java%20%E5%B9%B6%E5%8F%91.md#%E4%B8%80%E7%BA%BF%E7%A8%8B%E7%8A%B6%E6%80%81%E8%BD%AC%E6%8D%A2
悲观锁和乐观锁
https://blog.csdn.net/niejiangnan9235/article/details/75649193