I remember poor, finishing this mind map, the equivalent of a more serious look at the whole mind map, basically is the original copy.
has a hierarchical relationship. And some of my own understanding. Because the image of the mind map to get out of the picture is greater than 100M. So let's release the source file,
Read and read more conveniently. Free integral download: http://download.csdn.net/detail/mr_zhuqiang/8945087 (I am very silent ah.) It used to be a free integral, not knowing when to become 5 points. Do not know how to modify into 0 points)
There are a few points I think are reading this book or mind mapping. What you need to understand is:
1. What is memory visibility
2. In Java programs, code directives executed at the bottom are not performed exactly in sequence-there are reordering
3. Volatile is a concept that is related to the number of bits of hardware and the number of digits in the data, and is actually irrelevant to multithreading.
Example: long:64 bit, Operation Long on 32-bit hardware requires two times (registers and memory), you can need volatile (multithreading) to ensure that the current thread is fully written to 64 bits, other threads can read or write on 64-bit hardware operation long (64 bits), With no volatile a little influence (machine instructions have ensured this)
If this is correct, then it validates the two characteristics of volatile, visibility and atomicity. However, if you want to use code to show the error effect, it seems not to write,
Useful volatile to ensure synchronicity. But this is indeed misused, volatile only to ensure that the variable read and write, does not guarantee the synchronization of the composite operation. So it's okay to remember the two features of volatile.
4. It is because of the reordering and data competition that there is multithreading concurrency security issues
5. What is escaping. : The object has not yet been constructed to complete the reference has been used elsewhere-called escape
The correct initialization method for the modified variable of 6.final
The following is an organized mind map level screenshot show
Download Address: http://download.csdn.net/detail/mr_zhuqiang/8939419