Java Memory Model

Java Memory Model

• https://en.wikipedia.org/wiki/Java_memory_model
• JSR-133(Java Specification Request 133)
• JSR-133 FAQ : http://www.cs.umd.edu/~pugh/java/memoryModel/jsr-133-faq.html#reordering
• What is a memory model, anyway? 
• Do other languages, like C++, have a memory model?
• What is JSR 133 about?
• What is meant by reordering?
• What was wrong with the old memory model?
• What do you mean by incorrectly synchronized?
• What does synchronization do?
• How can final fields appear to change their values?
• How do final fields work under the new JMM?
• What does volatile do?
• Does the new memory model fix the "double-checked locking" problem?
• What if I'm writing a VM?
• Why should I care?