Compare and swap is an alternative to Java synchronized blocks when designing concurrent data structures or algorithms. A compare and swap operation first compares the value of a variable with an expected value, and if the values are equal, swaps the value of the variable with a new value. Compare and swap is abbreviated CAS. A compare and swap operation is atomic. Compare and swap is especially useful for check-then-act type code. You can use compare and swap operations to guard a critical section, or for optimisticl locking style concurrency. Chapters: 0:00 Compare and swap introduction 0:31 Compare and swap example 1:45 Compare and swap for check-then-act cases 5:45 Compare and swap used in a lock implementation 9:32 Compare and swap vs. Java synchronized blocks 17:59 Compare and swap as guard for critical section 18:59 Compare and swap for optimistic locking Compare and swap tutorial - text: http://tutorials.jenkov.com/java-concurrency/compare-and-swap.html Java Concurrency tutorial - text / video: http://tutorials.jenkov.com/java-concurrency/index.html https://www.youtube.com/playlist?list=PLL8woMHwr36EDxjUoCzboZjedsnhLP1j4 ... https://www.youtube.com/watch?v=ufWVK7CHOAk

Java annotations are used to provide meta data for your Java code. Java annotations can be used by the Java compiler, Java source code processors, or your Java applications. This Java annotations tutorial explains the basics of Java annotations. I have a second Java Annotations tutorial video explaining how to create your own custom Java Annotations here: https://www.youtube.com/watch?v=UlhtkjfxUUU Here is a textual version of this Java annotations tutorial: http://tutorials.jenkov.com/java/annotations.html ... https://www.youtube.com/watch?v=0VPRkVWkM70

The Java volatile keyword can be applied to Java variable declarations to force the Java VM to always read the variable value directly from main memory, and always write changes to the variable directly back to main memory immediately. Chapters 0:00 Java volatile introduction 0:41 Non-volatile variable visibility problems 2:27 Java volatile visibility guarantee 5:30 Instruction reordering could break the Java volatile visibility guarantee 12:33 Java volatile happens before guarantee 15:03 Java volatile performance overhead 15:56 Java volatile is not always enough Java Memory Model - JSR 133 https://www.cs.umd.edu/~pugh/java/memoryModel/jsr-133-faq.html Java volatile tutorial - textual: http://tutorials.jenkov.com/java-concurrency/volatile.html Java synchronized tutorial - textual / video: http://tutorials.jenkov.com/java-concurrency/synchronized.html https://www.youtube.com/watch?v=eKWjfZ-TUdo Java concurrency tutorial - textual: http://tutorials.jenkov.com/java-concurrency/index.html Java concurrency tutorial - playlist: https://www.youtube.com/playlist?list=PLL8woMHwr36EDxjUoCzboZjedsnhLP1j4 ... https://www.youtube.com/watch?v=nhYIEqt-jvY