Slip Warm Design On Slippers Comfy amp; Bear Horse Plush for Sleepy Women's UwqPRSEP
Design amp; Women's for Slip Slippers On Sleepy Horse Warm Bear Plush Comfy
It's probably fair to say that on the whole, the volatile keyword in Java is poorly documented, poorly understood, and rarely used. To make matters worse, its formal definition actually changed as of Java 5. On this and the following pages, we will cut through this mess and look at what the Java volatile keyword does and when it is used. We will also compare it to other mechanisms available in Java which perform similar functions but under subtly different other circumstances.
What is the Java volatile keyword?
Essentially, volatile is used to indicate that a variable's value will be modified by different threads.
Declaring a volatile Java variable means:
The value of this variable will On Slip Horse Women's Plush for amp; Design Warm Sleepy Slippers Bear Comfy never be cached thread-locally: all reads and writes will go straight to "main memory";
Access to the variable acts as though it is enclosed in a synchronized block, synchronized on itself.
We say "acts as though" in the second point, because to the programmer at least (and probably in most JVM implementations) there is no actual lock object involved. Here is how synchronized and Plush On Warm Women's amp; Bear Comfy for Design Horse Slippers Slip Sleepy volatile compare:
Type of variable
Object or primitive
Women's Bear Design Horse Slip for Comfy Slippers amp; Sleepy Warm Plush On No
In other words, the main differences between synchronized and volatile are:
a primitive variable may be declared volatile (whereas you can't synchronize on a primitive with synchronized);
an access to a volatile variable never has the potential to block: we're only ever doing a simple read or write, so unlike a synchronized block we will never hold on to any lock;
because accessing a volatile variable never holds a lock, it is not suitable for cases where we want to read-update-write as an atomic operation (unless we're prepared to "miss an update");
a volatile variable that is an object reference may be null (because you're effectively synchronizing on the reference, not the actual object).
Attempting to synchronize on a null object will throw a NullPointerException.
Volatile variables in Java 5
We mentioned that in Java 5, the meaning of volatile has been tightened up. We'll come back to this issue in a moment. First, we'll look at a typical example of using volatile. Later, we'll look at topics such as:
Pamper yourself or your love ones with our cute & adorable sleepy Cow animal plush design slip-on slippers
UNPRECEDENTED COMFORT - Ultra-soft fibers coddle feet with warmth and gentle texture, while the non-slip weatherproof rubber soles adds maximum traction with any surface. The cloud-like lining and improved, flexible sole will give your feet total relaxation throughout the year.
WHY SO COMFORTABLE? - The completely improved insole is constructed with 3 layers of memory foam and sponge to provide superior comfortability. The soft plush lining will let you feel like you're walking on a cloud, while the cashmere-like knit upper will hold your feet in all right places.
GREAT HOUSE SLIPPER CHOICE - The soft plush fleece collar and lining with its exquisitely knitted upper reflect a look of luxury. They are not just for indoors. The side-seamed outsole prevents water and dampness from absorbing into these slippers allowing you to wear them outdoors if you so desire. They are both hand or machine washable.
SIZE OPTIONS - Available in multiple sizes, these stylish slippers fit most standard foot sizes.