Can static variables be volatile?

Yes, you can. A static variable in Java is stored once per class (not once per object, such as non-static variables are). Declaring a variable as volatile (be it static or not) states that the variable will be accessed frequently by multiple threads.

What does static volatile mean in Java?

Declaring a static variable in Java, means that there will be only one copy, no matter how many objects of the class are created. To avoid this you can declare the variable as static volatile and this will force the thread to read each time the global value.

What is difference between static and volatile?

A static variable is stored once per class. A static volatile variable is stored once per class and will be accessed frequently by multiple threads, i.e. reads cannot be cached. Even if you access a static value through multiple threads, each thread can have its local cached copy!

Is it bad to use static variables Java?

Static variables are generally considered bad because they represent global state and are therefore much more difficult to reason about. In particular, they break the assumptions of object-oriented programming.

How does volatile work in Java?

Since volatile keyword in Java only synchronizes the value of one variable between Thread memory and “ main ” memory while synchronized synchronizes the value of all variable between thread memory and “ main ” memory and locks and releases a monitor to boot.

What is volatile data type in Java?

Volatile keyword is used to modify the value of a variable by different threads. It is also used to make classes thread safe. It means that multiple threads can use a method and instance of the classes at the same time without any problem. The volatile keyword can be used either with primitive type or objects.

When should I use volatile in Java?

When to use it?

You can use a volatile variable if you want to read and write long and double variable automatically.
It can be used as an alternative way of achieving synchronization in Java.
All reader threads will see the updated value of the volatile variable after completing the write operation.

Do I need volatile with synchronized?

Effectively, a variable declared volatile must have it’s data synchronized across all threads, so that whenever you access or update the variable in any thread, all other threads immediately see the same value. Generally volatile variables have a higher access and update overhead than “plain” variables.

Is Java volatile thread safe?

Access to volatile int in Java will be thread-safe.

Why static method is bad?

The reason you are warned away from static methods is that using them forfeits one of the advantages of objects. Objects are intended for data encapsulation. This prevents unexpected side effects from happening which avoids bugs. Static methods have no encapsulated data* and so don’t garner this benefit.

Is using static a bad practice?

Static Methods/Variables are bad practice. In short: Yes. There are many disadvantages and static methods should almost never be used. Using static methods and variables breaks a lot of the power available to Object-Oriented code.

Is volatile synchronized?