Can I declare local variable as static?

In Java, a static variable is a class variable (for whole class). So if we have static local variable (a variable with scope limited to function), it violates the purpose of static. Hence compiler does not allow static local variable.

What would happen if we declared a local variable as static local?

When applied to a local variable, the static keyword defines the local variable as having static duration, meaning the variable will only be created once, and will not be destroyed until the end of the program.

Can we have static local variable in Java?

Unlike C, C++, Java does not allow static local variables. The compiler will throw the compilation error.

Can we declare local variable as final?

final is the only allowed access modifier for local variables. final local variable is not required to be initialized during declaration. final local variable allows compiler to generate an optimized code. final local variable can be used by anonymous inner class or in anonymous methods.

Are local variables static or dynamic in Java?

The Local variables and Instance variables are together called Non-Static variables.

Can we declare local variable as static? || Java interview Questions(2021)

Are static local variables bad?

Are static local variables bad practice? No. Static local variables differ in exactly one regard to non-local private variables: they have a smaller scope. Since you always want to keep scope as small as possible (= better encapsulation), local statics can be advantageous over private variables.

When should a static local variable be used?

Static local variables are useful when we want to have only one instance of our object in the local scope, which means all calls to the function will share the same object. The same can also be achieved by using global variables or static member variables.

Can a variable be local and static at the same time explain?

No a variable can't be static as well as local at the same time. Defining a local variable as static gives compilation error.

Can constructor be static?

A static constructor is used to initialize any static data, or to perform a particular action that needs to be performed only once. It is called automatically before the first instance is created or any static members are referenced.

Why main () method is declared as static?

The main() method is static so that JVM can invoke it without instantiating the class. This also saves the unnecessary wastage of memory which would have been used by the object declared only for calling the main() method by the JVM.

Can I have same name for local and static variable?

Therefore it is possible. Neither of the local static int sVar; will be allocated on the stack (if there is such a concept at all), each function body is a separate block, which limits the scope of the local static variable. The compiler uses a renaming scheme to ensure these variables are distinct at link time.

Can a local variable be static in C?

A local static variable is a variable, whose lifetime doesn't stop with a function call where it is declared. It extends until the lifetime of a complete program. All function calls share the same copy of local static variables.

What is the difference between local variable and static variable?

Local variables are non existent in the memory after the function termination. However static variables remain allocated in the memory throughout the life of the program irrespective of whatever function.

What is the lifetime of static local variable in C?

The space for the static variable is allocated only one time and this is used for the entirety of the program. Once this variable is declared, it exists till the program executes. So, the lifetime of a static variable is the lifetime of the program.

Is local static variable thread safe?

So yes, you're safe.

Are local variables thread safe in C?

Local variables are stored on the stack, each thread has a reference to its own set of variables on the stack, so local variables are thread safe. Yes.

Why static variables are bad?

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.

Where local static variables are stored?

The static variables are stored in the data segment of the memory. The data segment is a part of the virtual address space of a program. All the static variables that do not have an explicit initialization or are initialized to zero are stored in the uninitialized data segment( also known as the BSS segment).

Should global variables be static?

If global variable is to be visible within only one . c file, you should declare it static. If global variable is to be used across multiple . c files, you should not declare it static.

Can a static variable be changed?

Static methods cannot access or change the values of instance variables or the this reference (since there is no calling object for them), and static methods cannot call non-static methods. However, non-static methods have access to all variables (instance or static) and methods (static or non-static) in the class.

Is Auto local variable?

In computer programming, an automatic variable is a local variable which is allocated and deallocated automatically when program flow enters and leaves the variable's scope. The scope is the lexical context, particularly the function or block in which a variable is defined.

What is difference between local static and global static variables?

The difference between static global variables and static local variables is that a static global variable can be accessed from anywhere inside the program while a static local variable can be accessed only where its scope exists (i.e block scope).

Is extern a local variable?

The answer is yes. scope (visibility) and storage are two independent and connected concept. Here, x is one local variable (scope), and it's only visible within this block. extern dictates the storage, meaning this is merely one declaration, this variable is defined somewhere else.

Can we increment static variable in C?

Your static_var is equivalent to a file-scope variable ("global variable" if you will), which is created (with initial value of 5 ) only once when your program starts. That variable lives forever and forever keeps its last value. That's why you see it incremented continuously every time you enter the function.

What will happen if a programmer declares a global variable and a local variable with the same name?

It is usually not a good programming practice to give different variables the same names. If a global and a local variable with the same name are in scope, which means accessible, at the same time, your code can access only the local variable.