When Would You Use A Static Block?

Why you Cannot override static method?

No, you cannot override static method in Java because method overriding is based upon dynamic binding at runtime and static methods are bonded using static binding at compile time..

Why static block is executed before main method?

Static block in java is executed before main method. … Static block in java initializes when class load into memory , it means when JVM read the byte code. Initialization can be anything; it can be variable initialization or anything else which should be shared by all objects of that class.

Can we declare static variable in static Block?

You can declare a variable static inside a static block because static variables and methods are class instead of instance variable and methods. This means that you wont be able to see a static field inside a method because it will be inside an inner scope and won’t be a class variable at all…

Can constructor be static?

No, we cannot define a static constructor in Java, If we are trying to define a constructor with the static keyword a compile-time error will occur. In general, static means class level. A constructor will be used to assign initial values for the instance variables.

Why we Cannot override static method?

Overloading is the mechanism of binding the method call with the method body dynamically based on the parameters passed to the method call. Static methods are bonded at compile time using static binding. Therefore, we cannot override static methods in Java.

Can we execute a program without main () method in Java?

Yes, we can execute a java program without a main method by using a static block. Static block in Java is a group of statements that gets executed only once when the class is loaded into the memory by Java ClassLoader, It is also known as a static initialization block.

Can we create object in Static Block?

The static block is a static initializer (a class initializer). You can use it to initialize a class or to do some logic during class load. … For instance, with static initializers you can initialize a map with db data to be used later during object instantiation.

Why static methods are bad?

They don’t have to be bad, but they are dangerous, because they are used incorrectly. There are only two situations when static methods or variables are being used and it’s not an abomination. Declaring a true global constant, not a global variable. … Static methods are a valuable and valid method of object creation.

When would you use a static initialization block?

Instance variables are initialized using initialization blocks. However, the static initialization blocks can only initialize the static instance variables. These blocks are only executed once when the class is loaded.

Is static block executed before Main?

Static Block and main() method in Java In Java static block is used to initialize the static data members. Important point to note is that static block is executed before the main method at the time of class loading. … Answer: No since JDK 1.7 it is not possible to execute any java class without main() method.

Are static methods inherited?

Static methods are inherited in Java but they don’t take part in polymorphism. If we attempt to override the static methods they will just hide the superclass static methods instead of overriding them. This concept is not that easy as it looks. … We can access static members by extending the parent class also.

Can final static method be overloaded?

Static methods cannot be overridden because they are not dispatched on the object instance at runtime. The compiler decides which method gets called. Static methods can be overloaded (meaning that you can have the same method name for several methods as long as they have different parameter types).

What will happen if we call main method in Static Block?

Because it is a bad idea. There are few occasions where static init blocks are useful – but they are definitely not a mean to trigger a complete main() and God knows what else! You see: these blocks get executed most likely at load time. This means that you have almost no control when exactly that happens.

Can we override static method?

Can we Override static methods in java? We can declare static methods with same signature in subclass, but it is not considered overriding as there won’t be any run-time polymorphism. Hence the answer is ‘No’.

What is the use of static methods in interface?

Java interface static method helps us in providing security by not allowing implementation classes to override them. We can’t define interface static method for Object class methods, we will get compiler error as “This static method cannot hide the instance method from Object”.

Why is main method static?

Java main() method is always static, so that compiler can call it without the creation of an object or before the creation of an object of the class. In any Java program, the main() method is the starting point from where compiler starts program execution. So, the compiler needs to call the main() method.

When would you use a static method?

You should use static methods whenever,The code in the method is not dependent on instance creation and is not using any instance variable.A particular piece of code is to be shared by all the instance methods.The definition of the method should not be changed or overridden.More items…•

How many times static block is executed in Java?

Unlike C++, Java supports a special block, called static block (also called static clause) which can be used for static initializations of a class. This code inside static block is executed only once: the first time the class is loaded into memory.