- 1 What is the use of static in Java?
- 2 When would you use a static class?
- 3 Why Static is used in Java main method?
- 4 What is difference between final and static?
- 5 Can we override static method?
- 6 Why are static classes bad?
- 7 Can static class have constructor?
- 8 How do you use a static class?
- 9 Why we Cannot override static method?
- 10 Can we have 2 main methods in Java?
- 11 What if static is removed from main method?
- 12 Can static be final?
- 13 Can we inherit static method in Java?
- 14 Can a constructor be final?
What is the use of static in Java?
In Java, static keyword is mainly used for memory management. It can be used with variables, methods, blocks and nested classes. It is a keyword which is used to share the same variable or method of a given class. Basically, static is used for a constant variable or a method that is same for every instance of a class.
When would you use a static class?
The advantage of using a static class is that the compiler can check to make sure that no instance members are accidentally added. The compiler will guarantee that instances of this class cannot be created. Static classes are sealed and therefore cannot be inherited. They cannot inherit from any class except Object.
Why Static is used in Java main method?
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. Static method of a class can be called by using the class name only without creating an object of a class.
What is difference between final and static?
The main difference between a static and final keyword is that static is keyword is used to define the class member that can be used independently of any object of that class. Final keyword is used to declare, a constant variable, a method which can not be overridden and a class that can not be inherited.
Can we override static method?
Can we Override static methods in java? We can declare static methods with the same signature in the subclass, but it is not considered overriding as there won’t be any run-time polymorphism. Hence the answer is ‘No’.
Why are static classes bad?
Since classes with static methods have nothing to do with objects, they don’t know who they are, what they should do, and what they should not do. The boundaries are blurred, so we just write one instruction after another. It’s hard to stop until we’re done with our task.
Can static class have constructor?
in a static class. You can have a static constructor in a static class but you cannot have an instance constructor inside a static class.
How do you use a static class?
In C#, one is allowed to create a static class, by using static keyword. A static class can only contain static data members, static methods, and a static constructor.It is not allowed to create objects of the static class. Static classes are sealed, means you cannot inherit a static class from another class.
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 have 2 main methods in Java?
The only way to have two main methods is by having two different classes each with one main method. The name of the class you use to invoke the JVM (e.g. java Class1, java Class2) determines which main method is called.
What if static is removed from main method?
If you don’t add the ‘ static ‘ modifier in your main method definition, the compilation of the program will go through without any issues but when you’ll try to execute it, a “NoSuchMethodError” error will be thrown.
Can static be final?
Constant variables never change from their initial value. Static variables are stored in the static memory, mostly declared as final and used as either public or private constants.
Can we inherit static method in Java?
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. Static method is inherited in subclass but it is not polymorphism.
Can a constructor be final?
No, a constructor can ‘t be made final. A final method cannot be overridden by any subclasses. But, in inheritance sub class inherits the members of a super class except constructors. In other words, constructors cannot be inherited in Java therefore, there is no need to write final before constructors.