How do I open a .jar file?
Can class be public in java?
A public class is available for use by all other classes. … For example, if you write an ATMController program in some remote corner of cyberspace, then your ATMController program can contain code, such as myAccount. balance = 24.02, making use of the Account class declared.
Why do we use public?
public is used as an access modifier for a main method . static is used so that it can directly load in memory with creating any instance. void is used because it done not return any value and main is the entry point of program.
What is difference between public class and normal class in java?
Private members cannot be accessed from non-child class of same package. Public members can be accessed from child class of outside package. Private members cannot be accessed from child class of outside package. Public members can be accessed from non-child class of outside package.
Should classes be private in java?
Answer: We can not declare top level class as private. Java allows only public and default modifier for top level classes in java.
Is Main a keyword in Java?
main: It is the name of Java main method. It is the identifier that the JVM looks for as the starting point of the java program. It’s not a keyword.
What is private keyword in Java?
The private keyword is an access modifier used for attributes, methods and constructors, making them only accessible within the declared class.
Should method be public or private?
The rule is that a method should be made provided unless it is needed. One of the main reasons for this is that in a future release of an API etc., you can always make a private function public, but you can almost never make a previous public function private without breaking existing code.
Can we override main method in java?
No, we cannot override main method of java because a static method cannot be overridden. … So, whenever we try to execute the derived class static method, it will automatically execute the base class static method. Therefore, it is not possible to override the main method in java.
What is the difference between private and protected in java?
The private modifier specifies that the member can only be accessed in its own class. The protected modifier specifies that the member can only be accessed within its own package (as with package-private) and, in addition, by a subclass of its class in another package.
Why is public/private Java?
public means you can access it anywhere while private means you can only access it inside its own class. Just to note all private, protected, or public modifiers are not applicable to local variables in Java. a local variable can only be final in java.
Can we declare constructor as private?
Yes, we can declare a constructor as private. If we declare a constructor as private we are not able to create an object of a class. We can use this private constructor in the Singleton Design Pattern.
Can I create a private class in Java?
Private classes are allowed, but only as inner or nested classes. If you have a private inner or nested class, then access is restricted to the scope of that outer class.
Can Java class be static?
Can a class be static in Java ? The answer is YES, we can have static class in java. In java, we have static instance variables as well as static methods and also static block. Classes can also be made static in Java.