Does every Java program must have a public class?

Is public class mandatory in Java?

java file without a public class. Okay, so a java source file must have at least one public class and the file should be called “class-name.

Does everything in Java have to be in a class?

The Java language assumes that you want to do only object-oriented programming. You cannot code anything in Java without declaring classes and objects. For example, if you have to say a small sentence “Hello World”, it should be declared as a class: class HelloWorldApp { public static void main(String[] args) { System.

What if there is no public class in Java?

If there is no public class in the source file then main method can lie in any class and we can give any name to the source file. If you are not following the first constraint then you will receive a compilation error saying “The public type A must be defined in its own file”.

Can there be 2 public classes in Java?

Long story short: no, you can’t put two public classes in one file because the compiler wouldn’t be able to handle that correctly.

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Can a Java file have 2 classes?

Yes ! . java file can contain only one public class. If you want these two classes to be public they have to be put into two .

What is class real time example?

Object is the concept which represents the class. … With the help of a new operator we may easily create object of class and memory is created in the HEAP and the object is called an instance of class. REAL TIME EXAMPLE. If animal is the class then dog is the object, if human is the class then man is the object.

What is a class and object?

a class describes the contents of the objects that belong to it: it describes an aggregate of data fields (called instance variables), and defines the operations (called methods). object: an object is an element (or instance) of a class; objects have the behaviors of their class.

Can constructor be inherited?

Constructors are not members, so they are not inherited by subclasses, but the constructor of the superclass can be invoked from the subclass.

What does Cannot find symbol mean in java?

The “cannot find symbol” error occurs mainly when we try to reference a variable that is not declared in the program which we are compiling, it means that the compiler doesn’t know the variable we are referring to.

Can’t find or load main method in java?

When you get the message “Could not find or load main class …”, that means that the first step has failed. The java command was not able to find the class. And indeed, the “…” in the message will be the fully qualified class name that java is looking for.

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How can we use two classes in java?

In general, Java has a main public class with a name that should match with the Java class file name and it calls other classes from this main class. The second approach is to write each class in different files and link them together with a package. In other words, all class files should be in the same class.

Why can’t we have two public classes in java?

There can be only one public class in a java file because the name of java file is same as the name of public class. And obviously we can’t have a file with two different names.

Which is not a java feature?

2) Which of the following is not a Java features? Explanation: The Java language does not support pointers; some of the major reasons are listed below: One of the major factors of not using pointers in Java is security concerns. Due to pointers, most of the users consider C-language very confusing and complex.

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