What happens if there is no main method in Java?
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What happens if there is no main method in Java?
If your program doesn’t contain the main method, then you will get an error “main method not found in the class”. It will give an error (byte code verification error because in it’s byte code, main is not there) not an exception because the program has not run yet.
Can a Java program run without class?
6 Answers. Yes, you need at least one class to have a program, but no, you do not need any methods (contrary to some other answers). EDIT : From Java 7 the above code with just static block and no main method does not produce any output.
What is required to run a Java program?
you will need a Java Runtime Environment (JRE) to run java programs. But if you want to learn java and develop your own programs, then you will need a Java Development Kit (JDK). The JDK includes the JRE and the java bytecode compiler to compile your sourcecode. You can download both here.
Can you run a code before executing main method?
Yes, code written in static initializer block is executed before calling the main method, but you won’t be able to run a class by using Java command, or Eclipse, or anything else, until it got public static void main(String args[]) method on it.
Can we have 2 main methods in Java?
Yes, you can have as many main methods as you like. You can have main methods with different signatures from main(String[]) which is called overloading, and the JVM will ignore those main methods. You can have one public static void main(String[] args) method in each class.
Is main class mandatory in Java?
3 Answers. Not all Java applications require a main method. Java can also be used to create web applications, for instance, which don’t require main methods to run. The only requirement that Java has, is that the signature of the method is correct.
Can any computer run Java?
Answer: Java can run on any machine with a JVM. JVM(Java Virtual Machine) acts as a run-time engine to run Java applications. JVM is a part of the JRE(Java Runtime Environment).
Where we can run Java program?
Type ‘javac MyFirstJavaProgram. java’ and press enter to compile your code. If there are no errors in your code, the command prompt will take you to the next line (Assumption: The path variable is set). Now, type ‘ java MyFirstJavaProgram ‘ to run your program.
Why TestNG has no main method?
Because the main() method is needed to run the Java program and while writing tests in TestNg we don’t use main() method, and we use Annotations instead. Annotations in TestNG are lines of code that can control how the method below them will be executed.