How to write and run Hello world program in Java?

QuickStart

Every program must begin with the class name, and the class must match the filename.

Hello world program

In above program, First class is created and file is saved as First.java same as class name.

Now, to run the program First.java, we need to compile it and it will run

To compile the java file, open cmd and locate the java file.

Type: javac filename.java

This will compile the java file and class file will be created

Now to run the java file.

Type: java filename

We can write java code in IDE such as VS code, Intellj Idea, to write and run the program.

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