Hello Java Program

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Hello Java Program

To run a simple "Hello, World!" program in Java, you'll need a few things. Here are the steps required:

Requirements:

1. Java Development Kit (JDK): Ensure you have the JDK installed on your computer. You can download it from the Oracle website or use OpenJDK, an open-source alternative. 

Steps to run the "Hello, World!" program:

1. Install Java Development Kit (JDK):  Download and install the JDK suitable for your operating system.

 2.Write the Java code:  Use a text editor or an Integrated Development Environment (IDE) like IntelliJ IDEA, Eclipse, or NetBeans to write your Java code.

 3.Write the "Hello, World!" program:

 Open a text editor and create a new file. Enter the Java code for the "Hello, World!" program. Here is the code:

4.Save the file:  Save the file with the name HelloWorld.java.

5.Open a terminal (Command Prompt or Terminal): Navigate to the directory where the HelloWorld.java file is saved.

6.Compile the Java code: In the terminal, use the javac command to compile the Java code:


This will generate a HelloWorld.class file in the same directory.

7.Run the compiled program: Once the code is compiled, you can run the program using the java command:

Running this command will execute the Java program, and you should see the output Hello, World! printed in the terminal.

Explanation of the code:

  • public:  It's an access modifier that allows the class to be accessed from anywhere. In Java, it's used to declare the visibility of classes, methods, and variables.
  • class:  This keyword is used to declare a class in Java. A class is a blueprint for objects.
  • HelloWorld: It's the name of the class. In Java, the class name must match the file name in which it is defined.
  • static: It allows the method to be accessed without creating an instance of the class. static methods can be called directly using the class name.
  • void: It is the return type of the method main(). void indicates that the method does not return any value.
  • main: It is the name of the method. In Java, the main method is the entry point for any Java program.
  • String[] args: This is the parameter passed to the main method. It's an array of strings used to pass arguments from the command line to the Java program.
  • System. out. println(): System is a predefined class in Java. out is an instance of the PrintStream class and println() is a method used to print a line to the console.
  • "Hello, World!": This is a string literal, a sequence of characters enclosed in double quotes. In this case, it's the text that will be printed to the console.