In Java, command line arguments refer to the values or parameters that are passed to a Java program when it is executed from the command line. These arguments are passed as strings separated by spaces and can be accessed by the Java program using the args parameter in the main method.

Here's an example Java program that demonstrates how to use command line arguments:

public class CommandLineArgumentsExample {
    public static void main(String[] args) {
        System.out.println("Number of arguments: " + args.length);
        System.out.println("Arguments: ");
        for (int i = 0; i < args.length; i++) {
            System.out.println(args[i]);
        }
    }
}

In this example, the main method simply prints out the number of arguments that were passed to the program, followed by the actual arguments themselves.

To run this program from the command line, compile it with the javac command:

javac CommandLineArgumentsExample.java

And then run it with some arguments:

java CommandLineArgumentsExample arg1 arg2 arg3

The output should be:

Number of arguments: 3
Arguments:
arg1
arg2
arg3

As you can see, the program receives the three arguments (arg1, arg2, and arg3) and prints them out one by one. You can pass any number of arguments to a Java program using the command line, and the program can access them and use them as needed.