/** and /* in Java Comments

Question

What\'s the difference between

/**
 * comment
 *
 *
 */

and

/*
 * 
 * comment
 *
 */

in Java? When shou

Answer 1

Comments in the following listing of Java Code are the greyed out characters:

/** 
 * The HelloWorldApp class implements an application that
 * simply displays "Hello World!" to the standard output.
 */
class HelloWorldApp {
    public static void main(String[] args) {
        System.out.println("Hello World!"); //Display the string.
    }
}

The Java language supports three kinds of comments:

/* text */

The compiler ignores everything from /* to */.

/** documentation */

This indicates a documentation comment (doc comment, for short). The compiler ignores this kind of comment, just like it ignores comments that use /* and */. The JDK javadoc tool uses doc comments when preparing automatically generated documentation.

// text

The compiler ignores everything from // to the end of the line.

Now regarding when you should be using them:

Use // text when you want to comment a single line of code.

Use /* text */ when you want to comment multiple lines of code.

Use /** documentation */ when you would want to add some info about the program that can be used for automatic generation of program documentation.