Rule Definition
There is no dispute that these comments contribute to a developer's understanding and help a developer write reliable applications more quickly. Without documenting methods it is dififcult for anyone else than the author to guess the purpose of the method except by looking at the code and eventually the code called by this method.

Remediation
You should add JavaDoc Comments for all methods (Except Private Methods,getters and setters, Empty Constructors and Methods overriding another method) of the application.

Violation Code Sample

public static String getName(String[] args) throws NoNameException {  //Violation     if(args.length == 0) {         throw new NoNameException();     } else {         return args[0];     } }

Fixed Code Sample

/**  * Extracts the user's name from the input arguments.  *  * Precondition: 'args' should contain at least one element, the user's name.  *  * @param  args            the command-line arguments.  * @return                 the user's name (the first command-line argument).  * @throws NoNameException if 'args' contains no element.  */ public static String getName(String[] args) throws NoNameException {     if(args.length == 0) {         throw new NoNameException();     } else {         return args[0];     } }

https://developer.atlassian.com/server/confluence/javadoc-standards/