How to correctly round a double to the nearest integer, tenths, hundredths, thousandths, or any decimal place in Java. The code handles both positive numbers, negative numbers, and zero, too.
How to generate all permutations of a given string using a Java recursive function
How to generate keypress events in Java using the Robot class.
How to encode a plain text string into appropriate HTML entities using Java. This method is similar to the htmlentities function in PHP.
How to implement a JSON based data interchange using an AJAX client-side request and a Java Servlet server-side response.