The Swing toolkit has a single golden rule: all long computations must be performed outside of the Event Dispatch Thread (or EDT for short). This rule also states that all interaction with UI components must be done inside the EDT, including building a component and reading/writing component properties. See Concurrency in Swing for more information.Often times this rule can be broken easily as there is no compile time check for it. The Swing toolkit offers a helper class SwingUtilities
that exposes a pair of method that let you run code inside the EDT, however there is no helper method for running code outside of the EDTSwingBuilder provides a few methods that let you build multi-threaded applications the easy way. These methods are available in Views and Controllers.