This release of dyn4j was focused on performance and the API. Many API changes, both breaking and non-breaking, have been made. See the Release Notes for more details. Many new small features have been made as well. You can see them on the Features page or in the Release Notes.
The Sandbox app. reflects the changes above. The biggest change is the addition of the Help Contents. This will provide those unfamiliar with dyn4j with help on how to use the application.
When running the Sandbox application you may be asked to accept a certificate from me (I just self signed the JARs). The certificates will expire six months from today.
The Sandbox has no dependencies and requires Java 1.6 or higher.