Chapter 22.  Dynamic Plug-ins

Chapter 22. Dynamic Plug-ins Applications are often dynamic. New functions are added, old functions are removed, but the system keeps running. We saw this in Chapter 21, "Installing and Updating Plug-ins," with the dynamic installation of MUC capabilities into Hyperbola. The Eclipse Runtime and OSGi enable this kind of behavior and the RCP base plug-ins tolerate it, but the ability does not come freeyou must follow certain practices to make the most of these scenarios. This chapter discusses the unique challenges presented to plug-in writers as they attempt to handle the comings and goings of plug-ins in the environmentdynamic tolerance. We first look at Hyperbola as an example of dynamic tolerance. With that as a base, we identify some common dynamic plug-in scenarios and outline coding practices and designs for handling them. Throughout the discussion, the dynamic MUC example from Chapter 21 is used as an example of exploiting Eclipse's dynamic capabilities.