Introduction to plugins

A plugin is a piece of software that can be "plugged into" a software system without any modification of this system. Opinio provides the framework that makes this possible. Plugins was implemented to make Opinio more extensible and customizable. No matter how much functionality is included in the product, there are always some special features needed by various users.

The plugin framework imposes certain requirements that the plugin must meet, but no restrictions on the design on what type of functionality this plugin can offer. This section describes what a plugin must do, in order to meet this requirements.

To write a plugin, Java skills are required. Some time must also be spent to understand how Opinio works. This knowledge is done by using the product, and looking through the plugin API (included in the Opinio distribution).

The plugin API is limited to the method calls that was regarded as useful to plugin developers. There is even more functionality available in Opinio, but not yet offered through the Plugin API. ObjectPlanet welcomes any suggestions to improve or extend this API, if the suggested change is reasonable. Please let us know, and we will gladly consider your suggestions. Please go here to let us know:


Writing a plugin puts great responsibility in the hands of the plugin author. A small and simple plugin can potentially break the stability of the entire system. The Plugin API must be understood before using it. And before you go live using the plugin, test it well. Then test it again.