A query builder is a class that

1. implements the QueryBuilderPlugin interface
2. has the @PluginImplementation annotation

When implementing the interface you have to provide a short name, a caption and a callback function that creates new Vaadin components. You get an object of the type QueryController which you can use to set new queries from your component.

A query builder plugin must be either registered in the addCustomUIPlugins() function of the SearchUI (if the plugin is part of the annis-gui project) or must be added to a JAR-file that is located at one of the following locations:

• the plugins folder inside the deployed web application
• the path defined in the ANNIS_PLUGINS environment variable

Please also note that it is possible to configure a default query builder for an instance. Further information can be found in the User Guide.