iCal4j Connector is a tool that helps you manage iCalendar and vCard collections.
The connector includes multiple interfaces for interacting with collections of iCalendar and vCard data. A command line interface allows you to create, query and manipulate collections of data and output to mutliple formats for tool chaining support. The REST API uses the same underlying command pattern for the CLI to expose similar functions to HTTP-enabled clients. And the Java API provides support for the implementation of pluggable backends for integration with both standard and customized data sources using the same interface.