Quartz is a full-featured, open source job scheduling system that can be integrated with, or used along side virtually any j2ee or j2se application - from the smallest stand-alone application to the largest e-commerce system. quartz can be used to create simple or complex schedules for executing tens, hundreds, or even tens-of-thousands of jobs; jobs whose tasks are defined as standard java components or ejbs. the quartz scheduler includes many enterprise-class features, such as jta transactions and clustering.