1. A method for testing an event processing system, comprising: reading in, by a testing framework, input events data, output events data, and a processing rule from a test file, wherein the test file is associated with a test schema that is designed for testing the event processing system; converting, by the testing framework, the input events data into a plurality of input event objects, wherein an event type of the event objects is specified in the test file; sending each of the input event objects in an event stream to an event processing system, wherein each said input event object is associated with a timestamp, and wherein the event stream is specified in the test file; providing, by the testing framework and to the event processing system, logic specified in a rule section of the test file; receiving, by the testing framework, an actual output event from the event processing system, wherein the actual output event is associated with a timestamp; constructing a corresponding internal representation object for the actual output event, wherein the internal representation object includes, as properties, the actual output event and the timestamp associated with the actual output event; and comparing the internal representation object in an event window with one or more expected output events for the event window.