1. A method for injecting a fault into a stream operator in a data stream processing application, the method comprising: developing a fault injection operator having specialized logic to emulate an effect of a failure, the fault injection operator corresponding to a fault model, wherein the fault injection operator is a bursty tuple loss fault injection operator; embedding the fault injection operator into a data flow graph for the data stream processing application, so as to emulate at least one possible effect of the fault model on the data stream processing application, wherein the embedding comprises: embedding the fault injection operator immediately after each source operator in the data flow graph; embedding the fault injection operator immediately before each operator in the data flow graph that contains an upstream operator that produces more than one output stream; embedding the fault injection operator immediately before each operator in the data flow graph that consumes more than one input stream; and embedding the fault injection operator immediately before each operator in the data flow graph that has a stateful upstream operator; wherein the fault injection operator is embedded only in one or more positions of the data flow graph at which the fault model manifests, and wherein the fault injection operator emulates a different failure when embedded at each of the one or more positions in the data flow graph.