A series of test cases that show techniques to test Spring Integration applications. Examples ======== ...spelchain.SpelChainTests.java This test case shows how to test a fragment of a larger integration flow. In this example, we have a simple chain containing a header enricher and a transformer. It uses Direct channels. The test case shows how to bridge the output channel to a queue channel so we can retrieve the output message after the test executes and verify the appropriate actions were applied to the input message. ...splitter.CommaDelimitedSplitterTests.java This test case shows both unit testing a custom splitter class as well as testing it within a Spring Integration flow fragment. ...aggregator.CommaDelimitedAggregatorTests.java This test case shows both unit testing a custom aggregator class as well as testing it within a Spring Integration flow fragment. ...aggregator.ExternalGatewaySubstitutionTests.java This example is a little more complex. The application is simplified version of a travel demo presented at SpringOne in 2010. You do not need to fully understand the application for the purposes of this demonstration. Suffice it to say that a zip code is sent to two outbound gateways (one web service, one http) and the weather and traffic for that zip code are aggregated together. You can run the "real" application by executing the Main class in src/main/java and entering a valid zip code in the console. In many cases, when integrating with external services, we can't rely on those services being available while we test. Consequently, we need a mechanism to stub out those services so we can run the remainder of the flow in a repeatable manner without need for connectivity to the services. This example uses dummy service activators in place of the real outbound gateways. This separation of 'infrastructure' from application beans is similar to the way we separate DataSource, ConnectionFactory beans etc so that the application can be tested with local versions.