A Java native language binding for Hoverfly, a Go proxy which allows you to simulate http services in your unit tests. Another term for this is Service Virtualisation.
Simulation of http/https services
Strict or loose http request matching based on URL, method, body and header combinations
Fluent and expressive DSL for easy generation of simulated services
Automatic marshalling of objects into JSON during request / response body generation
Create simulations by capturing live traffic
Hoverfly is a proxy, so you don’t need to alter the host that you make requests to
Multiple hosts / services per single instance of Hoverfly
Https automatically supported, no extra configuration required
Supports Mutual TLS authentication capture
Interoperable with standard Hoverfly JSON, making it easy to re-use data between Java and other native language bindings.
Use externally managed Hoverfly cluster for API simulations
Request verification
Response templating
Stateful capture / simulation
Full documentation is available here
<dependency> <groupId>io.specto</groupId> <artifactId>hoverfly-java</artifactId> <version>0.20.0</version> <scope>test</scope> </dependency>// Capture and output HTTP traffic to json file@ClassRulepublicstaticHoverflyRulehoverflyRule = HoverflyRule.inCaptureMode("simulation.json"); // After the capturing, switch to inSimulationMode to spin up a stub server@ClassRulepublicstaticHoverflyRulehoverflyRule = HoverflyRule.inSimulationMode(defaultPath("simulation.json")); // Or you can use both approaches at once. If json file not present in capture mode, if present in simulation mode@ClassRulepublicstaticHoverflyRulehoverflyRule = HoverflyRule.inCaptureOrSimulationMode("simulation.json");@ClassRulepublicstaticHoverflyRulehoverflyRule = HoverflyRule.inSimulationMode(dsl( service("www.my-test.com") .get("/api/bookings/1") .willReturn(created("http://localhost/api/bookings/1")) )); @TestpublicvoidshouldBeAbleToGetABookingUsingHoverfly(){// WhenfinalResponseEntity<String> getBookingResponse = restTemplate.getForEntity("http://www.my-test.com/api/bookings/1", String.class); // ThenassertEquals(bookFlightResponse.getStatusCode(), CREATED); assertEquals(bookFlightResponse.getHeaders().getLocation(), "http://localhost/api/bookings/1")}Some code examples for the DSL are available here.
More code examples for the DSL using request matchers can be found here.
// Verify that at least one request to a specific endpoint with any query paramshoverflyRule.verify(service(matches("*.flight.*")).get("/api/bookings").anyQueryParams(), atLeastOnce()); // Verify that an external service/dependency was not calledhoverflyRule.verifyZeroRequestTo(service(matches("*.flight.*"))); // Verify all the stubbed requests were made at least oncehoverflyRule.verifyAll();Contributions are welcome!
To submit a pull request you should fork the Hoverfly-Java repository, and make your change on a feature branch of your fork.
As of v0.10.2, hoverfly binaries are no longer stored in the repository. You should run ./gradlew clean test once to cache the binaries for development with your IDE.
If you have forked this project prior to v0.10.2, please re-fork to get a slimmer version of the repository.
Apache License version 2.0.
(c) iOCO 2025.