HystrixTest.java

@Test
public void should_execute_fallback_method_when_circuit_is_open() {
  
  //Initialize HystrixRequestContext to be able to get some metrics
  HystrixRequestContext context = HystrixRequestContext.initializeContext();
  HystrixCommandMetrics creditCardMetrics = HystrixCommandMetrics.getInstance(HystrixCommandKey.Factory.asKey(HelloWorldRestCommand.class.getSimpleName()));
  
  //We use Archaius to set the circuit as closed.
  ConfigurationManager.getConfigInstance().setProperty("hystrix.command.default.circuitBreaker.forceOpen", false);
  
  String successMessage = new HelloWorldRestCommand().execute();
  assertThat(successMessage, is("Hello World"));
  
  //We use Archaius to open the circuit
  ConfigurationManager.getConfigInstance().setProperty("hystrix.command.default.circuitBreaker.forceOpen", true);
  
  String failMessage = new HelloWorldRestCommand().execute();
  assertThat(failMessage, is("Good Bye"));
  
  //Prints Request => HelloWorldRestCommand[SUCCESS][19ms], HelloWorldRestCommand[SHORT_CIRCUITED, FALLBACK_SUCCESS][0ms] 
  System.out.println("Request => " + HystrixRequestLog.getCurrentRequest().getExecutedCommandsAsString());
  
  assertThat(creditCardMetrics.getHealthCounts().getTotalRequests(), is(2));
  assertThat(creditCardMetrics.getHealthCounts().getErrorCount(), is(1));

}