GH-2366 Fix failing test on Mac

Resolves #2366

Author: boaty82

spring-integration-ip/src/test/java/org/springframework/integration/ip/tcp/connection/ConnectionEventTests.java

@@ -316,7 +316,20 @@ public void publishEvent(Object event) {
 
 	@Test
 	public void testFailConnect() {
-		TcpNetClientConnectionFactory ccf = new TcpNetClientConnectionFactory("junkjunk", 1234);
+		AbstractClientConnectionFactory ccf = new AbstractClientConnectionFactory("junkjunk", 1234) {
+
+			@Override
+			protected boolean isActive() {
+				return true;
+			}
+
+			@Override
+			protected TcpConnectionSupport buildNewConnection() throws Exception {
+				throw new UnknownHostException("Mocking for test ");
+			}
+
+		};
+
 		final AtomicReference<ApplicationEvent> failEvent = new AtomicReference<ApplicationEvent>();
 		ccf.setApplicationEventPublisher(new ApplicationEventPublisher() {