Compatibility with the latest Spring AMQP 2.0

Since Mockito cannot mock `final` methods, neither fields we get an `NPE` for the `final directReplyToContainers` in the `final RabbitTemplate.stop()`

* Change `mock()` to the `spy()` letting the real calls for the `final` methods.
* Fix `InboundEndpointTests` populating `Jackson2JsonMessageConverter` to the `RabbitTemplate`, because previously the stub method hasn't been called at all on the `mock` and we haven't known that there is no proper config for verification

spring-integration-amqp/src/test/java/org/springframework/integration/amqp/config/AmqpOutboundChannelAdapterParserTests.java

@@ -301,7 +301,7 @@ public class AmqpOutboundChannelAdapterParserTests {
 
 	@Test
 	public void testInt3430FailForNotLazyConnect() {
-		RabbitTemplate amqpTemplate = mock(RabbitTemplate.class);
+		RabbitTemplate amqpTemplate = spy(new RabbitTemplate());
 		ConnectionFactory connectionFactory = mock(ConnectionFactory.class);
 		RuntimeException toBeThrown = new RuntimeException("Test Connection Exception");
 		doThrow(toBeThrown).when(connectionFactory).createConnection();

spring-integration-amqp/src/test/java/org/springframework/integration/amqp/config/OutboundGatewayTests.java

@@ -22,6 +22,7 @@ import static org.junit.Assert.assertTrue;
 import static org.mockito.Matchers.anyString;
 import static org.mockito.Mockito.doAnswer;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.when;
 
 import org.junit.After;
@@ -95,7 +96,7 @@ public class OutboundGatewayTests {
 		when(context.getBean(IntegrationContextUtils.INTEGRATION_EVALUATION_CONTEXT_BEAN_NAME,
 				StandardEvaluationContext.class))
 			.thenReturn(evalContext);
-		RabbitTemplate template = mock(RabbitTemplate.class);
+		RabbitTemplate template = spy(new RabbitTemplate());
 		AmqpOutboundEndpoint endpoint = new AmqpOutboundEndpoint(template);
 		endpoint.setRoutingKeyExpression(PARSER.parseExpression("@foo"));
 		endpoint.setExchangeNameExpression(PARSER.parseExpression("@bar"));

spring-integration-amqp/src/test/java/org/springframework/integration/amqp/inbound/InboundEndpointTests.java

@@ -21,12 +21,17 @@ import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
+import static org.mockito.Matchers.any;
 import static org.mockito.Matchers.anyBoolean;
+import static org.mockito.Matchers.anyString;
 import static org.mockito.Mockito.doAnswer;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.when;
 
 import java.util.Map;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
 
 import org.junit.Test;
 import org.mockito.Mockito;
@@ -163,7 +168,10 @@ public class InboundEndpointTests {
 					.build();
 		}));
 
-		RabbitTemplate rabbitTemplate = Mockito.mock(RabbitTemplate.class);
+		RabbitTemplate rabbitTemplate = spy(new RabbitTemplate());
+		rabbitTemplate.setMessageConverter(new Jackson2JsonMessageConverter());
+
+		CountDownLatch sendLatch = new CountDownLatch(1);
 
 		Mockito.doAnswer(invocation -> {
 			org.springframework.amqp.core.Message message =
@@ -176,9 +184,11 @@ public class InboundEndpointTests {
 			assertFalse(headers.containsKey(JsonHeaders.TYPE_ID));
 			assertFalse(headers.containsKey(JsonHeaders.KEY_TYPE_ID));
 			assertFalse(headers.containsKey(JsonHeaders.CONTENT_TYPE_ID));
+			sendLatch.countDown();
 			return null;
-		}).when(rabbitTemplate).send(Mockito.anyString(), Mockito.anyString(),
-				Mockito.any(org.springframework.amqp.core.Message.class), Mockito.any(CorrelationData.class));
+		}).when(rabbitTemplate)
+				.send(anyString(), anyString(), any(org.springframework.amqp.core.Message.class),
+						any(CorrelationData.class));
 
 		AmqpInboundGateway gateway = new AmqpInboundGateway(container, rabbitTemplate);
 		gateway.setMessageConverter(new Jackson2JsonMessageConverter());
@@ -198,6 +208,7 @@ public class InboundEndpointTests {
 		ChannelAwareMessageListener listener = (ChannelAwareMessageListener) container.getMessageListener();
 		listener.onMessage(amqpMessage, rabbitChannel);
 
+		assertTrue(sendLatch.await(10, TimeUnit.SECONDS));
 	}