Use @EnableModule(Channels.class) instead of field declarations

Standard channel interface types of Sink, Source, Processor
are provided, but user can create others with @Input and
@Output MessageChannel methods.

To get the declared channels in an app you can use the
@ModuleChannels qualifier to inject the interface, e.g.
@ModuleChannels(Cafe.class) injects the channels defined
in the Cafe.

spring-cloud-stream-samples/double/src/main/java/config/SinkModuleDefinition.java

@@ -18,25 +18,20 @@ package config;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
 import org.springframework.cloud.stream.annotation.EnableModule;
-import org.springframework.cloud.stream.annotation.Input;
+import org.springframework.cloud.stream.annotation.Sink;
 import org.springframework.integration.annotation.ServiceActivator;
-import org.springframework.messaging.MessageChannel;
 
 /**
  * @author Dave Syer
  * @author Marius Bogoevici
  */
-@EnableModule
+@EnableModule(Sink.class)
 public class SinkModuleDefinition {
 
 	private static Logger logger = LoggerFactory.getLogger(SinkModuleDefinition.class);
 
-	@Input
-	public MessageChannel input;
-
-	@ServiceActivator(inputChannel="input")
+	@ServiceActivator(inputChannel=Sink.INPUT)
 	public void loggerSink(Object payload) {
 		logger.info("Received: " + payload);
 	}

spring-cloud-stream-samples/double/src/main/java/config/SourceModuleDefinition.java

@@ -21,29 +21,25 @@ import java.util.Date;
 
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.cloud.stream.annotation.EnableModule;
-import org.springframework.cloud.stream.annotation.Output;
+import org.springframework.cloud.stream.annotation.Source;
 import org.springframework.context.annotation.Bean;
 import org.springframework.integration.annotation.InboundChannelAdapter;
 import org.springframework.integration.annotation.Poller;
 import org.springframework.integration.core.MessageSource;
-import org.springframework.messaging.MessageChannel;
 import org.springframework.messaging.support.GenericMessage;
 
 /**
  * @author Dave Syer
  * @author Marius Bogoevici
  */
-@EnableModule
+@EnableModule(Source.class)
 public class SourceModuleDefinition {
 
 	@Value("${format:YYYY/MM/dd hh:mm:ss}")
 	private String format;
 
-	@Output
-	public MessageChannel output;
-
 	@Bean
-	@InboundChannelAdapter(value = "output", autoStartup = "false", poller = @Poller(fixedDelay = "${fixedDelay}", maxMessagesPerPoll = "1"))
+	@InboundChannelAdapter(value = Source.OUTPUT, autoStartup = "false", poller = @Poller(fixedDelay = "${fixedDelay}", maxMessagesPerPoll = "1"))
 	public MessageSource<String> timerMessageSource() {
 		return () -> new GenericMessage<>(new SimpleDateFormat(this.format).format(new Date()));
 	}

spring-cloud-stream-samples/sink/src/main/java/sink/LogSink.java

@@ -18,25 +18,20 @@ package sink;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
 import org.springframework.cloud.stream.annotation.EnableModule;
-import org.springframework.cloud.stream.annotation.Input;
+import org.springframework.cloud.stream.annotation.Sink;
 import org.springframework.integration.annotation.ServiceActivator;
-import org.springframework.messaging.MessageChannel;
 
 /**
  * @author Dave Syer
  *
  */
-@EnableModule
+@EnableModule(Sink.class)
 public class LogSink {
 
 	private static Logger logger = LoggerFactory.getLogger(LogSink.class);
 
-	@Input
-	public MessageChannel input;
-
-	@ServiceActivator(inputChannel="input")
+	@ServiceActivator(inputChannel=Sink.INPUT)
 	public void loggerSink(Object payload) {
 		logger.info("Received: " + payload);
 	}

spring-cloud-stream-samples/sink/src/test/java/demo/ModuleApplicationTests.java

@@ -1,11 +1,21 @@
 package demo;
 
+import static org.junit.Assert.assertNotNull;
+
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.springframework.test.annotation.DirtiesContext;
-import org.springframework.test.context.web.WebAppConfiguration;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.SpringApplicationConfiguration;
+import org.springframework.cloud.stream.annotation.ModuleChannels;
+import org.springframework.cloud.stream.annotation.Output;
+import org.springframework.cloud.stream.annotation.Sink;
+import org.springframework.cloud.stream.annotation.Source;
+import org.springframework.messaging.MessageChannel;
+import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.web.WebAppConfiguration;
+
+import sink.LogSink;
 
 @RunWith(SpringJUnit4ClassRunner.class)
 @SpringApplicationConfiguration(classes = SinkApplication.class)
@@ -13,8 +23,19 @@ import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 @DirtiesContext
 public class ModuleApplicationTests {
 
+	@Autowired
+	@ModuleChannels(LogSink.class)
+	private Sink sink;
+
+	@Autowired
+	private Sink same;
+
+	@Output(Source.OUTPUT)
+	private MessageChannel output;
+
 	@Test
 	public void contextLoads() {
+		assertNotNull(this.sink.input());
 	}
 
 }

spring-cloud-stream-samples/source/src/main/java/source/TimeSource.java

@@ -19,12 +19,11 @@ package source;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.cloud.stream.annotation.EnableModule;
-import org.springframework.cloud.stream.annotation.Output;
+import org.springframework.cloud.stream.annotation.Source;
 import org.springframework.context.annotation.Bean;
 import org.springframework.integration.annotation.InboundChannelAdapter;
 import org.springframework.integration.annotation.Poller;
 import org.springframework.integration.core.MessageSource;
-import org.springframework.messaging.MessageChannel;
 import org.springframework.messaging.support.GenericMessage;
 
 import java.text.SimpleDateFormat;
@@ -35,18 +34,15 @@ import java.util.Date;
  * @author Glenn Renfro
  *
  */
-@EnableModule
+@EnableModule(Source.class)
 @EnableConfigurationProperties(TimeSourceOptionsMetadata.class)
 public class TimeSource {
 
 	@Autowired
 	private TimeSourceOptionsMetadata options;
 
-	@Output
-	public MessageChannel output;
-
 	@Bean
-	@InboundChannelAdapter(value = "output", autoStartup = "false", poller = @Poller(fixedDelay = "${fixedDelay}", maxMessagesPerPoll = "1"))
+	@InboundChannelAdapter(value = Source.OUTPUT, autoStartup = "false", poller = @Poller(fixedDelay = "${fixedDelay}", maxMessagesPerPoll = "1"))
 	public MessageSource<String> timerMessageSource() {
 		return () -> new GenericMessage<>(new SimpleDateFormat(this.options.getFormat()).format(new Date()));
 	}

spring-cloud-stream-samples/tap/src/main/java/config/TappingLoggingSink.java

@@ -18,25 +18,20 @@ package config;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
 import org.springframework.cloud.stream.annotation.EnableModule;
-import org.springframework.cloud.stream.annotation.Input;
+import org.springframework.cloud.stream.annotation.Sink;
 import org.springframework.integration.annotation.ServiceActivator;
-import org.springframework.messaging.MessageChannel;
 
 /**
  * @author Dave Syer
  * @author Marius Bogoevici
  */
-@EnableModule
+@EnableModule(Sink.class)
 public class TappingLoggingSink {
-	
+
 	private static Logger logger = LoggerFactory.getLogger(TappingLoggingSink.class);
 
-	@Input
-	public MessageChannel input;
-
-	@ServiceActivator(inputChannel="input")
+	@ServiceActivator(inputChannel = Sink.INPUT)
 	public void loggerSink(Object payload) {
 		logger.info("Received: " + payload);
 	}

spring-cloud-stream-samples/tap/src/main/java/demo/TapApplication.java

@@ -2,13 +2,11 @@ package demo;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
-import org.springframework.cloud.stream.annotation.EnableModule;
 import org.springframework.context.annotation.ComponentScan;
 
 import config.TappingLoggingSink;
 
 @SpringBootApplication
-@EnableModule
 @ComponentScan(basePackageClasses= TappingLoggingSink.class)
 public class TapApplication {
 

spring-cloud-stream-samples/transform/src/main/java/transform/LoggingTransformer.java

@@ -18,20 +18,16 @@ package transform;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.cloud.stream.annotation.EnableModule;
-import org.springframework.context.annotation.Bean;
+import org.springframework.cloud.stream.annotation.Processor;
 import org.springframework.integration.annotation.ServiceActivator;
-import org.springframework.integration.channel.DirectChannel;
-import org.springframework.messaging.MessageChannel;
-import org.springframework.messaging.SubscribableChannel;
 
 /**
  * @author Dave Syer
  *
  */
-@EnableModule
+@EnableModule(Processor.class)
 @ConfigurationProperties("module.logging")
 public class LoggingTransformer {
 
@@ -50,17 +46,7 @@ public class LoggingTransformer {
 		this.name = name;
 	}
 
-	@Bean
-	public MessageChannel input() {
-		return new DirectChannel();
-	}
-
-	@Bean
-	public SubscribableChannel output() {
-		return new DirectChannel();
-	}
-
-	@ServiceActivator(inputChannel = "input", outputChannel = "output")
+	@ServiceActivator(inputChannel = Processor.INPUT, outputChannel = Processor.OUTPUT)
 	public Object transform(Object payload) {
 		logger.info("Transformed by " + this.name + ": " + payload);
 		return payload;