Update sample-parent-context following changes to integration starter

See gh-5528

spring-boot-samples/spring-boot-sample-parent-context/src/main/java/sample/parent/SampleParentContextApplication.java

@@ -16,20 +16,71 @@
 
 package sample.parent;
 
+import java.io.File;
+
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.boot.builder.SpringApplicationBuilder;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
-import org.springframework.context.annotation.ImportResource;
+import org.springframework.context.annotation.Bean;
+import org.springframework.integration.channel.DirectChannel;
+import org.springframework.integration.dsl.IntegrationFlow;
+import org.springframework.integration.dsl.IntegrationFlows;
+import org.springframework.integration.dsl.SourcePollingChannelAdapterSpec;
+import org.springframework.integration.dsl.core.Pollers;
+import org.springframework.integration.dsl.support.Consumer;
+import org.springframework.integration.file.FileReadingMessageSource;
+import org.springframework.integration.file.FileWritingMessageHandler;
 
 @SpringBootApplication
 @EnableConfigurationProperties(ServiceProperties.class)
 public class SampleParentContextApplication {
 
 	@EnableAutoConfiguration
-	@ImportResource("integration-context.xml")
 	protected static class Parent {
 
+		@Bean
+		public FileReadingMessageSource fileReader() {
+			FileReadingMessageSource reader = new FileReadingMessageSource();
+			reader.setDirectory(new File("target/input"));
+			return reader;
+		}
+
+		@Bean
+		public DirectChannel inputChannel() {
+			return new DirectChannel();
+		}
+
+		@Bean
+		public DirectChannel outputChannel() {
+			return new DirectChannel();
+		}
+
+		@Bean
+		public FileWritingMessageHandler fileWriter() {
+			FileWritingMessageHandler writer = new FileWritingMessageHandler(
+					new File("target/output"));
+			writer.setExpectReply(false);
+			return writer;
+		}
+
+		@Bean
+		public IntegrationFlow integrationFlow(SampleEndpoint endpoint) {
+			return IntegrationFlows.from(fileReader(), new FixedRatePoller())
+					.channel(inputChannel()).handle(endpoint).channel(outputChannel())
+					.handle(fileWriter()).get();
+		}
+
+		private static class FixedRatePoller
+				implements Consumer<SourcePollingChannelAdapterSpec> {
+
+			@Override
+			public void accept(SourcePollingChannelAdapterSpec spec) {
+				spec.poller(Pollers.fixedRate(500));
+			}
+
+		}
+
 	}
 
 	public static void main(String[] args) throws Exception {