INT-3746: RemoteFileTemplate streaming backport

Resolves https://jira.spring.io/browse/INT-3746

spring-integration-file/src/main/java/org/springframework/integration/file/remote/RemoteFileTemplate.java

@@ -494,6 +494,10 @@ public class RemoteFileTemplate<F> implements RemoteFileOperations<F>, Initializ
 				}
 				dataInputStream = new ByteArrayInputStream(bytes);
 			}
+			else if (payload instanceof InputStream) {
+				dataInputStream = (InputStream) payload;
+				name = "InputStream payload";
+			}
 			else {
 				throw new IllegalArgumentException("Unsupported payload type. The only supported payloads are " +
 							"java.io.File, java.lang.String, and byte[]");

spring-integration-file/src/test/java/org/springframework/integration/file/remote/RemoteFileTemplateTests.java

@@ -23,7 +23,9 @@ import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
+import java.io.ByteArrayInputStream;
 import java.io.File;
+import java.io.IOException;
 import java.io.InputStream;
 
 import org.hamcrest.Matchers;
@@ -117,4 +119,12 @@ public class RemoteFileTemplateTests {
 		verify(this.session).write(Mockito.any(InputStream.class), Mockito.anyString());
 	}
 
+	@Test
+	public void testStream() throws IOException {
+		ByteArrayInputStream stream = new ByteArrayInputStream("foo".getBytes());
+		this.template.send(new GenericMessage<InputStream>(stream),
+				FileExistsMode.IGNORE);
+		verify(this.session).write(Mockito.eq(stream), Mockito.any());
+	}
+
 }