INT-1848 Add order Attribute (mail)

spring-integration-mail/src/main/resources/org/springframework/integration/mail/config/spring-integration-mail-2.0.xsd

@@ -59,6 +59,14 @@
 				</xsd:annotation>
 			</xsd:attribute>
 			<xsd:attribute name="auto-startup" type="xsd:string" default="true"/>
+			<xsd:attribute name="order">
+				<xsd:annotation>
+					<xsd:documentation>
+						Specifies the order for invocation when this endpoint is connected as a
+						subscriber to a SubscribableChannel.
+					</xsd:documentation>
+				</xsd:annotation>
+			</xsd:attribute>
 		</xsd:complexType>
 	</xsd:element>
 

spring-integration-mail/src/test/java/org/springframework/integration/mail/config/MailOutboundChannelAdapterParserTests.java

@@ -45,6 +45,7 @@ public class MailOutboundChannelAdapterParserTests {
 		DirectFieldAccessor fieldAccessor = new DirectFieldAccessor(handler);
 		MailSender mailSender = (MailSender) fieldAccessor.getPropertyValue("mailSender");
 		assertNotNull(mailSender);
+		assertEquals(23, fieldAccessor.getPropertyValue("order"));
 	}
 
 	@Test

spring-integration-mail/src/test/java/org/springframework/integration/mail/config/mailOutboundChannelAdapterParserTests.xml

@@ -11,6 +11,7 @@
 			http://www.springframework.org/schema/integration/mail/spring-integration-mail.xsd">
 
 	<mail:outbound-channel-adapter id="adapterWithMailSenderReference"
+			order="23"
 			mail-sender="mailSender"/>
 
 	<mail:outbound-channel-adapter id="adapterWithHostProperty"