1 files changed, 20 insertions, 8 deletions
diff --git a/src/net/sourceforge/plantuml/sequencediagram/MessageExoType.java b/src/net/sourceforge/plantuml/sequencediagram/MessageExoType.java
index 261f803..49aef40 100644
--- a/src/net/sourceforge/plantuml/sequencediagram/MessageExoType.java
+++ b/src/net/sourceforge/plantuml/sequencediagram/MessageExoType.java
@@ -2,7 +2,7 @@
  * PlantUML : a free UML diagram generator
  * ========================================================================
  *
- * (C) Copyright 2009-2017, Arnaud Roques
+ * (C) Copyright 2009-2020, Arnaud Roques
  *
  * Project Info:  http://plantuml.com
  * 
@@ -39,16 +39,14 @@ public enum MessageExoType {
 	FROM_LEFT, TO_LEFT, FROM_RIGHT, TO_RIGHT;
 
 	public int getDirection() {
-		if (this == MessageExoType.FROM_LEFT) {
+		switch (this) {
+		case FROM_LEFT:
 			return 1;
-		}
-		if (this == MessageExoType.TO_LEFT) {
+		case TO_LEFT:
 			return -1;
-		}
-		if (this == MessageExoType.TO_RIGHT) {
+		case TO_RIGHT:
 			return 1;
-		}
-		if (this == MessageExoType.FROM_RIGHT) {
+		case FROM_RIGHT:
 			return -1;
 		}
 		throw new IllegalStateException();
@@ -62,4 +60,18 @@ public enum MessageExoType {
 		return this == MessageExoType.FROM_RIGHT || this == MessageExoType.TO_RIGHT;
 	}
 
+	public MessageExoType reverse() {
+		switch (this) {
+		case FROM_LEFT:
+			return TO_LEFT;
+		case TO_RIGHT:
+			return FROM_RIGHT;
+		case FROM_RIGHT:
+			return TO_RIGHT;
+		case TO_LEFT:
+			return FROM_LEFT;
+		}
+		throw new IllegalStateException();
+	}
+
 }