JAL-2145 documentation of getWidth()

diff --git a/src/jalview/datamodel/AlignmentI.java b/src/jalview/datamodel/AlignmentI.java
index c15bb99..f1db4c0 100755 (executable)
--- a/src/jalview/datamodel/AlignmentI.java
+++ b/src/jalview/datamodel/AlignmentI.java
@@ -41,7 +41,8 @@ public interface AlignmentI extends AnnotatedCollectionI
    * 
    * Calculates the maximum width of the alignment, including gaps.
    * 
-   * @return Greatest sequence length within alignment.
+   * @return Greatest sequence length within alignment, or -1 if no sequences
+   *         present
    */
   @Override
   int getWidth();