JAL-1312 more helpful error message when translation breaks

diff --git a/src/jalview/gui/AlignFrame.java b/src/jalview/gui/AlignFrame.java
index 77c3b6a..ceb08ee 100755 (executable)
--- a/src/jalview/gui/AlignFrame.java
+++ b/src/jalview/gui/AlignFrame.java
@@ -4603,7 +4603,13 @@ public class AlignFrame extends GAlignFrame implements DropTargetListener,
     } catch (Exception ex)
     {
       al = null;
-      jalview.bin.Cache.log.debug("Exception during translation.", ex);
+      jalview.bin.Cache.log.error("Exception during translation. Please report this !", ex);
+      JOptionPane
+      .showMessageDialog(
+              Desktop.desktop,
+              "Unfortunately, something went wrong when translating your sequences.\nPlease take a look in the Jalview java console\nand submit a bug report including the stacktrace.",
+              "Implementation error: Translation Failed", JOptionPane.ERROR_MESSAGE);
+      return;
     }
     if (al == null)
     {