Avoid 'null' entries in exported packages.

- Occurred when a dependency jar did not have the ExportPackages
  manifest header.

1 files changed, 3 insertions, 1 deletions

diff --git a/jdisc_core/src/main/java/com/yahoo/jdisc/core/ExportPackages.java b/jdisc_core/src/main/java/com/yahoo/jdisc/core/ExportPackages.java
index dda33c2d1a8..3a706101790 100644
--- a/jdisc_core/src/main/java/com/yahoo/jdisc/core/ExportPackages.java
+++ b/jdisc_core/src/main/java/com/yahoo/jdisc/core/ExportPackages.java
@@ -58,7 +58,9 @@ public class ExportPackages {
            .append("org.aopalliance.aop");
 
         for (int i = 1; i < jars.length; ++i) {
-            out.append(", ").append(getExportedPackages(jars[i]));
+            String exports = getExportedPackages(jars[i]);
+            if (exports != null && ! exports.isEmpty())
+                out.append(", ").append(exports);
         }
         return out.toString();
     }