Attach cause to RuntimeException when available. Otherwise, the original exception can be swallowed which makes error forensics more difficult.

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@819205 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 15 insertions, 1 deletions

diff --git a/src/java/org/apache/fop/events/EventExceptionManager.java b/src/java/org/apache/fop/events/EventExceptionManager.java
index f6a115450..1072600c9 100644
--- a/src/java/org/apache/fop/events/EventExceptionManager.java
+++ b/src/java/org/apache/fop/events/EventExceptionManager.java
@@ -58,7 +58,21 @@ public class EventExceptionManager {
             }
         } else {
             String msg = EventFormatter.format(event);
-            throw new RuntimeException(msg);
+            //Get original exception as cause if it is given as one of the parameters
+            Throwable t = null;
+            Iterator iter = event.getParams().values().iterator();
+            while (iter.hasNext()) {
+                Object o = iter.next();
+                if (o instanceof Throwable) {
+                    t = (Throwable)o;
+                    break;
+                }
+            }
+            if (t != null) {
+                throw new RuntimeException(msg, t);
+            } else {
+                throw new RuntimeException(msg);
+            }
         }
     }