1 files changed, 7 insertions, 0 deletions
diff --git a/src/main/java/at/gv/egiz/pdfas/impl/api/CheckHelper.java b/src/main/java/at/gv/egiz/pdfas/impl/api/CheckHelper.java
index 0c2d7ca..dcded42 100644
--- a/src/main/java/at/gv/egiz/pdfas/impl/api/CheckHelper.java
+++ b/src/main/java/at/gv/egiz/pdfas/impl/api/CheckHelper.java
@@ -68,6 +68,7 @@ public final class CheckHelper
       checkSignaturePositioning(sp.getSignaturePositioning());
     }
     checkSignatureKeyIdentifier(sp.getSignatureKeyIdentifier(), sp.getSignatureDevice());
+    checkTimestampHandler(sp);
   }
 
   /**
@@ -148,6 +149,12 @@ public final class CheckHelper
       throw new IllegalArgumentException("The signatureType must be one of the Constants.SIGNATURE_TYPE_* constants. " + signatureType);
     }
   }
+  
+  protected static void checkTimestampHandler(SignParameters params) {
+     if (params.getTimeStamperImpl() != null && !Constants.SIGNATURE_TYPE_BINARY.equals(params.getSignatureType())) {
+        throw new IllegalArgumentException("timestamping is only allowed for binary signatures ");
+     }
+  }
 
   protected static void checkProfileId(String profileId)
   {