[DOXIATOOLS-16] NullPointerException when site URL is being generated

git-svn-id: https://svn.apache.org/repos/asf/maven/doxia/doxia-tools/trunk@1388197 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/doxia-integration-tools/src/main/java/org/apache/maven/doxia/tools/DefaultSiteTool.java b/doxia-integration-tools/src/main/java/org/apache/maven/doxia/tools/DefaultSiteTool.java
index 300f377..1876524 100644
--- a/doxia-integration-tools/src/main/java/org/apache/maven/doxia/tools/DefaultSiteTool.java
+++ b/doxia-integration-tools/src/main/java/org/apache/maven/doxia/tools/DefaultSiteTool.java
@@ -1454,7 +1454,8 @@
     private static String getDistMgmntSiteUrl( Model model )
     {
         if ( model.getDistributionManagement() != null
-            && model.getDistributionManagement().getSite() != null )
+            && model.getDistributionManagement().getSite() != null
+            && model.getDistributionManagement().getSite().getUrl() != null )
         {
             return urlEncode( model.getDistributionManagement().getSite().getUrl() );
         }