Prevent build failing when .git is missing

libbuild/GitRevMavenTask/src/GitRevMavenTask.java

@@ -42,6 +42,9 @@ public class GitRevMavenTask extends AbstractMojo {
     private String buildNumberPropertyName = "releaseNr";
     @Parameter
     private String commitDatePropertyName = "DSTAMP";
+    
+    /** Default revision number when no commit can be found */
+    private static final String DEFAULT_REV_NUMBER = "0000";
 
     Log log = this.getLog();
 
@@ -93,20 +96,26 @@ public class GitRevMavenTask extends AbstractMojo {
             }
             walk.dispose();
             if (lastTag == null) {
-                revision = "0000";
+                revision = DEFAULT_REV_NUMBER;
             } else {
                 revision = Integer.toString(distance + 9000);
             }
         } catch (final IOException e) {
-            e.printStackTrace();
+        	revision = DEFAULT_REV_NUMBER;
+        } catch(IllegalArgumentException e) {
+        	revision = DEFAULT_REV_NUMBER;
         }
         if (project != null) {
-            project.getProperties().put(this.branchPropertyName, branch);
-            log.info("GitrevMavenTask: set property " + this.branchPropertyName + "='" + branch + "'");            
+        	if(branch != null) {
+        		project.getProperties().put(this.branchPropertyName, branch);
+        		log.info("GitrevMavenTask: set property " + this.branchPropertyName + "='" + branch + "'");
+        	}
             project.getProperties().put(this.buildNumberPropertyName, revision);
             log.info("GitrevMavenTask: set property " + this.buildNumberPropertyName + "=" + revision);
-            project.getProperties().put(this.commitDatePropertyName, commitDate);
-            log.info("GitrevMavenTask: set property " + this.commitDatePropertyName + "=" + commitDate);
+            if(commitDate != null) {
+            	project.getProperties().put(this.commitDatePropertyName, commitDate);
+            	log.info("GitrevMavenTask: set property " + this.commitDatePropertyName + "=" + commitDate);
+            }
         } else {
             log.error("GitrevMavenTask: no Maven project");
             System.out.println(this.branchPropertyName + "=" + branch);