Modified exiftool display method to only continue if a valid EXIF datastream was found.

plugins/Exiftool.inc

@@ -33,29 +33,30 @@ class Exiftool {
   function displayMetadata() { 
     $output='';
     $exifDom = DOMDocument::loadXML($this->item->get_datastream_dissemination('EXIF'));
-    
-    $description = $exifDom->getElementsByTagNameNS('http://www.w3.org/1999/02/22-rdf-syntax-ns#','Description');
-    if ($description->length > 0) { 
-      $description=$description->item(0);
-      $output .= '<div class="fedora_technical_metadata"><ul>';
-      for ($i=0;$i<$description->childNodes->length;$i++){ 
-	$name=$description->childNodes->item($i)->nodeName;
-	$value=$description->childNodes->item($i)->nodeValue;
-	if ($name != '#text'  && !preg_match('/^System\:.*$/',$name) && trim($value) != '') { 
-	  list($type,$name) = preg_split('/\:/',$name);
-	  $name = trim(preg_replace('/(?<!^)([A-Z][a-z]|(?<=[a-z])[A-Z])/'," $1", $name));
-	  $output .= '<li><b>'.$name. '</b>:  '. $value .' </li>';
+    if ($exifDom != NULL) {
+      $description = $exifDom->getElementsByTagNameNS('http://www.w3.org/1999/02/22-rdf-syntax-ns#','Description');
+      if ($description->length > 0) { 
+	$description=$description->item(0);
+	$output .= '<div class="fedora_technical_metadata"><ul>';
+	for ($i=0;$i<$description->childNodes->length;$i++){ 
+	  $name=$description->childNodes->item($i)->nodeName;
+	  $value=$description->childNodes->item($i)->nodeValue;
+	  if ($name != '#text'  && !preg_match('/^System\:.*$/',$name) && trim($value) != '') { 
+	    list($type,$name) = preg_split('/\:/',$name);
+	    $name = trim(preg_replace('/(?<!^)([A-Z][a-z]|(?<=[a-z])[A-Z])/'," $1", $name));
+	    $output .= '<li><b>'.$name. '</b>:  '. $value .' </li>';
+	  }
 	}
+	$output.='</ul></div>';
+	
+	$fieldset = array(
+	  '#title' => t("!text", array('!text' => 'Technical Metadata')),
+	  '#collapsible' => TRUE,
+	  '#collapsed' => TRUE,
+	  '#value' => $output
+	);
+	$output  = theme('fieldset', $fieldset);
       }
-      $output.='</ul></div>';
-      
-      $fieldset = array(
-	'#title' => t("!text", array('!text' => 'Technical Metadata')),
-	'#collapsible' => TRUE,
-	'#collapsed' => TRUE,
-	'#value' => $output
-      );
-      $output  = theme('fieldset', $fieldset);
     }
     return $output;
   }