Merge pull request #160 from johnjaylward/FixXMLNPE

Fixes possible NullPointerException in XML.toString(object, tagName)

Author: stleary

XML.java

@@ -1,7 +1,7 @@
 package org.json;
 
 /*
-Copyright (c) 2002 JSON.org
+Copyright (c) 2015 JSON.org
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -30,7 +30,7 @@ of this software and associated documentation files (the "Software"), to deal
  * This provides static methods to convert an XML text into a JSONObject,
  * and to covert a JSONObject into an XML text.
  * @author JSON.org
- * @version 2014-05-03
+ * @version 2015-10-14
  */
 public class XML {
 
@@ -468,23 +468,25 @@ public static String toString(Object object, String tagName)
 // XML does not have good support for arrays. If an array appears in a place
 // where XML is lacking, synthesize an <array> element.
 
-        } else {
+        }
+        if(object!=null){
             if (object.getClass().isArray()) {
                 object = new JSONArray(object);
             }
+            
             if (object instanceof JSONArray) {
                 ja = (JSONArray)object;
                 length = ja.length();
                 for (i = 0; i < length; i += 1) {
                     sb.append(toString(ja.opt(i), tagName == null ? "array" : tagName));
                 }
                 return sb.toString();
-            } else {
-                string = (object == null) ? "null" : escape(object.toString());
-                return (tagName == null) ? "\"" + string + "\"" :
-                    (string.length() == 0) ? "<" + tagName + "/>" :
-                    "<" + tagName + ">" + string + "</" + tagName + ">";
             }
         }
+        string = (object == null) ? "null" : escape(object.toString());
+        return (tagName == null) ? "\"" + string + "\"" :
+            (string.length() == 0) ? "<" + tagName + "/>" :
+            "<" + tagName + ">" + string + "</" + tagName + ">";
+            
     }
 }