Merge pull request #268 from beccagaspard/npe-fix

Fix for NPE when Thread.currentThread().getContextClassLoader() is null.

Author: parrt

contributors.txt

@@ -67,3 +67,4 @@ YYYY/MM/DD, github id, Full name, email
 2020/07/23, dyuan0226, David Yuan, dyuan1@andrew.cmu.edu
 2020/09/06, peteruhnak, Peter Uhnak, i.uhnak@gmail.com
 2020/09/16, Dvoreth, Jarmila Emanuela Panwitz, jaremapan@gmail.com
+2020/10/01, beccagaspard, Becca Gaspard, beccagaspard at gmail dot com

src/org/stringtemplate/v4/STGroup.java

@@ -837,12 +837,12 @@ public ST createStringTemplateInternally(ST proto) {
     public URL getRootDirURL() { return null; }
 
     public URL getURL(String fileName) {
-        URL url;
+        URL url = null;
         ClassLoader cl = Thread.currentThread().getContextClassLoader();
-        url = cl.getResource(fileName);
+        if ( cl!=null ) url = cl.getResource(fileName);
         if ( url==null ) {
             cl = this.getClass().getClassLoader();
-            url = cl.getResource(fileName);
+            if ( cl!=null ) url = cl.getResource(fileName);
         }
         return url;
     }