fix NPE

.gitignore

@@ -9,5 +9,5 @@
 /.project
 /.gradle
 /build
-/out
+out
 *~

build.gradle

@@ -71,6 +71,10 @@ test {
     }
 }
 
+clean {
+    delete 'out'
+}
+
 asciidoctor {
     attributes toc: 'left',
             doctype: 'book',

src/main/java/org/xbib/netty/http/client/Client.java

@@ -104,7 +104,7 @@ public final class Client {
         this.http2ResponseHandler = new Http2ResponseHandler();
         this.transports = new CopyOnWriteArrayList<>();
         List<HttpAddress> nodes = clientConfig.getNodes();
-        if (!nodes.isEmpty()) {
+        if (nodes != null && !nodes.isEmpty()) {
             Integer limit = clientConfig.getNodeConnectionLimit();
             if (limit == null || limit > nodes.size()) {
                 limit = nodes.size();