Add check for list size before attempting to set last element field value. (#557)

Author: jason-cohen

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SpringCodegen.java

@@ -576,7 +576,9 @@ private void removeHeadersFromAllParams(List<CodegenParameter> allParams) {
                 allParams.add(p);
             }
         }
-        allParams.get(allParams.size()-1).hasMore =false;
+        if (!allParams.isEmpty()) {
+            allParams.get(allParams.size()-1).hasMore =false;
+        }
     }
 
     @Override