diff --git a/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultGenerator.java b/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultGenerator.java
index 5f11f99d99c..228be1a3ef5 100644
--- a/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultGenerator.java
+++ b/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultGenerator.java
@@ -526,6 +526,7 @@ public class DefaultGenerator extends AbstractGenerator implements Generator {
                         if (in != null) {
                             LOGGER.info("writing file " + outputFile);
                             IOUtils.copy(in, out);
+                            out.close();
                         } else {
                             LOGGER.error("can't open " + templateFile + " for input");
                         }