diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/jersey2/ApiClient.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/jersey2/ApiClient.mustache
index e76f84bdff49..bb78ec3a458a 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/jersey2/ApiClient.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/jersey2/ApiClient.mustache
@@ -526,7 +526,7 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
    * @return API client
    */
   public ApiClient setUserAgent(String userAgent) {
-    userAgent = userAgent;
+    this.userAgent = userAgent;
     addDefaultHeader("User-Agent", userAgent);
     return this;
   }
diff --git a/modules/openapi-generator/src/test/resources/2_0/templates/Java/libraries/jersey2/ApiClient.mustache b/modules/openapi-generator/src/test/resources/2_0/templates/Java/libraries/jersey2/ApiClient.mustache
index f8a121d1aded..a1c91c8eadf9 100644
--- a/modules/openapi-generator/src/test/resources/2_0/templates/Java/libraries/jersey2/ApiClient.mustache
+++ b/modules/openapi-generator/src/test/resources/2_0/templates/Java/libraries/jersey2/ApiClient.mustache
@@ -526,7 +526,7 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
    * @return API client
    */
   public ApiClient setUserAgent(String userAgent) {
-    userAgent = userAgent;
+    this.userAgent = userAgent;
     addDefaultHeader("User-Agent", userAgent);
     return this;
   }
diff --git a/samples/client/petstore/java/jersey2-java8-localdatetime/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/jersey2-java8-localdatetime/src/main/java/org/openapitools/client/ApiClient.java
index 43d4978c6eef..9b3aa790f3df 100644
--- a/samples/client/petstore/java/jersey2-java8-localdatetime/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/jersey2-java8-localdatetime/src/main/java/org/openapitools/client/ApiClient.java
@@ -442,7 +442,7 @@ public ApiClient setOauthScope(String scope) {
    * @return API client
    */
   public ApiClient setUserAgent(String userAgent) {
-    userAgent = userAgent;
+    this.userAgent = userAgent;
     addDefaultHeader("User-Agent", userAgent);
     return this;
   }
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
index 43d4978c6eef..9b3aa790f3df 100644
--- a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
@@ -442,7 +442,7 @@ public ApiClient setOauthScope(String scope) {
    * @return API client
    */
   public ApiClient setUserAgent(String userAgent) {
-    userAgent = userAgent;
+    this.userAgent = userAgent;
     addDefaultHeader("User-Agent", userAgent);
     return this;
   }
diff --git a/samples/openapi3/client/extensions/x-auth-id-alias/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java b/samples/openapi3/client/extensions/x-auth-id-alias/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
index 6609b1d0db81..7c0a3e1ab68c 100644
--- a/samples/openapi3/client/extensions/x-auth-id-alias/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/openapi3/client/extensions/x-auth-id-alias/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
@@ -378,7 +378,7 @@ public ApiClient setBearerToken(String bearerToken) {
    * @return API client
    */
   public ApiClient setUserAgent(String userAgent) {
-    userAgent = userAgent;
+    this.userAgent = userAgent;
     addDefaultHeader("User-Agent", userAgent);
     return this;
   }
diff --git a/samples/openapi3/client/petstore/java/jersey2-java8-special-characters/src/main/java/org/openapitools/client/ApiClient.java b/samples/openapi3/client/petstore/java/jersey2-java8-special-characters/src/main/java/org/openapitools/client/ApiClient.java
index 2ed169966eea..727093b74f34 100644
--- a/samples/openapi3/client/petstore/java/jersey2-java8-special-characters/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/openapi3/client/petstore/java/jersey2-java8-special-characters/src/main/java/org/openapitools/client/ApiClient.java
@@ -323,7 +323,7 @@ public ApiClient setBearerToken(String bearerToken) {
    * @return API client
    */
   public ApiClient setUserAgent(String userAgent) {
-    userAgent = userAgent;
+    this.userAgent = userAgent;
     addDefaultHeader("User-Agent", userAgent);
     return this;
   }
diff --git a/samples/openapi3/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java b/samples/openapi3/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
index dec198d485cf..2d889cc99d86 100644
--- a/samples/openapi3/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/openapi3/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiClient.java
@@ -526,7 +526,7 @@ public ApiClient setOauthScope(String scope) {
    * @return API client
    */
   public ApiClient setUserAgent(String userAgent) {
-    userAgent = userAgent;
+    this.userAgent = userAgent;
     addDefaultHeader("User-Agent", userAgent);
     return this;
   }