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 218f5452ce26..740e54aa3418 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
@@ -1232,6 +1232,27 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          {{#hasHttpSignatureMethods}}
+          serializeToString(body, formParams, contentType, isBodyNullable),
+          {{/hasHttpSignatureMethods}}
+          {{^hasHttpSignatureMethods}}
+          null,
+          {{/hasHttpSignatureMethods}}
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1262,27 +1283,6 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          {{#hasHttpSignatureMethods}}
-          serializeToString(body, formParams, contentType, isBodyNullable),
-          {{/hasHttpSignatureMethods}}
-          {{^hasHttpSignatureMethods}}
-          null,
-          {{/hasHttpSignatureMethods}}
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1507,4 +1507,4 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/jersey3/ApiClient.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/jersey3/ApiClient.mustache
index 046a9f9bc8f6..afe437c1234f 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/jersey3/ApiClient.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/jersey3/ApiClient.mustache
@@ -1232,6 +1232,27 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          {{#hasHttpSignatureMethods}}
+          serializeToString(body, formParams, contentType, isBodyNullable),
+          {{/hasHttpSignatureMethods}}
+          {{^hasHttpSignatureMethods}}
+          null,
+          {{/hasHttpSignatureMethods}}
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1262,27 +1283,6 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          {{#hasHttpSignatureMethods}}
-          serializeToString(body, formParams, contentType, isBodyNullable),
-          {{/hasHttpSignatureMethods}}
-          {{^hasHttpSignatureMethods}}
-          null,
-          {{/hasHttpSignatureMethods}}
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1507,4 +1507,4 @@ public class ApiClient{{#jsr310}} extends JavaTimeFormatter{{/jsr310}} {
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
diff --git a/samples/client/others/java/jersey2-oneOf-Mixed/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/others/java/jersey2-oneOf-Mixed/src/main/java/org/openapitools/client/ApiClient.java
index b78da38971a9..6ebb7f070c63 100644
--- a/samples/client/others/java/jersey2-oneOf-Mixed/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/others/java/jersey2-oneOf-Mixed/src/main/java/org/openapitools/client/ApiClient.java
@@ -1011,6 +1011,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          null,
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1041,22 +1057,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          null,
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1263,4 +1263,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
diff --git a/samples/client/others/java/jersey2-oneOf-duplicates/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/others/java/jersey2-oneOf-duplicates/src/main/java/org/openapitools/client/ApiClient.java
index b78da38971a9..6ebb7f070c63 100644
--- a/samples/client/others/java/jersey2-oneOf-duplicates/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/others/java/jersey2-oneOf-duplicates/src/main/java/org/openapitools/client/ApiClient.java
@@ -1011,6 +1011,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          null,
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1041,22 +1057,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          null,
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1263,4 +1263,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
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 9a6871d98ff0..64046959492f 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
@@ -1152,6 +1152,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          null,
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1182,22 +1198,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          null,
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1420,4 +1420,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
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 9a6871d98ff0..64046959492f 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
@@ -1152,6 +1152,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          null,
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1182,22 +1198,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          null,
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1420,4 +1420,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
diff --git a/samples/client/petstore/java/jersey3-oneOf/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/jersey3-oneOf/src/main/java/org/openapitools/client/ApiClient.java
index 129418d9ed84..86beb14081d4 100644
--- a/samples/client/petstore/java/jersey3-oneOf/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/jersey3-oneOf/src/main/java/org/openapitools/client/ApiClient.java
@@ -1011,6 +1011,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          null,
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1041,22 +1057,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          null,
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1263,4 +1263,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
diff --git a/samples/client/petstore/java/jersey3/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/jersey3/src/main/java/org/openapitools/client/ApiClient.java
index c074a9aa162d..1b95a1248c77 100644
--- a/samples/client/petstore/java/jersey3/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/jersey3/src/main/java/org/openapitools/client/ApiClient.java
@@ -1234,6 +1234,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          serializeToString(body, formParams, contentType, isBodyNullable),
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1264,22 +1280,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          serializeToString(body, formParams, contentType, isBodyNullable),
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1502,4 +1502,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
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 20637170383c..a38d840e8e73 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
@@ -1060,6 +1060,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          null,
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1090,22 +1106,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          null,
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1312,4 +1312,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
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 ffa0c9c81fea..eac1f45038bd 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
@@ -1011,6 +1011,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          null,
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1041,22 +1057,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          null,
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1263,4 +1263,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
diff --git a/samples/openapi3/client/petstore/java/jersey2-java8-swagger1/src/main/java/org/openapitools/client/ApiClient.java b/samples/openapi3/client/petstore/java/jersey2-java8-swagger1/src/main/java/org/openapitools/client/ApiClient.java
index 3e873330d3ba..7367c4b933a6 100644
--- a/samples/openapi3/client/petstore/java/jersey2-java8-swagger1/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/openapi3/client/petstore/java/jersey2-java8-swagger1/src/main/java/org/openapitools/client/ApiClient.java
@@ -1136,6 +1136,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          null,
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1166,22 +1182,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          null,
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1404,4 +1404,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
diff --git a/samples/openapi3/client/petstore/java/jersey2-java8-swagger2/src/main/java/org/openapitools/client/ApiClient.java b/samples/openapi3/client/petstore/java/jersey2-java8-swagger2/src/main/java/org/openapitools/client/ApiClient.java
index 3e873330d3ba..7367c4b933a6 100644
--- a/samples/openapi3/client/petstore/java/jersey2-java8-swagger2/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/openapi3/client/petstore/java/jersey2-java8-swagger2/src/main/java/org/openapitools/client/ApiClient.java
@@ -1136,6 +1136,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          null,
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1166,22 +1182,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          null,
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1404,4 +1404,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file
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 0f84b73cba16..81fe9683c83e 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
@@ -1234,6 +1234,22 @@ public <T> ApiResponse<T> invokeAPI(
     // to support (constant) query string in `path`, e.g. "/posts?draft=1"
     WebTarget target = httpClient.target(targetURL);
 
+    // put all headers in one place
+    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
+    allHeaderParams.putAll(headerParams);
+
+    if (authNames != null) {
+      // update different parameters (e.g. headers) for authentication
+      updateParamsForAuth(
+          authNames,
+          queryParams,
+          allHeaderParams,
+          cookieParams,
+          serializeToString(body, formParams, contentType, isBodyNullable),
+          method,
+          target.getUri());
+    }
+
     if (queryParams != null) {
       for (Pair queryParam : queryParams) {
         if (queryParam.getValue() != null) {
@@ -1264,22 +1280,6 @@ public <T> ApiResponse<T> invokeAPI(
 
     Entity<?> entity = serialize(body, formParams, contentType, isBodyNullable);
 
-    // put all headers in one place
-    Map<String, String> allHeaderParams = new HashMap<>(defaultHeaderMap);
-    allHeaderParams.putAll(headerParams);
-
-    if (authNames != null) {
-      // update different parameters (e.g. headers) for authentication
-      updateParamsForAuth(
-          authNames,
-          queryParams,
-          allHeaderParams,
-          cookieParams,
-          serializeToString(body, formParams, contentType, isBodyNullable),
-          method,
-          target.getUri());
-    }
-
     for (Entry<String, String> entry : allHeaderParams.entrySet()) {
       String value = entry.getValue();
       if (value != null) {
@@ -1502,4 +1502,4 @@ protected void updateParamsForAuth(String[] authNames, List<Pair> queryParams, M
       auth.applyToParams(queryParams, headerParams, cookieParams, payload, method, uri);
     }
   }
-}
+}
\ No newline at end of file