diff --git a/modules/openapi-generator/src/main/resources/Java/apiException.mustache b/modules/openapi-generator/src/main/resources/Java/apiException.mustache
index 31d2a807e2a7..894486729ec7 100644
--- a/modules/openapi-generator/src/main/resources/Java/apiException.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/apiException.mustache
@@ -7,6 +7,8 @@ import java.util.List;
 
 {{>generatedAnnotation}}
 public class ApiException extends{{#useRuntimeException}} RuntimeException {{/useRuntimeException}}{{^useRuntimeException}} Exception {{/useRuntimeException}}{
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/jersey2/apiException.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/jersey2/apiException.mustache
index 74a419aacf16..d10322379483 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/jersey2/apiException.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/jersey2/apiException.mustache
@@ -14,6 +14,8 @@ import java.util.TreeMap;
  */
 {{>generatedAnnotation}}
 public class ApiException extends{{#useRuntimeException}} RuntimeException {{/useRuntimeException}}{{^useRuntimeException}} Exception {{/useRuntimeException}}{
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/jersey3/apiException.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/jersey3/apiException.mustache
index 74a419aacf16..d10322379483 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/jersey3/apiException.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/jersey3/apiException.mustache
@@ -14,6 +14,8 @@ import java.util.TreeMap;
  */
 {{>generatedAnnotation}}
 public class ApiException extends{{#useRuntimeException}} RuntimeException {{/useRuntimeException}}{{^useRuntimeException}} Exception {{/useRuntimeException}}{
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/native/JSON.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/native/JSON.mustache
index 19eea0bcf4c4..5f53904810fd 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/native/JSON.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/native/JSON.mustache
@@ -27,9 +27,9 @@ public class JSON {
   public JSON() {
     mapper = JsonMapper.builder()
         .serializationInclusion(JsonInclude.Include.NON_NULL)
-        .configure(MapperFeature.ALLOW_COERCION_OF_SCALARS, false)
-        .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, true)
-        .configure(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE, true)
+        .disable(MapperFeature.ALLOW_COERCION_OF_SCALARS)
+        .enable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES)
+        .enable(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE)
         .disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
         .enable(SerializationFeature.WRITE_ENUMS_USING_TO_STRING)
         .enable(DeserializationFeature.READ_ENUMS_USING_TO_STRING)
diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/native/apiException.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/native/apiException.mustache
index 3d0eee4bf9c6..9596b73b6db6 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/native/apiException.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/native/apiException.mustache
@@ -6,6 +6,8 @@ import java.net.http.HttpHeaders;
 
 {{>generatedAnnotation}}
 public class ApiException extends{{#useRuntimeException}} RuntimeException {{/useRuntimeException}}{{^useRuntimeException}} Exception {{/useRuntimeException}}{
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private HttpHeaders responseHeaders = null;
     private String responseBody = null;
diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/apiException.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/apiException.mustache
index ed5be359c3a6..3cd6edaf718e 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/apiException.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/apiException.mustache
@@ -16,6 +16,8 @@ import java.util.TreeMap;
 @SuppressWarnings("serial")
 {{>generatedAnnotation}}
 public class ApiException extends{{#useRuntimeException}} RuntimeException {{/useRuntimeException}}{{^useRuntimeException}} Exception {{/useRuntimeException}}{
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/vertx/apiException.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/vertx/apiException.mustache
index 6e9bbdbb88df..9ce81015615a 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/vertx/apiException.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/vertx/apiException.mustache
@@ -8,6 +8,8 @@ import io.vertx.core.MultiMap;
 
 {{>generatedAnnotation}}
 public class ApiException extends{{#useRuntimeException}} RuntimeException {{/useRuntimeException}}{{^useRuntimeException}} Exception {{/useRuntimeException}}{
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private MultiMap responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/echo_api/java/apache-httpclient/src/main/java/org/openapitools/client/ApiException.java b/samples/client/echo_api/java/apache-httpclient/src/main/java/org/openapitools/client/ApiException.java
index 53d011b4ce5c..756539af8776 100644
--- a/samples/client/echo_api/java/apache-httpclient/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/echo_api/java/apache-httpclient/src/main/java/org/openapitools/client/ApiException.java
@@ -18,6 +18,8 @@
 
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/ApiException.java b/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/ApiException.java
index 6e3850c5d71d..e9e08a6b83e1 100644
--- a/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/ApiException.java
@@ -17,6 +17,8 @@
 
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private HttpHeaders responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/JSON.java b/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/JSON.java
index 5c966f6fa4a9..cbc1ebd5fa91 100644
--- a/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/JSON.java
+++ b/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/JSON.java
@@ -20,9 +20,9 @@ public class JSON {
   public JSON() {
     mapper = JsonMapper.builder()
         .serializationInclusion(JsonInclude.Include.NON_NULL)
-        .configure(MapperFeature.ALLOW_COERCION_OF_SCALARS, false)
-        .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, true)
-        .configure(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE, true)
+        .disable(MapperFeature.ALLOW_COERCION_OF_SCALARS)
+        .enable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES)
+        .enable(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE)
         .disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
         .enable(SerializationFeature.WRITE_ENUMS_USING_TO_STRING)
         .enable(DeserializationFeature.READ_ENUMS_USING_TO_STRING)
diff --git a/samples/client/echo_api/java/okhttp-gson/src/main/java/org/openapitools/client/ApiException.java b/samples/client/echo_api/java/okhttp-gson/src/main/java/org/openapitools/client/ApiException.java
index 678ff6a2839b..add48b225c5d 100644
--- a/samples/client/echo_api/java/okhttp-gson/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/echo_api/java/okhttp-gson/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/echo_api/java/resteasy/src/main/java/org/openapitools/client/ApiException.java b/samples/client/echo_api/java/resteasy/src/main/java/org/openapitools/client/ApiException.java
index 53d011b4ce5c..756539af8776 100644
--- a/samples/client/echo_api/java/resteasy/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/echo_api/java/resteasy/src/main/java/org/openapitools/client/ApiException.java
@@ -18,6 +18,8 @@
 
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/others/java/okhttp-gson-oneOf/src/main/java/org/openapitools/client/ApiException.java b/samples/client/others/java/okhttp-gson-oneOf/src/main/java/org/openapitools/client/ApiException.java
index d2969de6563c..28d6ba6585a7 100644
--- a/samples/client/others/java/okhttp-gson-oneOf/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/others/java/okhttp-gson-oneOf/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/others/java/okhttp-gson-streaming/src/main/java/org/openapitools/client/ApiException.java b/samples/client/others/java/okhttp-gson-streaming/src/main/java/org/openapitools/client/ApiException.java
index bc44cc38c7e8..d24e3cd58347 100644
--- a/samples/client/others/java/okhttp-gson-streaming/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/others/java/okhttp-gson-streaming/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/apache-httpclient/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/apache-httpclient/src/main/java/org/openapitools/client/ApiException.java
index 942dacc1d303..fb88f1c7a2fe 100644
--- a/samples/client/petstore/java/apache-httpclient/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/apache-httpclient/src/main/java/org/openapitools/client/ApiException.java
@@ -18,6 +18,8 @@
 
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/jersey2-java8-localdatetime/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/jersey2-java8-localdatetime/src/main/java/org/openapitools/client/ApiException.java
index 1c98dfd2a4b1..229b85d62c46 100644
--- a/samples/client/petstore/java/jersey2-java8-localdatetime/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/jersey2-java8-localdatetime/src/main/java/org/openapitools/client/ApiException.java
@@ -21,6 +21,8 @@
  */
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
index 1c98dfd2a4b1..229b85d62c46 100644
--- a/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
@@ -21,6 +21,8 @@
  */
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/jersey3/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/jersey3/src/main/java/org/openapitools/client/ApiException.java
index cf61335328e5..dd9e52ba9aea 100644
--- a/samples/client/petstore/java/jersey3/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/jersey3/src/main/java/org/openapitools/client/ApiException.java
@@ -21,6 +21,8 @@
  */
 @jakarta.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/native-async/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/native-async/src/main/java/org/openapitools/client/ApiException.java
index 068ba4081360..e743d68b91be 100644
--- a/samples/client/petstore/java/native-async/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/native-async/src/main/java/org/openapitools/client/ApiException.java
@@ -17,6 +17,8 @@
 
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private HttpHeaders responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/native-async/src/main/java/org/openapitools/client/JSON.java b/samples/client/petstore/java/native-async/src/main/java/org/openapitools/client/JSON.java
index 5c966f6fa4a9..cbc1ebd5fa91 100644
--- a/samples/client/petstore/java/native-async/src/main/java/org/openapitools/client/JSON.java
+++ b/samples/client/petstore/java/native-async/src/main/java/org/openapitools/client/JSON.java
@@ -20,9 +20,9 @@ public class JSON {
   public JSON() {
     mapper = JsonMapper.builder()
         .serializationInclusion(JsonInclude.Include.NON_NULL)
-        .configure(MapperFeature.ALLOW_COERCION_OF_SCALARS, false)
-        .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, true)
-        .configure(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE, true)
+        .disable(MapperFeature.ALLOW_COERCION_OF_SCALARS)
+        .enable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES)
+        .enable(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE)
         .disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
         .enable(SerializationFeature.WRITE_ENUMS_USING_TO_STRING)
         .enable(DeserializationFeature.READ_ENUMS_USING_TO_STRING)
diff --git a/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/ApiException.java
index 94037ce979a4..f0f00ac39062 100644
--- a/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/ApiException.java
@@ -17,6 +17,8 @@
 
 @jakarta.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private HttpHeaders responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/JSON.java b/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/JSON.java
index b929796031f8..e9f45fbafa95 100644
--- a/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/JSON.java
+++ b/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/JSON.java
@@ -20,9 +20,9 @@ public class JSON {
   public JSON() {
     mapper = JsonMapper.builder()
         .serializationInclusion(JsonInclude.Include.NON_NULL)
-        .configure(MapperFeature.ALLOW_COERCION_OF_SCALARS, false)
-        .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, true)
-        .configure(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE, true)
+        .disable(MapperFeature.ALLOW_COERCION_OF_SCALARS)
+        .enable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES)
+        .enable(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE)
         .disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
         .enable(SerializationFeature.WRITE_ENUMS_USING_TO_STRING)
         .enable(DeserializationFeature.READ_ENUMS_USING_TO_STRING)
diff --git a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/ApiException.java
index 068ba4081360..e743d68b91be 100644
--- a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/ApiException.java
@@ -17,6 +17,8 @@
 
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private HttpHeaders responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/JSON.java b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/JSON.java
index 5c966f6fa4a9..cbc1ebd5fa91 100644
--- a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/JSON.java
+++ b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/JSON.java
@@ -20,9 +20,9 @@ public class JSON {
   public JSON() {
     mapper = JsonMapper.builder()
         .serializationInclusion(JsonInclude.Include.NON_NULL)
-        .configure(MapperFeature.ALLOW_COERCION_OF_SCALARS, false)
-        .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, true)
-        .configure(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE, true)
+        .disable(MapperFeature.ALLOW_COERCION_OF_SCALARS)
+        .enable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES)
+        .enable(DeserializationFeature.FAIL_ON_INVALID_SUBTYPE)
         .disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
         .enable(SerializationFeature.WRITE_ENUMS_USING_TO_STRING)
         .enable(DeserializationFeature.READ_ENUMS_USING_TO_STRING)
diff --git a/samples/client/petstore/java/okhttp-gson-3.1/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/okhttp-gson-3.1/src/main/java/org/openapitools/client/ApiException.java
index c4e3814b18d0..4acf930b015e 100644
--- a/samples/client/petstore/java/okhttp-gson-3.1/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/okhttp-gson-3.1/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/okhttp-gson-awsv4signature/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/okhttp-gson-awsv4signature/src/main/java/org/openapitools/client/ApiException.java
index c4e3814b18d0..4acf930b015e 100644
--- a/samples/client/petstore/java/okhttp-gson-awsv4signature/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/okhttp-gson-awsv4signature/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/okhttp-gson-dynamicOperations/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/okhttp-gson-dynamicOperations/src/main/java/org/openapitools/client/ApiException.java
index 17cf7621b8f2..d6197326dc6c 100644
--- a/samples/client/petstore/java/okhttp-gson-dynamicOperations/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/okhttp-gson-dynamicOperations/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/okhttp-gson-group-parameter/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/okhttp-gson-group-parameter/src/main/java/org/openapitools/client/ApiException.java
index c4e3814b18d0..4acf930b015e 100644
--- a/samples/client/petstore/java/okhttp-gson-group-parameter/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/okhttp-gson-group-parameter/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/okhttp-gson-nullable-required/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/okhttp-gson-nullable-required/src/main/java/org/openapitools/client/ApiException.java
index c4e3814b18d0..4acf930b015e 100644
--- a/samples/client/petstore/java/okhttp-gson-nullable-required/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/okhttp-gson-nullable-required/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/org/openapitools/client/ApiException.java
index 17cf7621b8f2..d6197326dc6c 100644
--- a/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/okhttp-gson-swagger1/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/okhttp-gson-swagger1/src/main/java/org/openapitools/client/ApiException.java
index c4e3814b18d0..4acf930b015e 100644
--- a/samples/client/petstore/java/okhttp-gson-swagger1/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/okhttp-gson-swagger1/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/okhttp-gson-swagger2/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/okhttp-gson-swagger2/src/main/java/org/openapitools/client/ApiException.java
index c4e3814b18d0..4acf930b015e 100644
--- a/samples/client/petstore/java/okhttp-gson-swagger2/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/okhttp-gson-swagger2/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/ApiException.java
index 17cf7621b8f2..d6197326dc6c 100644
--- a/samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/ApiException.java
@@ -23,6 +23,8 @@
 @SuppressWarnings("serial")
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/resteasy/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/resteasy/src/main/java/org/openapitools/client/ApiException.java
index 942dacc1d303..fb88f1c7a2fe 100644
--- a/samples/client/petstore/java/resteasy/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/resteasy/src/main/java/org/openapitools/client/ApiException.java
@@ -18,6 +18,8 @@
 
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/vertx-no-nullable/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/vertx-no-nullable/src/main/java/org/openapitools/client/ApiException.java
index f37d7e3764cd..fae827ae1cf7 100644
--- a/samples/client/petstore/java/vertx-no-nullable/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/vertx-no-nullable/src/main/java/org/openapitools/client/ApiException.java
@@ -19,6 +19,8 @@
 
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private MultiMap responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/client/petstore/java/vertx/src/main/java/org/openapitools/client/ApiException.java b/samples/client/petstore/java/vertx/src/main/java/org/openapitools/client/ApiException.java
index f37d7e3764cd..fae827ae1cf7 100644
--- a/samples/client/petstore/java/vertx/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/client/petstore/java/vertx/src/main/java/org/openapitools/client/ApiException.java
@@ -19,6 +19,8 @@
 
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private MultiMap responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/openapi3/client/extensions/x-auth-id-alias/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java b/samples/openapi3/client/extensions/x-auth-id-alias/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
index efc394e679d5..b2f8c388e035 100644
--- a/samples/openapi3/client/extensions/x-auth-id-alias/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/openapi3/client/extensions/x-auth-id-alias/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
@@ -21,6 +21,8 @@
  */
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/openapi3/client/petstore/java/jersey2-java8-special-characters/src/main/java/org/openapitools/client/ApiException.java b/samples/openapi3/client/petstore/java/jersey2-java8-special-characters/src/main/java/org/openapitools/client/ApiException.java
index b7060042a5d8..8e2053f5a2d9 100644
--- a/samples/openapi3/client/petstore/java/jersey2-java8-special-characters/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/openapi3/client/petstore/java/jersey2-java8-special-characters/src/main/java/org/openapitools/client/ApiException.java
@@ -21,6 +21,8 @@
  */
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/openapi3/client/petstore/java/jersey2-java8-swagger1/src/main/java/org/openapitools/client/ApiException.java b/samples/openapi3/client/petstore/java/jersey2-java8-swagger1/src/main/java/org/openapitools/client/ApiException.java
index 8bf05ab9b33d..2bb85d841d64 100644
--- a/samples/openapi3/client/petstore/java/jersey2-java8-swagger1/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/openapi3/client/petstore/java/jersey2-java8-swagger1/src/main/java/org/openapitools/client/ApiException.java
@@ -21,6 +21,8 @@
  */
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/openapi3/client/petstore/java/jersey2-java8-swagger2/src/main/java/org/openapitools/client/ApiException.java b/samples/openapi3/client/petstore/java/jersey2-java8-swagger2/src/main/java/org/openapitools/client/ApiException.java
index 8bf05ab9b33d..2bb85d841d64 100644
--- a/samples/openapi3/client/petstore/java/jersey2-java8-swagger2/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/openapi3/client/petstore/java/jersey2-java8-swagger2/src/main/java/org/openapitools/client/ApiException.java
@@ -21,6 +21,8 @@
  */
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;
diff --git a/samples/openapi3/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java b/samples/openapi3/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
index 1c98dfd2a4b1..229b85d62c46 100644
--- a/samples/openapi3/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
+++ b/samples/openapi3/client/petstore/java/jersey2-java8/src/main/java/org/openapitools/client/ApiException.java
@@ -21,6 +21,8 @@
  */
 @javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen")
 public class ApiException extends Exception {
+    private static final long serialVersionUID = 1L;
+
     private int code = 0;
     private Map<String, List<String>> responseHeaders = null;
     private String responseBody = null;