Ensures a JsonCreator annotated constructor is present if there are required fields, ensure the getters and setters are properly annotated for jaxrs-spec generator.

modules/openapi-generator/src/main/resources/JavaJaxRS/spec/pojo.mustache

@@ -34,9 +34,9 @@ public class {{classname}} {{#parent}}extends {{{.}}}{{/parent}} {{#vendorExtens
   {{/vendorExtensions.x-field-extra-annotation}}
   private {{#isContainer}}{{#useBeanValidation}}@Valid {{/useBeanValidation}}{{/isContainer}}{{{datatypeWithEnum}}} {{name}}{{#defaultValue}} = {{{.}}}{{/defaultValue}};
   {{/vars}}
+
   {{#generateBuilders}}
   {{^additionalProperties}}
-
   protected {{classname}}({{classname}}Builder<?, ?> b) {
     {{#parent}}
     super(b);
@@ -46,11 +46,33 @@ public class {{classname}} {{#parent}}extends {{{.}}}{{/parent}} {{#vendorExtens
     {{/vars}}
   }
 
-  public {{classname}}() {
-  }
   {{/additionalProperties}}
   {{/generateBuilders}}
+  public {{classname}}() {
+  }
+
+  {{#hasRequired}}
+  @JsonCreator
+  public {{classname}}(
+    {{#requiredVars}}
+    @JsonProperty(required = {{required}}, value = "{{baseName}}") {{>beanValidatedType}} {{name}}{{^-last}},{{/-last}}
+    {{/requiredVars}}
+  ) {
+    {{#parent}}
+    super(
+    {{#parentRequiredVars}}
+      {{name}}{{^-last}},{{/-last}}
+    {{/parentRequiredVars}}
+    );
+    {{/parent}}
+    {{#vars}}
+    {{#required}}
+    this.{{name}} = {{name}};
+    {{/required}}
+    {{/vars}}
+  }
 
+  {{/hasRequired}}
   {{#vars}}
   /**
    {{#description}}
@@ -71,12 +93,12 @@ public class {{classname}} {{#parent}}extends {{{.}}}{{/parent}} {{#vendorExtens
   {{#vendorExtensions.x-extra-annotation}}{{{vendorExtensions.x-extra-annotation}}}{{/vendorExtensions.x-extra-annotation}}{{#useSwaggerAnnotations}}
   @ApiModelProperty({{#example}}example = "{{{.}}}", {{/example}}{{#required}}required = {{required}}, {{/required}}value = "{{{description}}}"){{/useSwaggerAnnotations}}{{#useMicroProfileOpenAPIAnnotations}}
   @org.eclipse.microprofile.openapi.annotations.media.Schema({{#example}}example = "{{{.}}}", {{/example}}{{#required}}required = {{required}}, {{/required}}description = "{{{description}}}"){{/useMicroProfileOpenAPIAnnotations}}
-  @JsonProperty("{{baseName}}")
+  @JsonProperty({{#required}}required = {{required}}, value = {{/required}}"{{baseName}}")
   {{#useBeanValidation}}{{>beanValidation}}{{/useBeanValidation}}public {{>beanValidatedType}} {{getter}}() {
     return {{name}};
   }
 
-  @JsonProperty("{{baseName}}")
+  @JsonProperty({{#required}}required = {{required}}, value = {{/required}}"{{baseName}}")
   {{#vendorExtensions.x-setter-extra-annotation}}{{{vendorExtensions.x-setter-extra-annotation}}}
   {{/vendorExtensions.x-setter-extra-annotation}}public void {{setter}}({{{datatypeWithEnum}}} {{name}}) {
     this.{{name}} = {{name}};

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/AdditionalPropertiesAnyType.java

@@ -22,6 +22,9 @@
 public class AdditionalPropertiesAnyType extends HashMap<String, Object> implements Serializable {
   private String name;
 
+  public AdditionalPropertiesAnyType() {
+  }
+
   /**
    **/
   public AdditionalPropertiesAnyType name(String name) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/AdditionalPropertiesArray.java

@@ -23,6 +23,9 @@
 public class AdditionalPropertiesArray extends HashMap<String, List> implements Serializable {
   private String name;
 
+  public AdditionalPropertiesArray() {
+  }
+
   /**
    **/
   public AdditionalPropertiesArray name(String name) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/AdditionalPropertiesBoolean.java

@@ -22,6 +22,9 @@
 public class AdditionalPropertiesBoolean extends HashMap<String, Boolean> implements Serializable {
   private String name;
 
+  public AdditionalPropertiesBoolean() {
+  }
+
   /**
    **/
   public AdditionalPropertiesBoolean name(String name) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/AdditionalPropertiesClass.java

@@ -34,6 +34,9 @@ public class AdditionalPropertiesClass  implements Serializable {
   private Object anytype2;
   private Object anytype3;
 
+  public AdditionalPropertiesClass() {
+  }
+
   /**
    **/
   public AdditionalPropertiesClass mapString(Map<String, String> mapString) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/AdditionalPropertiesInteger.java

@@ -22,6 +22,9 @@
 public class AdditionalPropertiesInteger extends HashMap<String, Integer> implements Serializable {
   private String name;
 
+  public AdditionalPropertiesInteger() {
+  }
+
   /**
    **/
   public AdditionalPropertiesInteger name(String name) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/AdditionalPropertiesNumber.java

@@ -23,6 +23,9 @@
 public class AdditionalPropertiesNumber extends HashMap<String, BigDecimal> implements Serializable {
   private String name;
 
+  public AdditionalPropertiesNumber() {
+  }
+
   /**
    **/
   public AdditionalPropertiesNumber name(String name) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/AdditionalPropertiesObject.java

@@ -22,6 +22,9 @@
 public class AdditionalPropertiesObject extends HashMap<String, Map> implements Serializable {
   private String name;
 
+  public AdditionalPropertiesObject() {
+  }
+
   /**
    **/
   public AdditionalPropertiesObject name(String name) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/AdditionalPropertiesString.java

@@ -22,6 +22,9 @@
 public class AdditionalPropertiesString extends HashMap<String, String> implements Serializable {
   private String name;
 
+  public AdditionalPropertiesString() {
+  }
+
   /**
    **/
   public AdditionalPropertiesString name(String name) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/Animal.java

@@ -30,6 +30,16 @@ public class Animal  implements Serializable {
   private String className;
   private String color = "red";
 
+  public Animal() {
+  }
+
+  @JsonCreator
+  public Animal(
+    @JsonProperty(required = true, value = "className") String className
+  ) {
+    this.className = className;
+  }
+
   /**
    **/
   public Animal className(String className) {
@@ -39,12 +49,12 @@ public Animal className(String className) {
 
 
   @ApiModelProperty(required = true, value = "")
-  @JsonProperty("className")
+  @JsonProperty(required = true, value = "className")
   @NotNull public String getClassName() {
     return className;
   }
 
-  @JsonProperty("className")
+  @JsonProperty(required = true, value = "className")
   public void setClassName(String className) {
     this.className = className;
   }

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/ArrayOfArrayOfNumberOnly.java

@@ -24,6 +24,9 @@
 public class ArrayOfArrayOfNumberOnly  implements Serializable {
   private @Valid List<List<BigDecimal>> arrayArrayNumber = new ArrayList<>();
 
+  public ArrayOfArrayOfNumberOnly() {
+  }
+
   /**
    **/
   public ArrayOfArrayOfNumberOnly arrayArrayNumber(List<List<BigDecimal>> arrayArrayNumber) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/ArrayOfNumberOnly.java

@@ -24,6 +24,9 @@
 public class ArrayOfNumberOnly  implements Serializable {
   private @Valid List<BigDecimal> arrayNumber = new ArrayList<>();
 
+  public ArrayOfNumberOnly() {
+  }
+
   /**
    **/
   public ArrayOfNumberOnly arrayNumber(List<BigDecimal> arrayNumber) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/ArrayTest.java

@@ -26,6 +26,9 @@ public class ArrayTest  implements Serializable {
   private @Valid List<List<Long>> arrayArrayOfInteger = new ArrayList<>();
   private @Valid List<List<@Valid ReadOnlyFirst>> arrayArrayOfModel = new ArrayList<>();
 
+  public ArrayTest() {
+  }
+
   /**
    **/
   public ArrayTest arrayOfString(List<String> arrayOfString) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/BigCat.java

@@ -68,6 +68,18 @@ public static KindEnum fromValue(String value) {
 
   private KindEnum kind;
 
+  public BigCat() {
+  }
+
+  @JsonCreator
+  public BigCat(
+    @JsonProperty(required = true, value = "className") String className
+  ) {
+    super(
+      className
+    );
+  }
+
   /**
    **/
   public BigCat kind(KindEnum kind) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/Capitalization.java

@@ -25,6 +25,9 @@ public class Capitalization  implements Serializable {
   private String scAETHFlowPoints;
   private String ATT_NAME;
 
+  public Capitalization() {
+  }
+
   /**
    **/
   public Capitalization smallCamel(String smallCamel) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/Cat.java

@@ -21,6 +21,18 @@
 public class Cat extends Animal implements Serializable {
   private Boolean declawed;
 
+  public Cat() {
+  }
+
+  @JsonCreator
+  public Cat(
+    @JsonProperty(required = true, value = "className") String className
+  ) {
+    super(
+      className
+    );
+  }
+
   /**
    **/
   public Cat declawed(Boolean declawed) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/Category.java

@@ -21,6 +21,16 @@ public class Category  implements Serializable {
   private Long id;
   private String name = "default-name";
 
+  public Category() {
+  }
+
+  @JsonCreator
+  public Category(
+    @JsonProperty(required = true, value = "name") String name
+  ) {
+    this.name = name;
+  }
+
   /**
    **/
   public Category id(Long id) {
@@ -49,12 +59,12 @@ public Category name(String name) {
 
 
   @ApiModelProperty(required = true, value = "")
-  @JsonProperty("name")
+  @JsonProperty(required = true, value = "name")
   @NotNull public String getName() {
     return name;
   }
 
-  @JsonProperty("name")
+  @JsonProperty(required = true, value = "name")
   public void setName(String name) {
     this.name = name;
   }

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/ClassModel.java

@@ -22,6 +22,9 @@
 public class ClassModel  implements Serializable {
   private String propertyClass;
 
+  public ClassModel() {
+  }
+
   /**
    **/
   public ClassModel propertyClass(String propertyClass) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/Client.java

@@ -20,6 +20,9 @@
 public class Client  implements Serializable {
   private String client;
 
+  public Client() {
+  }
+
   /**
    **/
   public Client client(String client) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/Dog.java

@@ -21,6 +21,18 @@
 public class Dog extends Animal implements Serializable {
   private String breed;
 
+  public Dog() {
+  }
+
+  @JsonCreator
+  public Dog(
+    @JsonProperty(required = true, value = "className") String className
+  ) {
+    super(
+      className
+    );
+  }
+
   /**
    **/
   public Dog breed(String breed) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/EnumArrays.java

@@ -118,6 +118,9 @@ public static ArrayEnumEnum fromValue(String value) {
 
   private @Valid List<ArrayEnumEnum> arrayEnum = new ArrayList<>();
 
+  public EnumArrays() {
+  }
+
   /**
    **/
   public EnumArrays justSymbol(JustSymbolEnum justSymbol) {

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/EnumTest.java

@@ -214,6 +214,16 @@ public static EnumNumberEnum fromValue(Double value) {
   private EnumNumberEnum enumNumber;
   private OuterEnum outerEnum;
 
+  public EnumTest() {
+  }
+
+  @JsonCreator
+  public EnumTest(
+    @JsonProperty(required = true, value = "enum_string_required") EnumStringRequiredEnum enumStringRequired
+  ) {
+    this.enumStringRequired = enumStringRequired;
+  }
+
   /**
    **/
   public EnumTest enumString(EnumStringEnum enumString) {
@@ -242,12 +252,12 @@ public EnumTest enumStringRequired(EnumStringRequiredEnum enumStringRequired) {
 
 
   @ApiModelProperty(required = true, value = "")
-  @JsonProperty("enum_string_required")
+  @JsonProperty(required = true, value = "enum_string_required")
   @NotNull public EnumStringRequiredEnum getEnumStringRequired() {
     return enumStringRequired;
   }
 
-  @JsonProperty("enum_string_required")
+  @JsonProperty(required = true, value = "enum_string_required")
   public void setEnumStringRequired(EnumStringRequiredEnum enumStringRequired) {
     this.enumStringRequired = enumStringRequired;
   }

samples/server/petstore/jaxrs-spec-interface-response/src/gen/java/org/openapitools/model/FileSchemaTestClass.java

@@ -25,6 +25,9 @@ public class FileSchemaTestClass  implements Serializable {
   private ModelFile _file;
   private @Valid List<@Valid ModelFile> files = new ArrayList<>();
 
+  public FileSchemaTestClass() {
+  }
+
   /**
    **/
   public FileSchemaTestClass _file(ModelFile _file) {