Using Optional.ofNullable() at the fluent setters to prevent NPE (#20406)

* * Uses Optional.ofNullable() at the fluent setters to prevent NPE
* Fixes issue #17538

* updates samples

Author: slobodator

modules/openapi-generator/src/main/resources/JavaSpring/pojo.mustache

@@ -156,7 +156,7 @@ public class {{classname}}{{#parent}} extends {{{parent}}}{{/parent}}{{^parent}}
   {{! begin feature: fluent setter methods }}
   public {{classname}} {{name}}({{{datatypeWithEnum}}} {{name}}) {
     {{#openApiNullable}}
-    this.{{name}} = {{#isNullable}}JsonNullable.of({{/isNullable}}{{#useOptional}}{{^required}}{{^isNullable}}{{^isContainer}}Optional.of({{/isContainer}}{{/isNullable}}{{/required}}{{/useOptional}}{{name}}{{#isNullable}}){{/isNullable}}{{#useOptional}}{{^required}}{{^isNullable}}{{^isContainer}}){{/isContainer}}{{/isNullable}}{{/required}}{{/useOptional}};
+    this.{{name}} = {{#isNullable}}JsonNullable.of({{/isNullable}}{{#useOptional}}{{^required}}{{^isNullable}}{{^isContainer}}Optional.ofNullable({{/isContainer}}{{/isNullable}}{{/required}}{{/useOptional}}{{name}}{{#isNullable}}){{/isNullable}}{{#useOptional}}{{^required}}{{^isNullable}}{{^isContainer}}){{/isContainer}}{{/isNullable}}{{/required}}{{/useOptional}};
     {{/openApiNullable}}
     {{^openApiNullable}}
     this.{{name}} = {{name}};

modules/openapi-generator/src/test/java/org/openapitools/codegen/java/spring/SpringCodegenTest.java

@@ -228,7 +228,7 @@ public void doAnnotateDatesOnModelParametersWithOptionalAndJsonNullable() throws
                 .containsWithNameAndAttributes("DateTimeFormat", ImmutableMap.of("iso", "DateTimeFormat.ISO.DATE_TIME"))
                 .toProperty().toType()
                 .assertMethod("born", "LocalDate")
-                .bodyContainsLines("this.born = Optional.of(born)")
+                .bodyContainsLines("this.born = Optional.ofNullable(born)")
                 .doesNotHaveComment();
     }
 
@@ -4397,9 +4397,10 @@ private void assertJsonNullableMethod(JavaFileAssert javaFileAssert, String type
 
     private void assertWrapperMethod(JavaFileAssert javaFileAssert, String wrapperType, String type, String expectedName, String getterReturnType){
         String methodName = StringUtils.capitalize(expectedName);
+        var of = wrapperType.equals("Optional") ? "ofNullable" : "of";
         javaFileAssert.assertMethod(expectedName)
                 .hasReturnType("Animal")
-                .bodyContainsLines("this."+expectedName+" = "+wrapperType+".of("+expectedName+");", "return this;")
+                .bodyContainsLines("this." + expectedName + " = "+wrapperType+ "." + of + "(" +expectedName+");", "return this;")
                 .assertParameter(expectedName)
                 .hasType(type)
                 .toMethod()

samples/openapi3/client/petstore/spring-cloud-3-with-optional/src/main/java/org/openapitools/model/Category.java

@@ -26,7 +26,7 @@ public class Category {
   private Optional<@Pattern(regexp = "^[a-zA-Z0-9]+[a-zA-Z0-9\\.\\-_]*[a-zA-Z0-9]+$") String> name = Optional.empty();
 
   public Category id(Long id) {
-    this.id = Optional.of(id);
+    this.id = Optional.ofNullable(id);
     return this;
   }
 
@@ -45,7 +45,7 @@ public void setId(Optional<Long> id) {
   }
 
   public Category name(String name) {
-    this.name = Optional.of(name);
+    this.name = Optional.ofNullable(name);
     return this;
   }
 

samples/openapi3/client/petstore/spring-cloud-3-with-optional/src/main/java/org/openapitools/model/ModelApiResponse.java

@@ -30,7 +30,7 @@ public class ModelApiResponse {
   private Optional<String> message = Optional.empty();
 
   public ModelApiResponse code(Integer code) {
-    this.code = Optional.of(code);
+    this.code = Optional.ofNullable(code);
     return this;
   }
 
@@ -49,7 +49,7 @@ public void setCode(Optional<Integer> code) {
   }
 
   public ModelApiResponse type(String type) {
-    this.type = Optional.of(type);
+    this.type = Optional.ofNullable(type);
     return this;
   }
 
@@ -68,7 +68,7 @@ public void setType(Optional<String> type) {
   }
 
   public ModelApiResponse message(String message) {
-    this.message = Optional.of(message);
+    this.message = Optional.ofNullable(message);
     return this;
   }
 

samples/openapi3/client/petstore/spring-cloud-3-with-optional/src/main/java/org/openapitools/model/Order.java

@@ -75,7 +75,7 @@ public static StatusEnum fromValue(String value) {
   private Optional<Boolean> complete = Optional.of(false);
 
   public Order id(Long id) {
-    this.id = Optional.of(id);
+    this.id = Optional.ofNullable(id);
     return this;
   }
 
@@ -94,7 +94,7 @@ public void setId(Optional<Long> id) {
   }
 
   public Order petId(Long petId) {
-    this.petId = Optional.of(petId);
+    this.petId = Optional.ofNullable(petId);
     return this;
   }
 
@@ -113,7 +113,7 @@ public void setPetId(Optional<Long> petId) {
   }
 
   public Order quantity(Integer quantity) {
-    this.quantity = Optional.of(quantity);
+    this.quantity = Optional.ofNullable(quantity);
     return this;
   }
 
@@ -132,7 +132,7 @@ public void setQuantity(Optional<Integer> quantity) {
   }
 
   public Order shipDate(OffsetDateTime shipDate) {
-    this.shipDate = Optional.of(shipDate);
+    this.shipDate = Optional.ofNullable(shipDate);
     return this;
   }
 
@@ -151,7 +151,7 @@ public void setShipDate(Optional<OffsetDateTime> shipDate) {
   }
 
   public Order status(StatusEnum status) {
-    this.status = Optional.of(status);
+    this.status = Optional.ofNullable(status);
     return this;
   }
 
@@ -170,7 +170,7 @@ public void setStatus(Optional<StatusEnum> status) {
   }
 
   public Order complete(Boolean complete) {
-    this.complete = Optional.of(complete);
+    this.complete = Optional.ofNullable(complete);
     return this;
   }
 

samples/openapi3/client/petstore/spring-cloud-3-with-optional/src/main/java/org/openapitools/model/Pet.java

@@ -92,7 +92,7 @@ public Pet(String name, List<String> photoUrls) {
   }
 
   public Pet id(Long id) {
-    this.id = Optional.of(id);
+    this.id = Optional.ofNullable(id);
     return this;
   }
 
@@ -111,7 +111,7 @@ public void setId(Optional<Long> id) {
   }
 
   public Pet category(Category category) {
-    this.category = Optional.of(category);
+    this.category = Optional.ofNullable(category);
     return this;
   }
 
@@ -203,7 +203,7 @@ public void setTags(List<@Valid Tag> tags) {
   }
 
   public Pet status(StatusEnum status) {
-    this.status = Optional.of(status);
+    this.status = Optional.ofNullable(status);
     return this;
   }
 

samples/openapi3/client/petstore/spring-cloud-3-with-optional/src/main/java/org/openapitools/model/Tag.java

@@ -26,7 +26,7 @@ public class Tag {
   private Optional<String> name = Optional.empty();
 
   public Tag id(Long id) {
-    this.id = Optional.of(id);
+    this.id = Optional.ofNullable(id);
     return this;
   }
 
@@ -45,7 +45,7 @@ public void setId(Optional<Long> id) {
   }
 
   public Tag name(String name) {
-    this.name = Optional.of(name);
+    this.name = Optional.ofNullable(name);
     return this;
   }
 

samples/openapi3/client/petstore/spring-cloud-3-with-optional/src/main/java/org/openapitools/model/User.java

@@ -38,7 +38,7 @@ public class User {
   private Optional<Integer> userStatus = Optional.empty();
 
   public User id(Long id) {
-    this.id = Optional.of(id);
+    this.id = Optional.ofNullable(id);
     return this;
   }
 
@@ -57,7 +57,7 @@ public void setId(Optional<Long> id) {
   }
 
   public User username(String username) {
-    this.username = Optional.of(username);
+    this.username = Optional.ofNullable(username);
     return this;
   }
 
@@ -76,7 +76,7 @@ public void setUsername(Optional<String> username) {
   }
 
   public User firstName(String firstName) {
-    this.firstName = Optional.of(firstName);
+    this.firstName = Optional.ofNullable(firstName);
     return this;
   }
 
@@ -95,7 +95,7 @@ public void setFirstName(Optional<String> firstName) {
   }
 
   public User lastName(String lastName) {
-    this.lastName = Optional.of(lastName);
+    this.lastName = Optional.ofNullable(lastName);
     return this;
   }
 
@@ -114,7 +114,7 @@ public void setLastName(Optional<String> lastName) {
   }
 
   public User email(String email) {
-    this.email = Optional.of(email);
+    this.email = Optional.ofNullable(email);
     return this;
   }
 
@@ -133,7 +133,7 @@ public void setEmail(Optional<String> email) {
   }
 
   public User password(String password) {
-    this.password = Optional.of(password);
+    this.password = Optional.ofNullable(password);
     return this;
   }
 
@@ -152,7 +152,7 @@ public void setPassword(Optional<String> password) {
   }
 
   public User phone(String phone) {
-    this.phone = Optional.of(phone);
+    this.phone = Optional.ofNullable(phone);
     return this;
   }
 
@@ -171,7 +171,7 @@ public void setPhone(Optional<String> phone) {
   }
 
   public User userStatus(Integer userStatus) {
-    this.userStatus = Optional.of(userStatus);
+    this.userStatus = Optional.ofNullable(userStatus);
     return this;
   }
 

samples/server/petstore/springboot-useoptional/src/main/java/org/openapitools/model/AdditionalPropertiesAnyType.java

@@ -30,7 +30,7 @@ public class AdditionalPropertiesAnyType {
   private Optional<String> name = Optional.empty();
 
   public AdditionalPropertiesAnyType name(String name) {
-    this.name = Optional.of(name);
+    this.name = Optional.ofNullable(name);
     return this;
   }
 

samples/server/petstore/springboot-useoptional/src/main/java/org/openapitools/model/AdditionalPropertiesArray.java

@@ -31,7 +31,7 @@ public class AdditionalPropertiesArray {
   private Optional<String> name = Optional.empty();
 
   public AdditionalPropertiesArray name(String name) {
-    this.name = Optional.of(name);
+    this.name = Optional.ofNullable(name);
     return this;
   }