update java generators to respect default value

Author: wing328

modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java

@@ -336,6 +336,7 @@ apiTemplateFiles are for API outputs only (controllers/handlers).
 
     @Setter @Getter boolean arrayDefaultToEmpty, arrayNullableDefaultToEmpty, arrayOptionalNullableDefaultToEmpty, arrayOptionalDefaultToEmpty;
     @Setter @Getter boolean mapDefaultToEmpty, mapNullableDefaultToEmpty, mapOptionalNullableDefaultToEmpty, mapOptionalDefaultToEmpty;
+    @Setter @Getter protected boolean defaultToEmptyContainer;
     final String DEFAULT_TO_EMPTY_CONTAINER = "defaultToEmptyContainer";
     final List EMPTY_LIST = new ArrayList();
 
@@ -4235,7 +4236,7 @@ public CodegenProperty fromProperty(String name, Schema p, boolean required, boo
         }
 
         // override defaultValue if it's not set and defaultToEmptyContainer is set
-        if (p.getDefault() == null && additionalProperties.containsKey("defaultToEmptyContainer")) {
+        if (p.getDefault() == null && defaultToEmptyContainer) {
             updateDefaultToEmptyContainer(property, p);
         }
 
@@ -4328,6 +4329,8 @@ void parseDefaultToEmptyContainer(String input) {
                     LOGGER.error("Skipped invalid container type `{}` in the rule `{}`.", containerType, input);
                 }
             }
+
+            defaultToEmptyContainer = true;
         }
 
     }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractJavaCodegen.java

@@ -1306,7 +1306,10 @@ public String toArrayDefaultValue(CodegenProperty cp, Schema schema) {
     public String toDefaultValue(CodegenProperty cp, Schema schema) {
         schema = ModelUtils.getReferencedSchema(this.openAPI, schema);
         if (ModelUtils.isArraySchema(schema)) {
-            if (schema.getDefault() == null) {
+            if (defaultToEmptyContainer) {
+                // if default to empty container option is set, respect the default values provided in the spec
+                return toArrayDefaultValue(cp, schema);
+            } else if (schema.getDefault() == null) {
                 // nullable or containerDefaultToNull set to true
                 if (cp.isNullable || containerDefaultToNull) {
                     return null;
@@ -1323,6 +1326,16 @@ public String toDefaultValue(CodegenProperty cp, Schema schema) {
                 return null;
             }
 
+            if (defaultToEmptyContainer) {
+                // respect the default values provided in the spec when the option is enabled
+                if (schema.getDefault() != null) {
+                    return String.format(Locale.ROOT, "new %s<>()",
+                            instantiationTypes().getOrDefault("map", "HashMap"));
+                } else {
+                    return null;
+                }
+            }
+
             // nullable or containerDefaultToNull set to true
             if (cp.isNullable || containerDefaultToNull) {
                 return null;

samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/model/AllOfModelArrayAnyOfAllOfLinkListColumn1.java

@@ -56,7 +56,7 @@ public class AllOfModelArrayAnyOfAllOfLinkListColumn1 {
   public static final String SERIALIZED_NAME_VALUE = "value";
   @SerializedName(SERIALIZED_NAME_VALUE)
   @javax.annotation.Nonnull
-  private List<AllOfModelArrayAnyOfAllOfLinkListColumn1Value> value = new ArrayList<>();
+  private List<AllOfModelArrayAnyOfAllOfLinkListColumn1Value> value;
 
   public AllOfModelArrayAnyOfAllOfLinkListColumn1() {
   }

samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/model/NewPet.java

@@ -88,7 +88,7 @@ public class NewPet {
   public static final String SERIALIZED_NAME_PHOTO_URLS = "photoUrls";
   @SerializedName(SERIALIZED_NAME_PHOTO_URLS)
   @javax.annotation.Nonnull
-  private List<String> photoUrls = new ArrayList<>();
+  private List<String> photoUrls;
 
   public static final String SERIALIZED_NAME_TAGS = "tags";
   @SerializedName(SERIALIZED_NAME_TAGS)

samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/model/Pet.java

@@ -72,7 +72,7 @@ public class Pet {
   public static final String SERIALIZED_NAME_PHOTO_URLS = "photoUrls";
   @SerializedName(SERIALIZED_NAME_PHOTO_URLS)
   @javax.annotation.Nonnull
-  private List<String> photoUrls = new ArrayList<>();
+  private List<String> photoUrls;
 
   public static final String SERIALIZED_NAME_TAGS = "tags";
   @SerializedName(SERIALIZED_NAME_TAGS)

samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/model/PetComposition.java

@@ -72,7 +72,7 @@ public class PetComposition {
   public static final String SERIALIZED_NAME_PHOTO_URLS = "photoUrls";
   @SerializedName(SERIALIZED_NAME_PHOTO_URLS)
   @javax.annotation.Nonnull
-  private List<String> photoUrls = new ArrayList<>();
+  private List<String> photoUrls;
 
   public static final String SERIALIZED_NAME_TAGS = "tags";
   @SerializedName(SERIALIZED_NAME_TAGS)

samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/model/PetRef.java

@@ -72,7 +72,7 @@ public class PetRef {
   public static final String SERIALIZED_NAME_PHOTO_URLS = "photoUrls";
   @SerializedName(SERIALIZED_NAME_PHOTO_URLS)
   @javax.annotation.Nonnull
-  private List<String> photoUrls = new ArrayList<>();
+  private List<String> photoUrls;
 
   public static final String SERIALIZED_NAME_TAGS = "tags";
   @SerializedName(SERIALIZED_NAME_TAGS)

samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/model/PetUsingAllOf.java

@@ -72,7 +72,7 @@ public class PetUsingAllOf {
   public static final String SERIALIZED_NAME_PHOTO_URLS = "photoUrls";
   @SerializedName(SERIALIZED_NAME_PHOTO_URLS)
   @javax.annotation.Nonnull
-  private List<String> photoUrls = new ArrayList<>();
+  private List<String> photoUrls;
 
   public static final String SERIALIZED_NAME_TAGS = "tags";
   @SerializedName(SERIALIZED_NAME_TAGS)

samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/model/PetWithRequiredTags.java

@@ -72,12 +72,12 @@ public class PetWithRequiredTags {
   public static final String SERIALIZED_NAME_PHOTO_URLS = "photoUrls";
   @SerializedName(SERIALIZED_NAME_PHOTO_URLS)
   @javax.annotation.Nonnull
-  private List<String> photoUrls = new ArrayList<>();
+  private List<String> photoUrls;
 
   public static final String SERIALIZED_NAME_TAGS = "tags";
   @SerializedName(SERIALIZED_NAME_TAGS)
   @javax.annotation.Nonnull
-  private List<Tag> tags = new ArrayList<>();
+  private List<Tag> tags;
 
   /**
    * pet status in the store