[Java] Fix SubClass annotations missing from the base class

modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenModel.java

@@ -17,6 +17,7 @@ public class CodegenModel {
     // References to parent and interface CodegenModels. Only set when code generator supports inheritance.
     public CodegenModel parentModel;
     public List<CodegenModel> interfaceModels;
+    public List<CodegenModel> children;
 
     public String name, classname, title, description, classVarName, modelJson, dataType;
     public String classFilename; // store the class file name, mainly used for import

modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java

@@ -180,6 +180,18 @@ public Map<String, Object> postProcessAllModels(Map<String, Object> objs) {
                     }
                 }
             }
+            // Let parent know about all its children
+            for (String name : allModels.keySet()) {
+                CodegenModel cm = allModels.get(name);
+                CodegenModel parent = allModels.get(cm.parent);
+                while (parent != null) {
+                    if (parent.children == null) {
+                        parent.children = new ArrayList<CodegenModel>();
+                    }
+                    parent.children.add(cm);
+                    parent = allModels.get(parent.parent);
+                }
+            }
         }
         return objs;
     }

modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/AbstractJavaCodegen.java

@@ -253,6 +253,8 @@ public void processOpts() {
         importMapping.put("ApiModelProperty", "io.swagger.annotations.ApiModelProperty");
         importMapping.put("ApiModel", "io.swagger.annotations.ApiModel");
         importMapping.put("JsonProperty", "com.fasterxml.jackson.annotation.JsonProperty");
+        importMapping.put("JsonSubTypes", "com.fasterxml.jackson.annotation.JsonSubTypes");
+        importMapping.put("JsonTypeInfo", "com.fasterxml.jackson.annotation.JsonTypeInfo");
         importMapping.put("JsonCreator", "com.fasterxml.jackson.annotation.JsonCreator");
         importMapping.put("JsonValue", "com.fasterxml.jackson.annotation.JsonValue");
         importMapping.put("SerializedName", "com.google.gson.annotations.SerializedName");
@@ -628,6 +630,10 @@ public CodegenModel fromModel(String name, Model model, Map<String, Model> allDe
         if(codegenModel.description != null) {
             codegenModel.imports.add("ApiModel");
         }
+        if (codegenModel.discriminator != null && additionalProperties.containsKey("jackson")) {
+            codegenModel.imports.add("JsonSubTypes");
+            codegenModel.imports.add("JsonTypeInfo");
+        }
         if (allDefinitions != null && codegenModel.parentSchema != null && codegenModel.hasEnums) {
             final Model parentModel = allDefinitions.get(codegenModel.parentSchema);
             final CodegenModel parentCodegenModel = super.fromModel(codegenModel.parent, parentModel);

modules/swagger-codegen/src/main/resources/Java/pojo.mustache

@@ -2,7 +2,7 @@
  * {{#description}}{{.}}{{/description}}{{^description}}{{classname}}{{/description}}
  */{{#description}}
 @ApiModel(description = "{{{description}}}"){{/description}}
-{{>generatedAnnotation}}
+{{>generatedAnnotation}}{{#discriminator}}{{>typeInfoAnnotation}}{{/discriminator}}
 public class {{classname}} {{#parent}}extends {{{parent}}} {{/parent}}{{#parcelableModel}}implements Parcelable {{#serializableModel}}, Serializable {{/serializableModel}}{{/parcelableModel}}{{^parcelableModel}}{{#serializableModel}}implements Serializable {{/serializableModel}}{{/parcelableModel}}{
   {{#vars}}
     {{#isEnum}}

modules/swagger-codegen/src/main/resources/Java/typeInfoAnnotation.mustache

@@ -0,0 +1,5 @@
+{{#jackson}}
+@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "{{discriminator}}" )
+@JsonSubTypes({ 
+  {{#children}}@JsonSubTypes.Type(value = {{name}}.class, name = "{{name}}"),{{/children}}
+}){{/jackson}}

samples/client/petstore/java/feign/src/main/java/io/swagger/client/model/Animal.java

@@ -16,13 +16,18 @@
 import java.util.Objects;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonSubTypes;
+import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
 /**
  * Animal
  */
-
+@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "className" )
+@JsonSubTypes({ 
+  @JsonSubTypes.Type(value = Dog.class, name = "Dog"),@JsonSubTypes.Type(value = Cat.class, name = "Cat"),
+})
 public class Animal {
   @JsonProperty("className")
   private String className = null;

samples/client/petstore/java/jersey1/src/main/java/io/swagger/client/model/Animal.java

@@ -16,13 +16,18 @@
 import java.util.Objects;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonSubTypes;
+import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
 /**
  * Animal
  */
-
+@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "className" )
+@JsonSubTypes({ 
+  @JsonSubTypes.Type(value = Dog.class, name = "Dog"),@JsonSubTypes.Type(value = Cat.class, name = "Cat"),
+})
 public class Animal {
   @JsonProperty("className")
   private String className = null;

samples/client/petstore/java/jersey2-java8/src/main/java/io/swagger/client/RFC3339DateFormat.java

@@ -0,0 +1,32 @@
+/*
+ * Swagger Petstore
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * OpenAPI spec version: 1.0.0
+ * Contact: [email protected]
+ *
+ * NOTE: This class is auto generated by the swagger code generator program.
+ * https://github.com/swagger-api/swagger-codegen.git
+ * Do not edit the class manually.
+ */
+
+package io.swagger.client;
+
+import com.fasterxml.jackson.databind.util.ISO8601DateFormat;
+import com.fasterxml.jackson.databind.util.ISO8601Utils;
+
+import java.text.FieldPosition;
+import java.util.Date;
+
+
+public class RFC3339DateFormat extends ISO8601DateFormat {
+
+  // Same as ISO8601DateFormat but serializing milliseconds.
+  @Override
+  public StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition) {
+    String value = ISO8601Utils.format(date, true);
+    toAppendTo.append(value);
+    return toAppendTo;
+  }
+
+}

samples/client/petstore/java/jersey2-java8/src/main/java/io/swagger/client/model/Animal.java

@@ -16,13 +16,18 @@
 import java.util.Objects;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonSubTypes;
+import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
 /**
  * Animal
  */
-
+@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "className" )
+@JsonSubTypes({ 
+  @JsonSubTypes.Type(value = Dog.class, name = "Dog"),@JsonSubTypes.Type(value = Cat.class, name = "Cat"),
+})
 public class Animal {
   @JsonProperty("className")
   private String className = null;

samples/client/petstore/java/jersey2/src/main/java/io/swagger/client/model/Animal.java

@@ -16,13 +16,18 @@
 import java.util.Objects;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonSubTypes;
+import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
 /**
  * Animal
  */
-
+@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "className" )
+@JsonSubTypes({ 
+  @JsonSubTypes.Type(value = Dog.class, name = "Dog"),@JsonSubTypes.Type(value = Cat.class, name = "Cat"),
+})
 public class Animal {
   @JsonProperty("className")
   private String className = null;