diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavaUndertowServerCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavaUndertowServerCodegen.java
new file mode 100644
index 00000000000..bde091e68e3
--- /dev/null
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavaUndertowServerCodegen.java
@@ -0,0 +1,184 @@
+package org.openapitools.codegen.languages;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+import org.openapitools.codegen.*;
+import org.openapitools.codegen.languages.features.BeanValidationFeatures;
+import org.openapitools.codegen.languages.features.UseGenericResponseFeatures;
+import org.openapitools.codegen.utils.URLPathUtil;
+import io.swagger.v3.oas.models.*;
+import io.swagger.v3.core.util.Json;
+
+import org.apache.commons.lang3.BooleanUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.File;
+import java.util.*;
+
+public class JavaUndertowServerCodegen extends AbstractJavaCodegen {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(JavaUndertowServerCodegen.class);
+
+    protected String title = "OpenAPI Undertow Server";
+    protected String implFolder = "src/main/java";
+
+    public JavaUndertowServerCodegen() {
+        super();
+
+        sourceFolder = "src/main/java";
+        apiTestTemplateFiles.clear(); // TODO: add test template
+        embeddedTemplateDir = templateDir = "undertow";
+        invokerPackage = "io.swagger.handler";
+        artifactId = "swagger-undertow-server";
+        dateLibrary = "legacy"; //TODO: add joda support
+
+        // clear model and api doc template as this codegen
+        // does not support auto-generated markdown doc at the moment
+        //TODO: add doc templates
+        modelDocTemplateFiles.remove("model_doc.mustache");
+        apiDocTemplateFiles.remove("api_doc.mustache");
+
+
+        apiPackage = System.getProperty("swagger.codegen.undertow.apipackage", "io.swagger.handler");
+        modelPackage = System.getProperty("swagger.codegen.undertow.modelpackage", "io.swagger.model");
+
+        additionalProperties.put("title", title);
+    }
+
+    @Override
+    public CodegenType getTag() {
+        return CodegenType.SERVER;
+    }
+
+    @Override
+    public String getName() {
+        return "java-undertow-server";
+    }
+
+    @Override
+    public String getHelp() {
+        return "Generates a Java Undertow Server application (beta).";
+    }
+
+    @Override
+    public void processOpts() {
+        super.processOpts();
+
+        apiTemplateFiles.remove("api.mustache");
+
+        writeOptional(outputFolder, new SupportingFile("pom.mustache", "", "pom.xml"));
+        writeOptional(outputFolder, new SupportingFile("README.mustache", "", "README.md"));
+
+        // keep the yaml in config folder for framework validation.
+        supportingFiles.add(new SupportingFile("openapi.mustache", ("src.main.resources.config").replace(".", java.io.File.separator), "openapi.json"));
+        supportingFiles.add(new SupportingFile("handler.mustache", ("src.main.java.io.swagger.handler").replace(".", java.io.File.separator), "PathHandlerProvider.java"));
+        supportingFiles.add(new SupportingFile("service.mustache", ("src.main.resources.META-INF.services").replace(".", java.io.File.separator), "com.networknt.server.HandlerProvider"));
+
+        // configuration files
+        supportingFiles.add(new SupportingFile("server.json", ("src.main.resources.config").replace(".", java.io.File.separator), "server.json"));
+        supportingFiles.add(new SupportingFile("security.json", ("src.main.resources.config").replace(".", java.io.File.separator), "security.json"));
+        supportingFiles.add(new SupportingFile("primary.crt", ("src.main.resources.config.oauth").replace(".", java.io.File.separator), "primary.crt"));
+
+    }
+
+    @Override
+    public Map<String, Object> postProcessOperations(Map<String, Object> objs) {
+        Map<String, Object> operations = (Map<String, Object>) objs.get("operations");
+        if (operations != null) {
+            List<CodegenOperation> ops = (List<CodegenOperation>) operations.get("operation");
+            for (CodegenOperation operation : ops) {
+                if (operation.returnType == null) {
+                    operation.returnType = "Void";
+                } else if (operation.returnType.startsWith("List")) {
+                    String rt = operation.returnType;
+                    int end = rt.lastIndexOf(">");
+                    if (end > 0) {
+                        operation.returnType = rt.substring("List<".length(), end);
+                        operation.returnContainer = "List";
+                    }
+                } else if (operation.returnType.startsWith("Map")) {
+                    String rt = operation.returnType;
+                    int end = rt.lastIndexOf(">");
+                    if (end > 0) {
+                        operation.returnType = rt.substring("Map<".length(), end);
+                        operation.returnContainer = "Map";
+                    }
+                } else if (operation.returnType.startsWith("Set")) {
+                    String rt = operation.returnType;
+                    int end = rt.lastIndexOf(">");
+                    if (end > 0) {
+                        operation.returnType = rt.substring("Set<".length(), end);
+                        operation.returnContainer = "Set";
+                    }
+                }
+            }
+        }
+        return objs;
+    }
+
+    @Override
+    public void postProcessModelProperty(CodegenModel model, CodegenProperty property) {
+        super.postProcessModelProperty(model, property);
+
+        //Add imports for Jackson
+        if (!BooleanUtils.toBoolean(model.isEnum)) {
+            model.imports.add("JsonProperty");
+
+            if (BooleanUtils.toBoolean(model.hasEnums)) {
+                model.imports.add("JsonValue");
+            }
+        }
+    }
+
+    @Override
+    public Map<String, Object> postProcessModelsEnum(Map<String, Object> objs) {
+        objs = super.postProcessModelsEnum(objs);
+
+        //Add imports for Jackson
+        List<Map<String, String>> imports = (List<Map<String, String>>) objs.get("imports");
+        List<Object> models = (List<Object>) objs.get("models");
+        for (Object _mo : models) {
+            Map<String, Object> mo = (Map<String, Object>) _mo;
+            CodegenModel cm = (CodegenModel) mo.get("model");
+            // for enum model
+            if (Boolean.TRUE.equals(cm.isEnum) && cm.allowableValues != null) {
+                cm.imports.add(importMapping.get("JsonValue"));
+                Map<String, String> item = new HashMap<String, String>();
+                item.put("import", importMapping.get("JsonValue"));
+                imports.add(item);
+            }
+        }
+
+        return objs;
+    }
+
+    public String apiFilename(String templateName, String tag) {
+        String result = super.apiFilename(templateName, tag);
+
+        if (templateName.endsWith("api.mustache")) {
+            int ix = result.indexOf(sourceFolder);
+            String beg = result.substring(0, ix);
+            String end = result.substring(ix + sourceFolder.length());
+            new java.io.File(beg + implFolder).mkdirs();
+            result = beg + implFolder + end;
+        }
+        return result;
+    }
+
+    @Override
+    public Map<String, Object> postProcessSupportingFileData(Map<String, Object> objs) {
+        generateJSONSpecFile(objs);
+        return super.postProcessSupportingFileData(objs);
+    }
+
+    @Override
+    public String toApiName(String name) {
+        if (name.length() == 0) {
+            return "DefaultHandler";
+        }
+        name = name.replaceAll("[^a-zA-Z0-9]+", "_"); // FIXME: a parameter should not be assigned. Also declare the methods parameters as 'final'.
+        return camelize(name) + "Handler";
+    }
+}
diff --git a/modules/openapi-generator/src/main/resources/META-INF/services/org.openapitools.codegen.CodegenConfig b/modules/openapi-generator/src/main/resources/META-INF/services/org.openapitools.codegen.CodegenConfig
index cb1d27bc17d..4942ebd58f1 100644
--- a/modules/openapi-generator/src/main/resources/META-INF/services/org.openapitools.codegen.CodegenConfig
+++ b/modules/openapi-generator/src/main/resources/META-INF/services/org.openapitools.codegen.CodegenConfig
@@ -37,6 +37,7 @@ org.openapitools.codegen.languages.JavaInflectorServerCodegen
 org.openapitools.codegen.languages.JavaMSF4JServerCodegen
 org.openapitools.codegen.languages.JavaPKMSTServerCodegen
 org.openapitools.codegen.languages.JavaPlayFrameworkCodegen
+org.openapitools.codegen.languages.JavaUndertowServerCodegen
 org.openapitools.codegen.languages.JavaVertXServerCodegen
 org.openapitools.codegen.languages.JavaCXFServerCodegen
 org.openapitools.codegen.languages.JavaJAXRSCXFCDIServerCodegen
diff --git a/modules/openapi-generator/src/main/resources/undertow/swagger.mustache b/modules/openapi-generator/src/main/resources/undertow/openapi.mustache
similarity index 100%
rename from modules/openapi-generator/src/main/resources/undertow/swagger.mustache
rename to modules/openapi-generator/src/main/resources/undertow/openapi.mustache