diff --git a/docs/generators/scala-akka-http-server.md b/docs/generators/scala-akka-http-server.md
index 925d6565330..7e056315f61 100644
--- a/docs/generators/scala-akka-http-server.md
+++ b/docs/generators/scala-akka-http-server.md
@@ -61,6 +61,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 <li>Any</li>
 <li>Array</li>
 <li>Boolean</li>
+<li>Byte</li>
 <li>Double</li>
 <li>Float</li>
 <li>Int</li>
diff --git a/docs/generators/scala-akka.md b/docs/generators/scala-akka.md
index 4976275245f..683fbef2167 100644
--- a/docs/generators/scala-akka.md
+++ b/docs/generators/scala-akka.md
@@ -56,6 +56,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 <li>Any</li>
 <li>Array</li>
 <li>Boolean</li>
+<li>Byte</li>
 <li>Double</li>
 <li>Float</li>
 <li>Int</li>
diff --git a/docs/generators/scala-gatling.md b/docs/generators/scala-gatling.md
index 55ce8c23d67..414715926d2 100644
--- a/docs/generators/scala-gatling.md
+++ b/docs/generators/scala-gatling.md
@@ -56,6 +56,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 <li>Any</li>
 <li>Array</li>
 <li>Boolean</li>
+<li>Byte</li>
 <li>Double</li>
 <li>Float</li>
 <li>Int</li>
diff --git a/docs/generators/scala-httpclient-deprecated.md b/docs/generators/scala-httpclient-deprecated.md
index b130d49947e..15bf6f6e26f 100644
--- a/docs/generators/scala-httpclient-deprecated.md
+++ b/docs/generators/scala-httpclient-deprecated.md
@@ -56,6 +56,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 <li>Any</li>
 <li>Array</li>
 <li>Boolean</li>
+<li>Byte</li>
 <li>Double</li>
 <li>Float</li>
 <li>Int</li>
diff --git a/docs/generators/scala-lagom-server.md b/docs/generators/scala-lagom-server.md
index e0f1e2ddee3..8dc2075e377 100644
--- a/docs/generators/scala-lagom-server.md
+++ b/docs/generators/scala-lagom-server.md
@@ -56,6 +56,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 <li>Any</li>
 <li>Array</li>
 <li>Boolean</li>
+<li>Byte</li>
 <li>Double</li>
 <li>Float</li>
 <li>Int</li>
diff --git a/docs/generators/scala-play-server.md b/docs/generators/scala-play-server.md
index d734fed60c2..7be64e0f108 100644
--- a/docs/generators/scala-play-server.md
+++ b/docs/generators/scala-play-server.md
@@ -64,6 +64,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 <li>Any</li>
 <li>Array</li>
 <li>Boolean</li>
+<li>Byte</li>
 <li>Double</li>
 <li>Float</li>
 <li>Int</li>
diff --git a/docs/generators/scala-sttp.md b/docs/generators/scala-sttp.md
index 8a8b5d33c26..a0cd2044ea1 100644
--- a/docs/generators/scala-sttp.md
+++ b/docs/generators/scala-sttp.md
@@ -62,6 +62,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 <li>Any</li>
 <li>Array</li>
 <li>Boolean</li>
+<li>Byte</li>
 <li>Double</li>
 <li>Float</li>
 <li>Int</li>
diff --git a/docs/generators/scalatra.md b/docs/generators/scalatra.md
index d3a9b514913..a7a657bce95 100644
--- a/docs/generators/scalatra.md
+++ b/docs/generators/scalatra.md
@@ -57,6 +57,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 <li>Any</li>
 <li>Array</li>
 <li>Boolean</li>
+<li>Byte</li>
 <li>Double</li>
 <li>Float</li>
 <li>Int</li>
diff --git a/docs/generators/scalaz.md b/docs/generators/scalaz.md
index 25355390e08..41b6240df6d 100644
--- a/docs/generators/scalaz.md
+++ b/docs/generators/scalaz.md
@@ -56,6 +56,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 <li>Any</li>
 <li>Array</li>
 <li>Boolean</li>
+<li>Byte</li>
 <li>Double</li>
 <li>Float</li>
 <li>Int</li>
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
index 43d974391b6..b7d31d9fce5 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
@@ -1580,6 +1580,7 @@ public class DefaultCodegen implements CodegenConfig {
         typeMapping.put("char", "String");
         typeMapping.put("object", "Object");
         typeMapping.put("integer", "Integer");
+        // FIXME: java specific type should be in Java Based Abstract Impl's
         typeMapping.put("ByteArray", "byte[]");
         typeMapping.put("binary", "File");
         typeMapping.put("file", "File");
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java
index f15950eda2a..65ec72caca6 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java
@@ -73,7 +73,8 @@ public abstract class AbstractScalaCodegen extends DefaultCodegen {
                 "List",
                 "Seq",
                 "Map",
-                "Array"));
+                "Array",
+                "Byte"));
 
         reservedWords.addAll(Arrays.asList(
                 "abstract",
@@ -118,6 +119,10 @@ public abstract class AbstractScalaCodegen extends DefaultCodegen {
                 "yield"
         ));
 
+        // Scala specific openApi types mapping
+        typeMapping.put("ByteArray", "Array[Byte]");
+
+
         importMapping = new HashMap<String, String>();
         importMapping.put("ListBuffer", "scala.collection.mutable.ListBuffer");
         // although Seq is a predef, before Scala 2.13, it _could_ refer to a mutable Seq in some cases.
@@ -344,17 +349,11 @@ public abstract class AbstractScalaCodegen extends DefaultCodegen {
         if (ModelUtils.isSet(p)) {
             openAPIType = "set";
         }
-
-        String type;
+        // don't apply renaming on types from the typeMapping
         if (typeMapping.containsKey(openAPIType)) {
-            type = typeMapping.get(openAPIType);
-            if (languageSpecificPrimitives.contains(type)) {
-                return toModelName(type);
-            }
-        } else {
-            type = openAPIType;
+            return typeMapping.get(openAPIType);
         }
-        return toModelName(type);
+        return toModelName(openAPIType);
     }
 
     @Override
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaSttpClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaSttpClientCodegen.java
index 4ad5505871c..dd0dca689fb 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaSttpClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaSttpClientCodegen.java
@@ -125,6 +125,7 @@ public class ScalaSttpClientCodegen extends AbstractScalaCodegen implements Code
         importMapping.remove("Set");
         importMapping.remove("Map");
 
+        // TODO: there is no specific sttp mapping. All Scala Type mappings should be in AbstractScala
         typeMapping = new HashMap<>();
         typeMapping.put("array", "Seq");
         typeMapping.put("set", "Set");
@@ -144,7 +145,6 @@ public class ScalaSttpClientCodegen extends AbstractScalaCodegen implements Code
         typeMapping.put("number", "Double");
         typeMapping.put("decimal", "BigDecimal");
         typeMapping.put("ByteArray", "Array[Byte]");
-        typeMapping.put("ArrayByte", "Array[Byte]");
 
         instantiationTypes.put("array", "ListBuffer");
         instantiationTypes.put("map", "Map");
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/AbstractScalaCodegenTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/AbstractScalaCodegenTest.java
index 97e9c3102e8..ce62184a0d3 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/AbstractScalaCodegenTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/AbstractScalaCodegenTest.java
@@ -1,5 +1,7 @@
 package org.openapitools.codegen.scala;
 
+import io.swagger.v3.oas.models.media.ObjectSchema;
+import io.swagger.v3.oas.models.media.Schema;
 import org.openapitools.codegen.CodegenConstants;
 import org.openapitools.codegen.languages.AbstractScalaCodegen;
 import org.testng.Assert;
@@ -95,4 +97,21 @@ public class AbstractScalaCodegenTest {
         Assert.assertFalse(fakeScalaCodegen.importMapping().containsKey("BigInt"),
                 "BigInt is a Scala type and must not be imported");
     }
+
+    @Test
+    void checkScalaTypeDeclaration() {
+
+        final AbstractScalaCodegen codegen = new P_AbstractScalaCodegen();
+
+        Schema<?> byteArraySchema = new ObjectSchema();
+        byteArraySchema.setType("string");
+        byteArraySchema.setFormat("byte");
+        byteArraySchema.setDescription("Schema with byte string");
+
+        Assert.assertEquals(codegen.getTypeDeclaration(byteArraySchema), "Array[Byte]",
+                "OpenApi File type represented as byte string should be represented as Array[Byte] scala type");
+
+    }
+
+
 }
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpBooleanPropertyTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpBooleanPropertyTest.java
index c500dda7706..010fd99f564 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpBooleanPropertyTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpBooleanPropertyTest.java
@@ -1,7 +1,7 @@
 package org.openapitools.codegen.scala;
 
-import org.junit.Assert;
-import org.junit.Test;
+import org.testng.Assert;
+import org.testng.annotations.Test;
 import org.openapitools.codegen.languages.ScalaSttpClientCodegen;
 
 import java.util.HashMap;
@@ -14,7 +14,7 @@ public class SttpBooleanPropertyTest {
         Map<String, Object> additionalProperties = new HashMap<>();
         booleanProperty.updateAdditionalProperties(additionalProperties);
 
-        Assert.assertEquals(false, additionalProperties.get("k1"));
+        Assert.assertEquals(additionalProperties.get("k1"), false);
     }
 
     @Test
@@ -24,6 +24,6 @@ public class SttpBooleanPropertyTest {
         additionalProperties.put("k1", true);
         booleanProperty.updateAdditionalProperties(additionalProperties);
 
-        Assert.assertEquals(true, additionalProperties.get("k1"));
+        Assert.assertEquals(additionalProperties.get("k1"), true);
     }
 }
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpCodegenTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpCodegenTest.java
index 60bf063f3c5..653fc342d82 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpCodegenTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpCodegenTest.java
@@ -1,8 +1,8 @@
 package org.openapitools.codegen.scala;
 
 import org.openapitools.codegen.languages.ScalaSttpClientCodegen;
-import org.junit.Assert;
-import org.junit.Test;
+import org.testng.Assert;
+import org.testng.annotations.Test;
 
 import io.swagger.v3.oas.models.media.Schema;
 
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpJsonLibraryPropertyTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpJsonLibraryPropertyTest.java
index d8473cb8f5d..23ae32e0511 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpJsonLibraryPropertyTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpJsonLibraryPropertyTest.java
@@ -1,7 +1,7 @@
 package org.openapitools.codegen.scala;
 
-import org.junit.Assert;
-import org.junit.Test;
+import org.testng.Assert;
+import org.testng.annotations.Test;
 import org.openapitools.codegen.languages.ScalaSttpClientCodegen;
 
 import java.util.HashMap;
@@ -13,8 +13,8 @@ public class SttpJsonLibraryPropertyTest {
         ScalaSttpClientCodegen.JsonLibraryProperty property = new ScalaSttpClientCodegen.JsonLibraryProperty();
         Map<String, Object> additionalProperties = new HashMap<>();
         property.updateAdditionalProperties(additionalProperties);
-        Assert.assertEquals(true, additionalProperties.get("json4s"));
-        Assert.assertEquals(false, additionalProperties.get("circe"));
+        Assert.assertEquals(additionalProperties.get("json4s"), true);
+        Assert.assertEquals(additionalProperties.get("circe"), false);
     }
 
     @Test
@@ -23,8 +23,8 @@ public class SttpJsonLibraryPropertyTest {
         Map<String, Object> additionalProperties = new HashMap<>();
         additionalProperties.put("jsonLibrary", "json4s");
         property.updateAdditionalProperties(additionalProperties);
-        Assert.assertEquals(true, additionalProperties.get("json4s"));
-        Assert.assertEquals(false, additionalProperties.get("circe"));
+        Assert.assertEquals(additionalProperties.get("json4s"), true);
+        Assert.assertEquals(additionalProperties.get("circe"), false);
     }
 
     @Test
@@ -33,7 +33,7 @@ public class SttpJsonLibraryPropertyTest {
         Map<String, Object> additionalProperties = new HashMap<>();
         additionalProperties.put("jsonLibrary", "circe");
         property.updateAdditionalProperties(additionalProperties);
-        Assert.assertEquals(false, additionalProperties.get("json4s"));
-        Assert.assertEquals(true, additionalProperties.get("circe"));
+        Assert.assertEquals(additionalProperties.get("json4s"), false);
+        Assert.assertEquals(additionalProperties.get("circe"), true);
     }
 }
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpPackagePropertyTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpPackagePropertyTest.java
index 7aa45197522..8bbdb684f1c 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpPackagePropertyTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpPackagePropertyTest.java
@@ -1,7 +1,7 @@
 package org.openapitools.codegen.scala;
 
-import org.junit.Assert;
-import org.junit.Test;
+import org.testng.Assert;
+import org.testng.annotations.Test;
 import org.openapitools.codegen.CodegenConstants;
 import org.openapitools.codegen.languages.ScalaSttpClientCodegen;
 
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpStringPropertyTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpStringPropertyTest.java
index f0db3bdafd3..22be5feecc8 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpStringPropertyTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/scala/SttpStringPropertyTest.java
@@ -1,7 +1,7 @@
 package org.openapitools.codegen.scala;
 
-import org.junit.Assert;
-import org.junit.Test;
+import org.testng.Assert;
+import org.testng.annotations.Test;
 import org.openapitools.codegen.languages.ScalaSttpClientCodegen;
 
 import java.util.HashMap;
@@ -10,21 +10,21 @@ import java.util.Map;
 public class SttpStringPropertyTest {
 
     @Test
-    public void shouldUseDefaultValueIfAdditionalPropertiesAreEmpty(){
+    public void shouldUseDefaultValueIfAdditionalPropertiesAreEmpty() {
         ScalaSttpClientCodegen.StringProperty property = new ScalaSttpClientCodegen.StringProperty("k1", "desc", "default");
         Map<String, Object> additionalProperties = new HashMap<>();
         property.updateAdditionalProperties(additionalProperties);
 
-        Assert.assertEquals("default", additionalProperties.get("k1"));
+        Assert.assertEquals(additionalProperties.get("k1"), "default");
     }
 
     @Test
-    public void shouldUseGivenValueIfProvided(){
+    public void shouldUseGivenValueIfProvided() {
         ScalaSttpClientCodegen.StringProperty property = new ScalaSttpClientCodegen.StringProperty("k1", "desc", "default");
         Map<String, Object> additionalProperties = new HashMap<>();
         additionalProperties.put("k1", "custom");
         property.updateAdditionalProperties(additionalProperties);
 
-        Assert.assertEquals("custom", additionalProperties.get("k1"));
+        Assert.assertEquals(additionalProperties.get("k1"), "custom");
     }
 }
diff --git a/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/ApiInvoker.scala b/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/ApiInvoker.scala
new file mode 100644
index 00000000000..f04c9fa6a1e
--- /dev/null
+++ b/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/ApiInvoker.scala
@@ -0,0 +1,237 @@
+/**
+ * OpenAPI Petstore
+ * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+package org.openapitools.example.invoker
+
+import com.sun.jersey.api.client.Client
+import com.sun.jersey.api.client.ClientResponse
+import com.sun.jersey.api.client.config.ClientConfig
+import com.sun.jersey.api.client.config.DefaultClientConfig
+import com.sun.jersey.api.client.filter.LoggingFilter
+
+import com.sun.jersey.core.util.MultivaluedMapImpl
+import com.sun.jersey.multipart.FormDataMultiPart
+import com.sun.jersey.multipart.file.FileDataBodyPart
+
+import java.io.File
+import java.net.URLEncoder
+import java.util.UUID
+import javax.ws.rs.core.MediaType
+
+import scala.collection.JavaConverters._
+import scala.collection.mutable
+
+import com.fasterxml.jackson.module.scala.DefaultScalaModule
+import com.fasterxml.jackson.datatype.joda.JodaModule
+import com.fasterxml.jackson.core.JsonGenerator.Feature
+import com.fasterxml.jackson.databind._
+import com.fasterxml.jackson.annotation._
+import com.fasterxml.jackson.databind.annotation.JsonSerialize
+
+object ScalaJsonUtil {
+  def getJsonMapper: ObjectMapper = {
+    val mapper = new ObjectMapper()
+    mapper.registerModule(new DefaultScalaModule())
+    mapper.registerModule(new JodaModule())
+    mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL)
+    mapper.setSerializationInclusion(JsonInclude.Include.NON_DEFAULT)
+    mapper.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false)
+    mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
+    mapper.setSerializationInclusion(JsonInclude.Include.NON_EMPTY)
+    mapper
+  }
+}
+
+class ApiInvoker(val mapper: ObjectMapper = ScalaJsonUtil.getJsonMapper,
+  httpHeaders: mutable.HashMap[String, String] = mutable.HashMap(),
+  hostMap: mutable.HashMap[String, Client] = mutable.HashMap(),
+  asyncHttpClient: Boolean = false,
+  authScheme: String = "",
+  authPreemptive: Boolean = false
+) {
+
+  var defaultHeaders: mutable.HashMap[String, String] = httpHeaders
+
+  def escape(value: String): String = {
+    URLEncoder.encode(value, "utf-8").replaceAll("\\+", "%20")
+  }
+  def escape(values: List[String]): String = {
+     values.map(escape).mkString(",")
+  }
+
+  def escape(value: Long): String = value.toString
+  def escape(value: Double): String = value.toString
+  def escape(value: Float): String = value.toString
+  def escape(value: UUID): String = value.toString
+
+  def deserialize(json: String, containerType: String, cls: Class[_]) = {
+    if (cls == classOf[String]) {
+      json match {
+        case s: String =>
+          if (s.startsWith("\"") && s.endsWith("\"") && s.length > 1) {
+            s.substring(1, s.length - 1)
+          } else {
+            s
+          }
+        case _ => null
+      }
+    } else {
+      containerType.toLowerCase match {
+        case "array" =>
+          val typeInfo = mapper.getTypeFactory.constructCollectionType(classOf[java.util.List[_]], cls)
+          val response = mapper.readValue(json, typeInfo).asInstanceOf[java.util.List[_]]
+          response.asScala.toList
+        case "list" =>
+          val typeInfo = mapper.getTypeFactory.constructCollectionType(classOf[java.util.List[_]], cls)
+          val response = mapper.readValue(json, typeInfo).asInstanceOf[java.util.List[_]]
+          response.asScala.toList
+        case _ =>
+          json match {
+            case e: String if "\"\"" == e => null
+            case _ => mapper.readValue(json, cls)
+          }
+      }
+    }
+  }
+
+  def serialize(obj: AnyRef): String = {
+    if (obj != null) {
+      obj match {
+        case e: List[_] => mapper.writeValueAsString(obj.asInstanceOf[List[_]].asJava)
+        case _ => mapper.writeValueAsString(obj)
+      }
+    } else {
+        null
+    }
+  }
+
+  def invokeApi(
+    host: String,
+    path: String,
+    method: String,
+    queryParams: Map[String, String],
+    formParams: Map[String, String],
+    body: AnyRef,
+    headerParams: Map[String, String],
+    contentType: String
+): String = {
+    val client = getClient(host)
+
+    val querystring = queryParams.filter(k => k._2 != null).map(k => escape(k._1) + "=" + escape(k._2)).mkString("?", "&", "")
+    val builder = client.resource(host + path + querystring).accept(contentType)
+    headerParams.map(p => builder.header(p._1, p._2))
+    defaultHeaders.foreach(p => {
+      if (!headerParams.contains(p._1) && p._2 != null) {
+        builder.header(p._1, p._2)
+      }
+    })
+    var formData: MultivaluedMapImpl = null
+    if (contentType == "application/x-www-form-urlencoded") {
+      formData = new MultivaluedMapImpl()
+      formParams.foreach(p => formData.add(p._1, p._2))
+    }
+
+    val response: ClientResponse = method match {
+      case "GET" => builder.get(classOf[ClientResponse])
+      case "POST" =>
+        if (formData != null && formData.size() > 0) {
+            builder.post(classOf[ClientResponse], formData)
+        } else if (body != null && body.isInstanceOf[File]) {
+          val file = body.asInstanceOf[File]
+          val form = new FormDataMultiPart()
+          form.field("filename", file.getName)
+          form.bodyPart(new FileDataBodyPart("file", file, MediaType.MULTIPART_FORM_DATA_TYPE))
+          builder.post(classOf[ClientResponse], form)
+        } else {
+          if (body == null) {
+            builder.post(classOf[ClientResponse], serialize(body))
+          } else {
+            builder.`type`(contentType).post(classOf[ClientResponse], serialize(body))
+          }
+        }
+      case "PUT" =>
+        if (formData != null) {
+            builder.post(classOf[ClientResponse], formData)
+        } else if (body == null) {
+            builder.put(classOf[ClientResponse], null)
+        } else {
+            builder.`type`(contentType).put(classOf[ClientResponse], serialize(body))
+        }
+      case "DELETE" => builder.delete(classOf[ClientResponse])
+      case "PATCH" =>
+        if(formData != null) {
+          builder.header("X-HTTP-Method-Override", "PATCH").post(classOf[ClientResponse], formData)
+        } else if(body == null) {
+          builder.header("X-HTTP-Method-Override", "PATCH").post(classOf[ClientResponse], null)
+        } else {
+          builder.header("X-HTTP-Method-Override", "PATCH").`type`(contentType).post(classOf[ClientResponse], serialize(body))
+        }
+      case _ => null
+    }
+    response.getStatusInfo.getStatusCode match {
+      case 204 => ""
+      case code: Int if Range(200, 299).contains(code) =>
+        if (response.hasEntity) {
+          response.getEntity(classOf[String])
+        } else {
+          ""
+        }
+      case _ =>
+        val entity = if (response.hasEntity) {
+          response.getEntity(classOf[String])
+        } else {
+          "no data"
+        }
+        throw new ApiException(response.getStatusInfo.getStatusCode, entity)
+    }
+  }
+
+  def getClient(host: String): Client = {
+    if (hostMap.contains(host)) {
+      hostMap(host)
+    } else {
+      val client = newClient(host)
+      // client.addFilter(new LoggingFilter())
+      hostMap += host -> client
+      client
+    }
+  }
+
+  def newClient(host: String): Client = if (asyncHttpClient) {
+    import com.ning.http.client.Realm
+    import org.sonatype.spice.jersey.client.ahc.AhcHttpClient
+    import org.sonatype.spice.jersey.client.ahc.config.DefaultAhcConfig
+
+    val config: DefaultAhcConfig = new DefaultAhcConfig()
+    if (!authScheme.isEmpty) {
+      val authSchemeEnum = Realm.AuthScheme.valueOf(authScheme)
+      config
+        .getAsyncHttpClientConfigBuilder
+        .setRealm(new Realm.RealmBuilder().setScheme(authSchemeEnum)
+        .setUsePreemptiveAuth(authPreemptive).build)
+    }
+    AhcHttpClient.create(config)
+  } else {
+     Client.create()
+  }
+}
+
+object ApiInvoker extends ApiInvoker(
+  mapper = ScalaJsonUtil.getJsonMapper,
+  httpHeaders = mutable.HashMap(),
+  hostMap = mutable.HashMap(),
+  asyncHttpClient = false,
+  authScheme = "",
+  authPreemptive = false
+)
+
+class ApiException(val code: Int, msg: String) extends RuntimeException(msg)
diff --git a/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/AsyncClient.scala b/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/AsyncClient.scala
new file mode 100644
index 00000000000..60e423b51cb
--- /dev/null
+++ b/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/AsyncClient.scala
@@ -0,0 +1,20 @@
+package org.openapitools.example.invoker
+
+import org.openapitools.example.api._
+
+import com.wordnik.swagger.client._
+
+import java.io.Closeable
+
+class AsyncClient(config: SwaggerConfig) extends Closeable {
+  lazy val locator: ServiceLocator = config.locator
+  lazy val name: String = config.name
+
+  private[this] val client = transportClient
+
+  protected def transportClient: TransportClient = new RestClient(config)
+
+  def close() {
+    client.close()
+  }
+}
diff --git a/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/model/InlineObject.scala b/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/model/InlineObject.scala
new file mode 100644
index 00000000000..071b023e1a5
--- /dev/null
+++ b/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/model/InlineObject.scala
@@ -0,0 +1,22 @@
+/**
+ * OpenAPI Petstore
+ * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+package org.openapitools.client.model
+
+
+case class InlineObject (
+  // Updated name of the pet
+  name: Option[String] = None,
+  // Updated status of the pet
+  status: Option[String] = None
+)
+
diff --git a/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/model/InlineObject1.scala b/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/model/InlineObject1.scala
new file mode 100644
index 00000000000..520d5858eb9
--- /dev/null
+++ b/samples/client/petstore/scala-httpclient-deprecated/src/main/scala/org/openapitools/client/model/InlineObject1.scala
@@ -0,0 +1,23 @@
+/**
+ * OpenAPI Petstore
+ * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+package org.openapitools.client.model
+
+import java.io.File
+
+case class InlineObject1 (
+  // Additional data to pass to server
+  additionalMetadata: Option[String] = None,
+  // file to upload
+  file: Option[File] = None
+)
+