diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractEiffelCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractEiffelCodegen.java
index 863f6b25422..453f67a5711 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractEiffelCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractEiffelCodegen.java
@@ -266,7 +266,7 @@ public abstract class AbstractEiffelCodegen extends DefaultCodegen implements Co
             ArraySchema ap = (ArraySchema) p;
             Schema inner = ap.getItems();
             return "LIST [" + getTypeDeclaration(inner) + "]";
-        } else if (p instanceof MapSchema) {
+        } else if (isMapSchema(p)) {
             Schema inner = (Schema) p.getAdditionalProperties();
 
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
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 96aa0346232..d254ded12d2 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
@@ -185,7 +185,7 @@ public abstract class AbstractScalaCodegen extends DefaultCodegen {
 
     @Override
     public String toInstantiationType(Schema p) {
-        if (p instanceof MapSchema) {
+        if (isMapSchema(p)) {
             String inner = getSchemaType((Schema)p.getAdditionalProperties());
             return instantiationTypes.get("map") + "[String, " + inner + "]";
         } else if (p instanceof ArraySchema) {
@@ -211,7 +211,7 @@ public abstract class AbstractScalaCodegen extends DefaultCodegen {
             return "null";
         } else if (p instanceof IntegerSchema) {
             return "null";
-        } else if (p instanceof MapSchema) {
+        } else if (isMapSchema(p)) {
             MapSchema ap = (MapSchema) p;
             String inner = getSchemaType((Schema) ap.getAdditionalProperties());
             return "new HashMap[String, " + inner + "]() ";
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractTypeScriptClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractTypeScriptClientCodegen.java
index dcca0121cd4..78a937e19bf 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractTypeScriptClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractTypeScriptClientCodegen.java
@@ -235,7 +235,7 @@ public abstract class AbstractTypeScriptClientCodegen extends DefaultCodegen imp
             ArraySchema mp1 = (ArraySchema) p;
             inner = mp1.getItems();
             return this.getSchemaType(p) + "<" + this.getParameterDataType(parameter, inner) + ">";
-        } else if (p instanceof MapSchema) {
+        } else if (isMapSchema(p)) {
             inner = (Schema) p.getAdditionalProperties();
             return "{ [key: string]: " + this.getParameterDataType(parameter, inner) + "; }";
         } else if (p instanceof StringSchema) {
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppPistacheServerCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppPistacheServerCodegen.java
index 7ae0cfa735c..70f2c27fcd8 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppPistacheServerCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppPistacheServerCodegen.java
@@ -298,7 +298,7 @@ public class CppPistacheServerCodegen extends AbstractCppCodegen {
                 return "0L";
             }
             return "0";
-        } else if (p instanceof MapSchema) {
+        } else if (isMapSchema(p)) {
             MapSchema ap = (MapSchema) p;
             String inner = getSchemaType((Schema) ap.getAdditionalProperties());
             return "std::map<std::string, " + inner + ">()";
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppQt5ClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppQt5ClientCodegen.java
index c5aeefbf197..f2dbc94f749 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppQt5ClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppQt5ClientCodegen.java
@@ -322,7 +322,7 @@ public class CppQt5ClientCodegen extends AbstractCppCodegen implements CodegenCo
                 return "0L";
             }
             return "0";
-        } else if (p instanceof MapSchema) {
+        } else if (isMapSchema(p)) {
             Schema inner = (Schema) p.getAdditionalProperties();
             return "new QMap<QString, " + getTypeDeclaration(inner) + ">()";
         } else if (p instanceof ArraySchema) {
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestClientCodegen.java
index 5694907b76c..8352400f7f5 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestClientCodegen.java
@@ -313,7 +313,7 @@ public class CppRestClientCodegen extends AbstractCppCodegen {
                 return "0L";
             }
             return "0";
-        } else if (p instanceof MapSchema) {
+        } else if (isMapSchema(p)) {
             MapSchema ap = (MapSchema) p;
             String inner = getSchemaType((Schema) ap.getAdditionalProperties());
             return "std::map<utility::string_t, " + inner + ">()";
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestbedServerCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestbedServerCodegen.java
index 49f1812413e..825a868d9e5 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestbedServerCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestbedServerCodegen.java
@@ -301,7 +301,7 @@ public class CppRestbedServerCodegen extends AbstractCppCodegen {
                 return "0L";
             }
             return "0";
-        } else if (p instanceof MapSchema) {
+        } else if (isMapSchema(p)) {
             MapSchema ap = (MapSchema) p;
             String inner = getSchemaType((Schema) ap.getAdditionalProperties());
             return "std::map<std::string, " + inner + ">()";
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppTizenClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppTizenClientCodegen.java
index 15b9762cb86..2a5cacb5d54 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppTizenClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppTizenClientCodegen.java
@@ -123,7 +123,7 @@ public class CppTizenClientCodegen extends DefaultCodegen implements CodegenConf
 
     @Override
     public String toInstantiationType(Schema p) {
-        if (p instanceof MapSchema) {
+        if (isMapSchema(p)) {
             return instantiationTypes.get("map");
         } else if (p instanceof ArraySchema) {
             return instantiationTypes.get("array");
@@ -209,7 +209,7 @@ public class CppTizenClientCodegen extends DefaultCodegen implements CodegenConf
                 return "long(0)";
             }
             return "int(0)";
-        } else if (p instanceof MapSchema) {
+        } else if (isMapSchema(p)) {
             return "new std::map()";
         } else if (p instanceof ArraySchema) {
             return "new std::list()";
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ElmClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ElmClientCodegen.java
index 85a882ca0a5..fbea9c1945b 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ElmClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ElmClientCodegen.java
@@ -459,7 +459,7 @@ public class ElmClientCodegen extends DefaultCodegen implements CodegenConfig {
             ArraySchema ap = (ArraySchema) p;
             Schema inner = ap.getItems();
             return getTypeDeclaration(inner);
-        } else if (p instanceof MapSchema) {
+        } else if (isMapSchema(p)) {
             Schema inner = (Schema) p.getAdditionalProperties();
             return getTypeDeclaration(inner);
         }
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellHttpClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellHttpClientCodegen.java
index 4abd7540361..cacc0c3757f 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellHttpClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellHttpClientCodegen.java
@@ -553,7 +553,7 @@ public class HaskellHttpClientCodegen extends DefaultCodegen implements CodegenC
 
     @Override
     public String toInstantiationType(Schema p) {
-        if (p instanceof MapSchema) {
+        if (isMapSchema(p)) {
             MapSchema ap = (MapSchema) p;
             Schema additionalProperties2 = (Schema) ap.getAdditionalProperties();
             String type = additionalProperties2.getType();
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellServantCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellServantCodegen.java
index 1576eda871e..2609b3f6532 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellServantCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellServantCodegen.java
@@ -306,7 +306,7 @@ public class HaskellServantCodegen extends DefaultCodegen implements CodegenConf
 
     @Override
     public String toInstantiationType(Schema p) {
-        if (p instanceof MapSchema) {
+        if (isMapSchema(p)) {
             MapSchema ap = (MapSchema) p;
             Schema additionalProperties2 = (Schema) ap.getAdditionalProperties();
             String type = additionalProperties2.getType();
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/LuaClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/LuaClientCodegen.java
index 2ec9a1e3ddc..e18c8b6940e 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/LuaClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/LuaClientCodegen.java
@@ -323,7 +323,7 @@ public class LuaClientCodegen extends DefaultCodegen implements CodegenConfig {
             ArraySchema ap = (ArraySchema) p;
             Schema inner = ap.getItems();
             return getTypeDeclaration(inner);
-        } else if (p instanceof MapSchema) {
+        } else if (isMapSchema(p)) {
             Schema inner = (Schema) p.getAdditionalProperties();
             return getTypeDeclaration(inner);
         }
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ObjcClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ObjcClientCodegen.java
index bfa6e697d02..ea20466650d 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ObjcClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ObjcClientCodegen.java
@@ -296,7 +296,7 @@ public class ObjcClientCodegen extends DefaultCodegen implements CodegenConfig {
 
     @Override
     public String toInstantiationType(Schema p) {
-        if (p instanceof MapSchema) {
+        if (isMapSchema(p)) {
             return instantiationTypes.get("map");
         } else if (p instanceof ArraySchema) {
             return instantiationTypes.get("array");
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift3Codegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift3Codegen.java
index af7990fd946..c902be82ffd 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift3Codegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift3Codegen.java
@@ -373,7 +373,7 @@ public class Swift3Codegen extends DefaultCodegen implements CodegenConfig {
 
     @Override
     public String toInstantiationType(Schema p) {
-        if (p instanceof MapSchema) {
+        if (isMapSchema(p)) {
             MapSchema ap = (MapSchema) p;
             String inner = getSchemaType((Schema) ap.getAdditionalProperties());
             return inner;
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift4Codegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift4Codegen.java
index 5bea60cd646..bd291ce1667 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift4Codegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift4Codegen.java
@@ -476,7 +476,7 @@ public class Swift4Codegen extends DefaultCodegen implements CodegenConfig {
 
     @Override
     public String toInstantiationType(Schema prop) {
-        if (prop instanceof MapSchema) {
+        if (isMapSchema(prop)) {
             MapSchema ap = (MapSchema) prop;
             String inner = getSchemaType((Schema) ap.getAdditionalProperties());
             return inner;
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SwiftClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SwiftClientCodegen.java
index 387864c1f08..86bed40c773 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SwiftClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SwiftClientCodegen.java
@@ -351,7 +351,7 @@ public class SwiftClientCodegen extends DefaultCodegen implements CodegenConfig
 
     @Override
     public String toInstantiationType(Schema p) {
-        if (p instanceof MapSchema) {
+        if (isMapSchema(p)) {
             MapSchema ap = (MapSchema) p;
             String inner = getSchemaType((Schema) ap.getAdditionalProperties());
             return "[String:" + inner + "]";