diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CSharpClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CSharpClientCodegen.java
index 771dcf8efa3d..a475c6c9e752 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CSharpClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CSharpClientCodegen.java
@@ -484,6 +484,9 @@ public String toEnumVarName(String value, String datatype) {
         var = WordUtils.capitalizeFully(var);
         var = var.replaceAll("\\W+", "");
 
+        if (var.length() == 0) {
+            return "EMPTY";
+        }
 
         if (var.matches("\\d.*")) {
             return "_" + var;
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavaClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavaClientCodegen.java
index fea63abb1f1e..e1f3ead65b29 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavaClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavaClientCodegen.java
@@ -904,6 +904,9 @@ public String toEnumVarName(String value, String datatype) {
 
         // string
         String var = value.replaceAll("\\W+", "_").replaceAll("_+", "_").toUpperCase(Locale.getDefault());
+        if (var.length() == 0) {
+            return "EMPTY";
+        }
         if (var.matches("\\d.*")) {
             return "_" + var;
         } else {
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PureCloudJavaClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PureCloudJavaClientCodegen.java
index 97c18f2a5ef6..f02714bd8ba5 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PureCloudJavaClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PureCloudJavaClientCodegen.java
@@ -9,6 +9,7 @@
 import org.openapitools.codegen.*;
 import org.openapitools.codegen.templating.mustache.PrefixNumberWithValue;
 import org.openapitools.codegen.templating.mustache.StringReplaceLambda;
+import org.openapitools.codegen.templating.mustache.ReplaceEmptyStringWithValueLambda;
 import org.openapitools.codegen.utils.ModelUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -381,6 +382,7 @@ protected ImmutableMap.Builder<String, Mustache.Lambda> addMustacheLambdas() {
 
         return super.addMustacheLambdas()
                 .put("replace", new StringReplaceLambda(replaceMap))
+                .put("replaceEmptyStringWithEmptyLabel", new ReplaceEmptyStringWithValueLambda("EMPTY"))
                 .put("prefixNumberWithUnderscore", new PrefixNumberWithValue("_", false))
                 .put("prefixNumberWithWord", new PrefixNumberWithValue("NUMBER_", true));
     }
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/templating/mustache/ReplaceEmptyStringWithValueLambda.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/templating/mustache/ReplaceEmptyStringWithValueLambda.java
new file mode 100644
index 000000000000..ebe2f02824a3
--- /dev/null
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/templating/mustache/ReplaceEmptyStringWithValueLambda.java
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2018 OpenAPI-Generator Contributors (https://openapi-generator.tech)
+ * Copyright 2018 SmartBear Software
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.openapitools.codegen.templating.mustache;
+
+import com.samskivert.mustache.Mustache;
+import com.samskivert.mustache.Template;
+
+import java.io.IOException;
+import java.io.Writer;
+import java.util.Locale;
+
+/**
+ * Replace empty string with EMPTY
+ */
+public class ReplaceEmptyStringWithValueLambda implements Mustache.Lambda {
+    private String value = "Empty";
+
+    /**
+     * Constructs a new instance of {@link ReplaceEmptyStringWithValueLambda}
+     */
+    public ReplaceEmptyStringWithValueLambda(String value) {
+        this.value = value;
+    }
+
+    public ReplaceEmptyStringWithValueLambda() {
+    }
+
+    @Override
+    public void execute(Template.Fragment fragment, Writer writer) throws IOException {
+        String text = fragment.execute();
+        if (text == null) {
+            return;
+        }
+        if (text.length() == 0) {
+            text = value;
+        }
+        writer.write(text);
+    }
+}