diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/ApiClient.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/ApiClient.mustache
index c81b9643a10..5c59b7e2ecf 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/ApiClient.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/ApiClient.mustache
@@ -72,6 +72,33 @@ import {{invokerPackage}}.auth.OAuthFlow;
 public class ApiClient {
 
     private String basePath = "{{{basePath}}}";
+    protected List<ServerConfiguration> servers = new ArrayList<ServerConfiguration>({{#servers}}{{#-first}}Arrays.asList(
+{{/-first}}    new ServerConfiguration(
+      "{{{url}}}",
+      "{{{description}}}{{^description}}No description provided{{/description}}",
+      new HashMap<String, ServerVariable>(){{#variables}}{{#-first}} {{
+{{/-first}}        put("{{{name}}}", new ServerVariable(
+          "{{{description}}}{{^description}}No description provided{{/description}}",
+          "{{{defaultValue}}}",
+          new HashSet<String>(
+          {{#enumValues}}
+          {{#-first}}
+            Arrays.asList(
+          {{/-first}}
+              "{{{.}}}"{{^-last}},{{/-last}}
+          {{#-last}}
+            )
+          {{/-last}}
+          {{/enumValues}}
+          )
+        ));
+      {{#-last}}
+      }}{{/-last}}{{/variables}}
+    ){{^-last}},{{/-last}}
+  {{#-last}}
+  ){{/-last}}{{/servers}});
+    protected Integer serverIndex = 0;
+    protected Map<String, String> serverVariables = null;
     private boolean debugging = false;
     private Map<String, String> defaultHeaderMap = new HashMap<String, String>();
     private Map<String, String> defaultCookieMap = new HashMap<String, String>();
@@ -261,6 +288,33 @@ public class ApiClient {
         return this;
     }
 
+    public List<ServerConfiguration> getServers() {
+        return servers;
+    }
+
+    public ApiClient setServers(List<ServerConfiguration> servers) {
+        this.servers = servers;
+        return this;
+    }
+
+    public Integer getServerIndex() {
+        return serverIndex;
+    }
+
+    public ApiClient setServerIndex(Integer serverIndex) {
+        this.serverIndex = serverIndex;
+        return this;
+    }
+
+    public Map<String, String> getServerVariables() {
+        return serverVariables;
+    }
+
+    public ApiClient setServerVariables(Map<String, String> serverVariables) {
+        this.serverVariables = serverVariables;
+        return this;
+    }
+
     /**
      * Get HTTP client
      *
@@ -1399,7 +1453,18 @@ public class ApiClient {
         if (baseUrl != null) {
             url.append(baseUrl).append(path);
         } else {
-            url.append(basePath).append(path);
+            String baseURL;
+            if (serverIndex != null) {
+                if (serverIndex < 0 || serverIndex >= servers.size()) {
+                    throw new ArrayIndexOutOfBoundsException(String.format(
+                    "Invalid index %d when selecting the host settings. Must be less than %d", serverIndex, servers.size()
+                    ));
+                }
+                baseURL = servers.get(serverIndex).URL(serverVariables);
+            } else {
+                baseURL = basePath;
+            }
+            url.append(baseURL).append(path);
         }
 
         if (queryParams != null && !queryParams.isEmpty()) {
diff --git a/samples/client/others/java/okhttp-gson-streaming/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/others/java/okhttp-gson-streaming/src/main/java/org/openapitools/client/ApiClient.java
index a21641307c5..6691f0af402 100644
--- a/samples/client/others/java/okhttp-gson-streaming/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/others/java/okhttp-gson-streaming/src/main/java/org/openapitools/client/ApiClient.java
@@ -61,6 +61,15 @@ import org.openapitools.client.auth.ApiKeyAuth;
 public class ApiClient {
 
     private String basePath = "http://localhost:8082";
+    protected List<ServerConfiguration> servers = new ArrayList<ServerConfiguration>(Arrays.asList(
+    new ServerConfiguration(
+      "http://localhost:8082",
+      "No description provided",
+      new HashMap<String, ServerVariable>()
+    )
+  ));
+    protected Integer serverIndex = 0;
+    protected Map<String, String> serverVariables = null;
     private boolean debugging = false;
     private Map<String, String> defaultHeaderMap = new HashMap<String, String>();
     private Map<String, String> defaultCookieMap = new HashMap<String, String>();
@@ -154,6 +163,33 @@ public class ApiClient {
         return this;
     }
 
+    public List<ServerConfiguration> getServers() {
+        return servers;
+    }
+
+    public ApiClient setServers(List<ServerConfiguration> servers) {
+        this.servers = servers;
+        return this;
+    }
+
+    public Integer getServerIndex() {
+        return serverIndex;
+    }
+
+    public ApiClient setServerIndex(Integer serverIndex) {
+        this.serverIndex = serverIndex;
+        return this;
+    }
+
+    public Map<String, String> getServerVariables() {
+        return serverVariables;
+    }
+
+    public ApiClient setServerVariables(Map<String, String> serverVariables) {
+        this.serverVariables = serverVariables;
+        return this;
+    }
+
     /**
      * Get HTTP client
      *
@@ -1196,7 +1232,18 @@ public class ApiClient {
         if (baseUrl != null) {
             url.append(baseUrl).append(path);
         } else {
-            url.append(basePath).append(path);
+            String baseURL;
+            if (serverIndex != null) {
+                if (serverIndex < 0 || serverIndex >= servers.size()) {
+                    throw new ArrayIndexOutOfBoundsException(String.format(
+                    "Invalid index %d when selecting the host settings. Must be less than %d", serverIndex, servers.size()
+                    ));
+                }
+                baseURL = servers.get(serverIndex).URL(serverVariables);
+            } else {
+                baseURL = basePath;
+            }
+            url.append(baseURL).append(path);
         }
 
         if (queryParams != null && !queryParams.isEmpty()) {
diff --git a/samples/client/petstore/java/okhttp-gson-dynamicOperations/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/okhttp-gson-dynamicOperations/src/main/java/org/openapitools/client/ApiClient.java
index fc569591c37..8b5e7c1e39f 100644
--- a/samples/client/petstore/java/okhttp-gson-dynamicOperations/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/okhttp-gson-dynamicOperations/src/main/java/org/openapitools/client/ApiClient.java
@@ -72,6 +72,15 @@ import org.openapitools.client.auth.OAuthFlow;
 public class ApiClient {
 
     private String basePath = "http://petstore.swagger.io:80/v2";
+    protected List<ServerConfiguration> servers = new ArrayList<ServerConfiguration>(Arrays.asList(
+    new ServerConfiguration(
+      "http://petstore.swagger.io:80/v2",
+      "No description provided",
+      new HashMap<String, ServerVariable>()
+    )
+  ));
+    protected Integer serverIndex = 0;
+    protected Map<String, String> serverVariables = null;
     private boolean debugging = false;
     private Map<String, String> defaultHeaderMap = new HashMap<String, String>();
     private Map<String, String> defaultCookieMap = new HashMap<String, String>();
@@ -247,6 +256,33 @@ public class ApiClient {
         return this;
     }
 
+    public List<ServerConfiguration> getServers() {
+        return servers;
+    }
+
+    public ApiClient setServers(List<ServerConfiguration> servers) {
+        this.servers = servers;
+        return this;
+    }
+
+    public Integer getServerIndex() {
+        return serverIndex;
+    }
+
+    public ApiClient setServerIndex(Integer serverIndex) {
+        this.serverIndex = serverIndex;
+        return this;
+    }
+
+    public Map<String, String> getServerVariables() {
+        return serverVariables;
+    }
+
+    public ApiClient setServerVariables(Map<String, String> serverVariables) {
+        this.serverVariables = serverVariables;
+        return this;
+    }
+
     /**
      * Get HTTP client
      *
@@ -1274,7 +1310,18 @@ public class ApiClient {
         if (baseUrl != null) {
             url.append(baseUrl).append(path);
         } else {
-            url.append(basePath).append(path);
+            String baseURL;
+            if (serverIndex != null) {
+                if (serverIndex < 0 || serverIndex >= servers.size()) {
+                    throw new ArrayIndexOutOfBoundsException(String.format(
+                    "Invalid index %d when selecting the host settings. Must be less than %d", serverIndex, servers.size()
+                    ));
+                }
+                baseURL = servers.get(serverIndex).URL(serverVariables);
+            } else {
+                baseURL = basePath;
+            }
+            url.append(baseURL).append(path);
         }
 
         if (queryParams != null && !queryParams.isEmpty()) {
diff --git a/samples/client/petstore/java/okhttp-gson-group-parameter/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/okhttp-gson-group-parameter/src/main/java/org/openapitools/client/ApiClient.java
index d9e3fe85b09..221fccee4f6 100644
--- a/samples/client/petstore/java/okhttp-gson-group-parameter/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/okhttp-gson-group-parameter/src/main/java/org/openapitools/client/ApiClient.java
@@ -66,6 +66,15 @@ import org.openapitools.client.auth.OAuthFlow;
 public class ApiClient {
 
     private String basePath = "http://petstore.swagger.io/v2";
+    protected List<ServerConfiguration> servers = new ArrayList<ServerConfiguration>(Arrays.asList(
+    new ServerConfiguration(
+      "http://petstore.swagger.io/v2",
+      "No description provided",
+      new HashMap<String, ServerVariable>()
+    )
+  ));
+    protected Integer serverIndex = 0;
+    protected Map<String, String> serverVariables = null;
     private boolean debugging = false;
     private Map<String, String> defaultHeaderMap = new HashMap<String, String>();
     private Map<String, String> defaultCookieMap = new HashMap<String, String>();
@@ -230,6 +239,33 @@ public class ApiClient {
         return this;
     }
 
+    public List<ServerConfiguration> getServers() {
+        return servers;
+    }
+
+    public ApiClient setServers(List<ServerConfiguration> servers) {
+        this.servers = servers;
+        return this;
+    }
+
+    public Integer getServerIndex() {
+        return serverIndex;
+    }
+
+    public ApiClient setServerIndex(Integer serverIndex) {
+        this.serverIndex = serverIndex;
+        return this;
+    }
+
+    public Map<String, String> getServerVariables() {
+        return serverVariables;
+    }
+
+    public ApiClient setServerVariables(Map<String, String> serverVariables) {
+        this.serverVariables = serverVariables;
+        return this;
+    }
+
     /**
      * Get HTTP client
      *
@@ -1269,7 +1305,18 @@ public class ApiClient {
         if (baseUrl != null) {
             url.append(baseUrl).append(path);
         } else {
-            url.append(basePath).append(path);
+            String baseURL;
+            if (serverIndex != null) {
+                if (serverIndex < 0 || serverIndex >= servers.size()) {
+                    throw new ArrayIndexOutOfBoundsException(String.format(
+                    "Invalid index %d when selecting the host settings. Must be less than %d", serverIndex, servers.size()
+                    ));
+                }
+                baseURL = servers.get(serverIndex).URL(serverVariables);
+            } else {
+                baseURL = basePath;
+            }
+            url.append(baseURL).append(path);
         }
 
         if (queryParams != null && !queryParams.isEmpty()) {
diff --git a/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/org/openapitools/client/ApiClient.java
index 04bb97a8dbe..cbde9972bb3 100644
--- a/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/okhttp-gson-parcelableModel/src/main/java/org/openapitools/client/ApiClient.java
@@ -66,6 +66,15 @@ import org.openapitools.client.auth.OAuthFlow;
 public class ApiClient {
 
     private String basePath = "http://petstore.swagger.io:80/v2";
+    protected List<ServerConfiguration> servers = new ArrayList<ServerConfiguration>(Arrays.asList(
+    new ServerConfiguration(
+      "http://petstore.swagger.io:80/v2",
+      "No description provided",
+      new HashMap<String, ServerVariable>()
+    )
+  ));
+    protected Integer serverIndex = 0;
+    protected Map<String, String> serverVariables = null;
     private boolean debugging = false;
     private Map<String, String> defaultHeaderMap = new HashMap<String, String>();
     private Map<String, String> defaultCookieMap = new HashMap<String, String>();
@@ -236,6 +245,33 @@ public class ApiClient {
         return this;
     }
 
+    public List<ServerConfiguration> getServers() {
+        return servers;
+    }
+
+    public ApiClient setServers(List<ServerConfiguration> servers) {
+        this.servers = servers;
+        return this;
+    }
+
+    public Integer getServerIndex() {
+        return serverIndex;
+    }
+
+    public ApiClient setServerIndex(Integer serverIndex) {
+        this.serverIndex = serverIndex;
+        return this;
+    }
+
+    public Map<String, String> getServerVariables() {
+        return serverVariables;
+    }
+
+    public ApiClient setServerVariables(Map<String, String> serverVariables) {
+        this.serverVariables = serverVariables;
+        return this;
+    }
+
     /**
      * Get HTTP client
      *
@@ -1275,7 +1311,18 @@ public class ApiClient {
         if (baseUrl != null) {
             url.append(baseUrl).append(path);
         } else {
-            url.append(basePath).append(path);
+            String baseURL;
+            if (serverIndex != null) {
+                if (serverIndex < 0 || serverIndex >= servers.size()) {
+                    throw new ArrayIndexOutOfBoundsException(String.format(
+                    "Invalid index %d when selecting the host settings. Must be less than %d", serverIndex, servers.size()
+                    ));
+                }
+                baseURL = servers.get(serverIndex).URL(serverVariables);
+            } else {
+                baseURL = basePath;
+            }
+            url.append(baseURL).append(path);
         }
 
         if (queryParams != null && !queryParams.isEmpty()) {
diff --git a/samples/client/petstore/java/okhttp-gson-swagger1/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/okhttp-gson-swagger1/src/main/java/org/openapitools/client/ApiClient.java
index d9e3fe85b09..221fccee4f6 100644
--- a/samples/client/petstore/java/okhttp-gson-swagger1/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/okhttp-gson-swagger1/src/main/java/org/openapitools/client/ApiClient.java
@@ -66,6 +66,15 @@ import org.openapitools.client.auth.OAuthFlow;
 public class ApiClient {
 
     private String basePath = "http://petstore.swagger.io/v2";
+    protected List<ServerConfiguration> servers = new ArrayList<ServerConfiguration>(Arrays.asList(
+    new ServerConfiguration(
+      "http://petstore.swagger.io/v2",
+      "No description provided",
+      new HashMap<String, ServerVariable>()
+    )
+  ));
+    protected Integer serverIndex = 0;
+    protected Map<String, String> serverVariables = null;
     private boolean debugging = false;
     private Map<String, String> defaultHeaderMap = new HashMap<String, String>();
     private Map<String, String> defaultCookieMap = new HashMap<String, String>();
@@ -230,6 +239,33 @@ public class ApiClient {
         return this;
     }
 
+    public List<ServerConfiguration> getServers() {
+        return servers;
+    }
+
+    public ApiClient setServers(List<ServerConfiguration> servers) {
+        this.servers = servers;
+        return this;
+    }
+
+    public Integer getServerIndex() {
+        return serverIndex;
+    }
+
+    public ApiClient setServerIndex(Integer serverIndex) {
+        this.serverIndex = serverIndex;
+        return this;
+    }
+
+    public Map<String, String> getServerVariables() {
+        return serverVariables;
+    }
+
+    public ApiClient setServerVariables(Map<String, String> serverVariables) {
+        this.serverVariables = serverVariables;
+        return this;
+    }
+
     /**
      * Get HTTP client
      *
@@ -1269,7 +1305,18 @@ public class ApiClient {
         if (baseUrl != null) {
             url.append(baseUrl).append(path);
         } else {
-            url.append(basePath).append(path);
+            String baseURL;
+            if (serverIndex != null) {
+                if (serverIndex < 0 || serverIndex >= servers.size()) {
+                    throw new ArrayIndexOutOfBoundsException(String.format(
+                    "Invalid index %d when selecting the host settings. Must be less than %d", serverIndex, servers.size()
+                    ));
+                }
+                baseURL = servers.get(serverIndex).URL(serverVariables);
+            } else {
+                baseURL = basePath;
+            }
+            url.append(baseURL).append(path);
         }
 
         if (queryParams != null && !queryParams.isEmpty()) {
diff --git a/samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/ApiClient.java b/samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/ApiClient.java
index 8333bceafe2..1f87c42585d 100644
--- a/samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/ApiClient.java
+++ b/samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/ApiClient.java
@@ -66,6 +66,58 @@ import org.openapitools.client.auth.OAuthFlow;
 public class ApiClient {
 
     private String basePath = "http://petstore.swagger.io:80/v2";
+    protected List<ServerConfiguration> servers = new ArrayList<ServerConfiguration>(Arrays.asList(
+    new ServerConfiguration(
+      "http://{server}.swagger.io:{port}/v2",
+      "petstore server",
+      new HashMap<String, ServerVariable>() {{
+        put("server", new ServerVariable(
+          "No description provided",
+          "petstore",
+          new HashSet<String>(
+            Arrays.asList(
+              "petstore",
+              "qa-petstore",
+              "dev-petstore"
+            )
+          )
+        ));
+        put("port", new ServerVariable(
+          "No description provided",
+          "80",
+          new HashSet<String>(
+            Arrays.asList(
+              "80",
+              "8080"
+            )
+          )
+        ));
+      }}
+    ),
+    new ServerConfiguration(
+      "https://localhost:8080/{version}",
+      "The local server",
+      new HashMap<String, ServerVariable>() {{
+        put("version", new ServerVariable(
+          "No description provided",
+          "v2",
+          new HashSet<String>(
+            Arrays.asList(
+              "v1",
+              "v2"
+            )
+          )
+        ));
+      }}
+    ),
+    new ServerConfiguration(
+      "https://127.0.0.1/no_variable",
+      "The local server without variables",
+      new HashMap<String, ServerVariable>()
+    )
+  ));
+    protected Integer serverIndex = 0;
+    protected Map<String, String> serverVariables = null;
     private boolean debugging = false;
     private Map<String, String> defaultHeaderMap = new HashMap<String, String>();
     private Map<String, String> defaultCookieMap = new HashMap<String, String>();
@@ -242,6 +294,33 @@ public class ApiClient {
         return this;
     }
 
+    public List<ServerConfiguration> getServers() {
+        return servers;
+    }
+
+    public ApiClient setServers(List<ServerConfiguration> servers) {
+        this.servers = servers;
+        return this;
+    }
+
+    public Integer getServerIndex() {
+        return serverIndex;
+    }
+
+    public ApiClient setServerIndex(Integer serverIndex) {
+        this.serverIndex = serverIndex;
+        return this;
+    }
+
+    public Map<String, String> getServerVariables() {
+        return serverVariables;
+    }
+
+    public ApiClient setServerVariables(Map<String, String> serverVariables) {
+        this.serverVariables = serverVariables;
+        return this;
+    }
+
     /**
      * Get HTTP client
      *
@@ -1294,7 +1373,18 @@ public class ApiClient {
         if (baseUrl != null) {
             url.append(baseUrl).append(path);
         } else {
-            url.append(basePath).append(path);
+            String baseURL;
+            if (serverIndex != null) {
+                if (serverIndex < 0 || serverIndex >= servers.size()) {
+                    throw new ArrayIndexOutOfBoundsException(String.format(
+                    "Invalid index %d when selecting the host settings. Must be less than %d", serverIndex, servers.size()
+                    ));
+                }
+                baseURL = servers.get(serverIndex).URL(serverVariables);
+            } else {
+                baseURL = basePath;
+            }
+            url.append(baseURL).append(path);
         }
 
         if (queryParams != null && !queryParams.isEmpty()) {