幾つかのサーバエンジンプロパティの変更が必要な場合はよくあります。これらのプロパティを変更する方法は必要事項によって異なります。例えば，ポート番号を変更したい場合は，次のようにします。

• デフォルトのlistener.portプロパティを変更
• 新しいサーバエンジンを生成

デフォルトのlistener.portプロパティを変更することは最も単純な方法ですが，デフォルトのサーバエンジンを使用するすべてのPOAに影響を与えます。

特定のPOAのポート番号を変更したい場合は，新しいサーバエンジンを生成し，この新サーバエンジンのプロパティを定義し，さらにPOAの生成時に新サーバエンジンを参照する必要があります。「7.7.1　サーバエンジンプロパティの設定」ではサーバエンジンプロパティの更新方法を説明しました。次に示すコードの一部では，サーバエンジンのプロパティの定義方法とユーザ定義のサーバエンジンポリシーによるPOAの生成方法を示しています。

コードサンプル7-23　特定サーバエンジンによるPOAの生成（C++）

 
// static initialization
AccountRegistry AccountManagerImpl::_accounts;
int main(int argc, char* const* argv)
{
   try {
   // Initialize the orb
   CORBA::ORB_var orb = CORBA::ORB_init(argc, argv);
   // Get the property manager; notice the value returned
   // is not placed into a 'var' type.
   VISPropertyManager_ptr pm = orb->getPropertyManager();
   pm->addProperty("vbroker.se.mySe.host", "");
   pm->addProperty("vbroker.se.mySe.proxyHost", "");
   pm->addProperty("vbroker.se.mySe.scms", "scmlist");
   pm->addProperty("vbroker.se.mySe.scm.scmlist.manager
       .type", "Socket");
   pm->addProperty("vbroker.se.mySe.scm.scmlist.manager
       .connectionMax", 100UL);
   pm->addProperty("vbroker.se.mySe.scm.scmlist.manager
       .connectionMaxIdle", 300UL);
   pm->addProperty("vbroker.se.mySe.scm.scmlist.listener
       .type", "IIOP");
   pm->addProperty("vbroker.se.mySe.scm.scmlist.listener
       .port", 55000UL);
   pm->addProperty("vbroker.se.mySe.scm.scmlist.listener
       .proxyPort", 0UL);
   pm->addProperty("vbroker.se.mySe.scm.scmlist.dispatcher
       .type", "ThreadPool");
   pm->addProperty("vbroker.se.mySe.scm.scmlist.dispatcher
       .threadMax", 100UL);
   pm->addProperty("vbroker.se.mySe.scm.scmlist.dispatcher
       .threadMin", 5UL);
   pm->addProperty("vbroker.se.mySe.scm.scmlist.dispatcher
       .threadMaxIdle", 300UL);
   // Get a reference to the rootPOA
   CORBA::Object_var obj = 
       orb->resolve_initial_references("RootPOA");
   PortableServer::POA_var rootPOA = 
       PortableServer::POA::_narrow(obj);
   // Create the policies
   CORBA::Any_var seAny(new CORBA::Any);
   // The SERVER_ENGINE_POLICY_TYPE requires a sequence,
   // even if only one engine is being specified.
   CORBA::StringSequence_var engines = 
      new CORBA::StringSequence(1UL);
   engines->length(1UL);
   engines[0UL] = CORBA::string_dup("mySe");
   seAny <<= engines;
   CORBA::PolicyList_var policies = new CORBA::PolicyList(2UL);
   policies->length(2UL);
   policies[0UL] = orb->create_policy(
      PortableServerExt::SERVER_ENGINE_POLICY_TYPE, seAny);
      policies[1Ul] = rootPOA->create_lifespan_policy
         (PortableServer::PERSISTENT);
   // Create our POA with our policies
   PortableServer::POAManager_var manager = 
      rootPOA->the_POAManager();
   PortableServer::POA_var myPOA = rootPOA->create_POA(
         "bank_se_policy_poa", manager, policies);
 
   // Create the servant
   AccountManagerImpl* managerServant = 
         new AccountManagerImpl();
   // Activate the servant
   PortableServer::ObjectId_var oid = 
         PortableServer::string_to_ObjectId("BankManager");
   myPOA->activate_object_with_id(oid ,managerServant);
   // Obtain the reference
   CORBA::Object_var ref = 
            myPOA->servant_to_reference(managerServant);
   CORBA::String_var string_ref = 
            orb->object_to_string(ref.in());
   ofstream refFile("ref.dat");
   refFile << string_ref << endl;
   refFile.close();
   // Activate the POA manager
   manager->activate();
   // Wait for Incoming Requests
   cout << "AccountManager Server ready" << endl;
   orb->run();
   }
   catch(const CORBA::Exception& e) {
   cerr << e << endl;
   return (1);
   }
return (0);
}

コードサンプル7-24　特定サーバエンジンによるPOAの生成（Java）

 
// Server.java
import org.omg.PortableServer.*;
public class Server {
   public static void main(String[ ] args) {
      try {
      // Initialize the ORB.
      org.omg.CORBA.ORB orb =
                          org.omg.CORBA.ORB.init(args,null);
      // Get property manager
      com.inprise.vbroker.properties.PropertyManager pm =
           ((com.inprise.vbroker.orb.ORB)orb).
                                       getPropertyManager();
      pm.addProperty("vbroker.se.mySe.host", "");
      pm.addProperty("vbroker.se.mySe.proxyHost", "");
      pm.addProperty("vbroker.se.mySe.scms", "scmlist");
      pm.addProperty(
         "vbroker.se.mySe.scm.scmlist.manager.type",
         "Socket");
      pm.addProperty(
         "vbroker.se.mySe.scm.scmlist.manager.connectionMax",
          100);
      pm.addProperty(
         "vbroker.se.mySe.scm.scmlist.
          manager.connectionMaxIdle", 300);
      pm.addProperty(
        "vbroker.se.mySe.scm.scmlist.listener.giopVersion", "1.2");
      pm.addProperty(
        "vbroker.se.mySe.scm.scmlist.listener.type", "IIOP");
      pm.addProperty(
        "vbroker.se.mySe.scm.scmlist.listener.port", 55000);
      pm.addProperty(
        "vbroker.se.mySe.scm.scmlist.listener.proxyPort", 0);
      pm.addProperty(
         "vbroker.se.mySe.scm.scmlist.dispatcher.type",
         "ThreadPool");
      pm.addProperty(
         "vbroker.se.mySe.scm.scmlist.dispatcher.threadMax",
          100);
      pm.addProperty(
         "vbroker.se.mySe.scm.scmlist.dispatcher.threadMin",
          5);
      pm.addProperty(
         "vbroker.se.mySe.scm.scmlist.
          dispatcher.threadMaxIdle",300);
      // get a reference to the rootPOA
      POA rootPOA = POAHelper.narrow(
         orb.resolve_initial_references("RootPOA"));
      // Create our server engine policy
      org.omg.CORBA.Any seAny = orb.create_any();
      org.omg.CORBA.StringSequenceHelper.insert(
         seAny, new String[ ]{"mySe"});
      org.omg.CORBA.Policy sePolicy =
      orb.create_policy(
            com.inprise.vbroker.PortableServerExt.
            SERVER_ENGINE_POLICY_TYPE.value, seAny);
         // Create policies for our persistent POA
         org.omg.CORBA.Policy[ ] policies = {
         rootPOA.create_lifespan_policy(
             LifespanPolicyValue.PERSISTENT),sePolicy
      };
      // Create myPOA with the right policies
      POA myPOA = rootPOA.create_POA("bank_se_policy_poa",
            rootPOA.the_POAManager(),
            policies );
      // Create the servant
      AccountManagerImpl managerServant =
                                   new AccountManagerImpl();
      // Activate the servant
      myPOA.activate_object_with_id(
         "BankManager".getBytes(), managerServant);
      // Obtaining the reference
      org.omg.CORBA.Object ref = myPOA.servant_to_reference(
         managerServant);
      // Now write out the IOR
      try {
         java.io.PrintWriter pw =
               new java.io.PrintWriter(
                         new java.io.FileWriter("ior.dat"));
         pw.println(orb.object_to_string(ref));
         pw.close();
      } catch (java.io.IOException e ) {
         System.out.println(
                   "Error writing the IOR to file ior.dat");
         return;
      }
      // Activate the POA manager
      rootPOA.the_POAManager().activate();
      System.out.println(ref + "is ready.");
      // Wait for incoming requests
      orb.run();
      } catch (Exception e){
         e.printStackTrace();
      }
   }
}