tnameserv(1)						      General Commands Manual						      tnameserv(1)

NAME

       tnameserv - Java IDL name server starter script

SYNOPSIS

       tnameserv -ORBInitialPort portNumber

DESCRIPTION

       The  CORBA COS (Common Object Services) Naming Service provides a tree-like directory for object references much like a filesystem provides
       a directory structure for files.  The Naming Service provided with Java IDL is a simple implementation of the COS Naming Service specifica-
       tion.

       Object  references  are stored in the namespace by name and each object reference-name pair is called a name binding.  Name bindings may be
       organized under naming contexts.  Naming contexts are themselves name bindings and serve the same organizational function as a file  system
       subdirectory.   All bindings are stored under the initial naming context.  The initial naming context is the only persistent binding in the
       namespace; the rest of the namespace is lost if the Java IDL name server process halts and restarts.

       For an applet or application to use COS naming, its ORB must know the name and port of a host running a naming service or have access to  a
       stringified  initial naming context for that name server.  The naming service can either be the Java IDL name server or another COS-compli-
       ant name service.

USAGE

   Starting the Java IDL Name Server
       You must start the Java IDL name server before an application or applet that uses its naming service.  Installation of the Java IDL product
       creates a script named tnameserv that starts the Java IDL name server.  Start the name server so it runs in the background.

       If  you	do  not  specify  otherwise,  the  Java  IDL  name server listens on port 900 for the bootstrap protocol used to implement the ORB
       resolve_initial_references() and list_initial_references() methods.  Specify a different port, for example, 1050, as follows:

	      example% tnameserv -ORBInitialPort 1050

       Clients of the name server must be made aware of the new port number.  Do this by setting the org.omg.CORBA.ORBInitialPort property to  the
       new port number when creating the ORB object.

   Stopping the Java IDL Name Server
       To stop the Java IDL name server, use the relevant operating system command, such as kill(1).  Note that names registered with the Java IDL
       name service disappear when the server is terminated.

   Sample Client: Adding Objects
       The following sample program illustrates how to add names to the namespace.  It is a self-contained Name Server	client	that  creates  the
       following simple tree.

	       Initial
	    Naming Context
	      /      
	     /	      
	  plans      personal
		       /
		      /  
	       calendar   schedule

       In  this  example,  "plans"  is	an object reference and "personal" is a naming context that contains two object references: "calendar" and
       "schedule".

       import java.util.Properties;
       import org.omg.CORBA.*;
       import org.omg.CosNaming.*;

       public class NameClient
       {
	  public static void main(String args[])
	  {
	     try {

       In the above section, Starting the Java IDL Name Server, the nameserver was started on port 1050.  The  following  code	ensures  that  the
       client program is aware of this port number.

	       Properties props = new Properties();
	       props.put("org.omg.CORBA.ORBInitialPort", "1050");
	       ORB orb = ORB.init(args, props);

       The  following  code  obtains  the initial naming context and assigns it to ctx.  The second line copies ctx into a dummy object reference,
       objref, that we will attach to various names and add into the namespace.

	       NamingContext ctx = NamingContextHelper.narrow
		   (orb.resolve_initial_references("NameService"));
	       NamingContext objref = ctx;

       The following code creates a name "plans" of type "text" and binds it to our dummy object reference.  "plans" is then added under the  ini-
       tial  naming  context  using rebind.  The rebind method allows us to run this program over and over again without getting the exceptions we
       would get from using bind.

	       NameComponent nc1 = new NameComponent("plans", "text");
	       NameComponent[] name1 = {nc1};
	       ctx.rebind(name1, objref);
	       System.out.println("plans rebind sucessful!");

       The following code creates a naming context called "Personal" of type "directory".  The resulting object reference, ctx2, is bound  to  the
       name and added under the initial naming context.

	       NameComponent nc2 = new NameComponent("Personal", "directory");
	       NameComponent[] name2 = {nc2};
	       NamingContext ctx2 = ctx.bind_new_context(name2);
	       System.out.println("new naming context added..");

       The  remainder  of  the code binds the dummy object reference using the names "schedule" and "calendar" under the "Personal" naming context
       (ctx2).

	       NameComponent nc3 = new NameComponent("schedule", "text");
	       NameComponent[] name3 = {nc3};
	       ctx2.rebind(name3, objref);
	       System.out.println("schedule rebind sucessful!");

	       NameComponent nc4 = new NameComponent("calender", "text");
	       NameComponent[] name4 = {nc4};
	       ctx2.rebind(name4, objref);
	       System.out.println("calender rebind sucessful!");

	   } catch (Exception e) {
	       e.printStackTrace(System.err);
	   }
	 }
       }

   Sample Client: Browsing the Namespace
       The following sample program illustrates how to browse the namespace.

       import java.util.Properties;
       import org.omg.CORBA.*;
       import org.omg.CosNaming.*;

       public class NameClientList
       {
	  public static void main(String args[])
	  {
	     try {

       In the above section, Starting the Java IDL Name Server, the nameserver was started on port 1050.  The  following  code	ensures  that  the
       client program is aware of this port number.

	       Properties props = new Properties();
	       props.put("org.omg.CORBA.ORBInitialPort", "1050");
	       ORB orb = ORB.init(args, props);

       The following code obtains the initial naming context.

	       NamingContext nc = NamingContextHelper.narrow
		  (orb.resolve_initial_references("NameService"));

       The  list  method  lists  the  bindings	in  the naming context.  In this case, up to 1000 bindings from the initial naming context will be
       returned in the BindingListHolder; any remaining bindings are returned in the BindingIteratorHolder.

	       BindingListHolder bl = new BindingListHolder();
	       BindingIteratorHolder blIt= new BindingIteratorHolder();
	       nc.list(1000, bl, blIt);

       The following code gets the array of bindings out of the returned BindingListHolder.  If there are no bindings, the program ends.

	       Binding bindings[] = bl.value;
	       if (bindings.length == 0) return;

       The remainder of the code loops through the bindings and prints the names out.

	       for (int i=0; i < bindings.length; i++) {

		   // get the object reference for each binding
		   org.omg.CORBA.Object obj = nc.resolve
			    (bindings[i].binding_name);
		   String objStr = orb.object_to_string(obj);
		   int lastIx = bindings[i].binding_name.length-1;

		   // check to see if this is a naming context
		   if (bindings[i].binding_type == BindingType.ncontext) {
		     System.out.println
			    ("Context: " + bindings[i].binding_name[lastIx].id);
		   } else {
		       System.out.println
			      ("Object: " + bindings[i].binding_name[lastIx].id);
		   }
	       }

	      } catch (Exception e) {
	       e.printStackTrace(System.err);
	      }
	  }
       }

SEE ALSO

       kill(1)

								   13 June 2000 						      tnameserv(1)