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diff --git a/TAO/docs/tutorials/Quoter/Simple/Impl-Repo/index.html b/TAO/docs/tutorials/Quoter/Simple/Impl-Repo/index.html new file mode 100644 index 00000000000..df534fe1a6e --- /dev/null +++ b/TAO/docs/tutorials/Quoter/Simple/Impl-Repo/index.html @@ -0,0 +1,177 @@ +<!Doctype HTML PUBLIC "-//IETF//DTD HTML//EN"> +<html> + <head> + <title>Implementation Repository</title> + <!-- $Id$ --> + </head> + + <body text = "#000000" + link="#000fff" + vlink="#ffofof" + bgcolor="#ffffff"> + + <h3>Implementation Repository</h3> + <P> In the previous example, the client must contact the server + at least once. If the server has been moved to a different host or + port, or if the server is down, binding between the client and + the server fails. Indirect binding through an external location + broker like the Implementation Repository solves this problem. + </P> + <P>An implementation repository maintains a data structure known + as a server table to keep track of the servers. It maintains a + registry of known servers, records which server is currently + running on which host and at which port number, and starts + servers on demand if they are registered to do so. + </P> + <P> When a server + creates a persistent reference, it sets the address and port + number in the profile body of the IOR to point at the + implementation repository that is responsible for the server. + When a client uses this IOR, it gets connected to the + implementation repository, provided the implementation + repository is not down. The repository decodes this IOR and uses + the POA name from the object key to index into its server + table. The repository replies with the current addressing + information of the actual server. The client now sends the + request to the actual server. + </P> + <P>In this example, let's proceed to modify our previous stock + factory example to support indirect binding through an + implementation repository. + </P> + <P>The only thing we have to do for this is to register our + childPOA with the implementation repository. + </P> + <PRE> + orb->_tao_add_to_IOR_table ("childPOA", stock_factory.in ()); + </PRE> + <P> Then, we stringify all the object references as usual and + print them out. + </P> + <PRE> + CORBA::String_var ior = orb->object_to_string (stock_factory.in ()); + </PRE> + <H3>Exercise</H3> + Modify the <a href=../Server/server.cpp>server.cpp</a> in the simple + server to create the persistent child POA. + You can use the same + <a href=../Quoter.idl>Quoter.idl</a> + <a href=../Server/Stock_i.h>Stock_i.h</a> + <a href=../Server/Stock_i.cpp>Stock_i.cpp</a> + <a href=../Server/Stock_Factory_i.h>Stock_Factory_i.h</a> + <a href=../Server/Stock_Factory_i.cpp>Stock_Factory_i.cpp</a> + <a href=../Client/client.cpp>Client.cpp</a> + You can use this <a href=GNUmakefile.Quoter_Simple_Impl_Repo_Server>Makefile</a>. + <H3>Solution</H3> + Compare your server.cpp with <a href = server.cpp>server.cpp</a> file. + + <H3>Testing</H3> + <P>To test your changes, you need to run four programs. The first + step is to start up the Implementation Repository provided + with TAO. The Implementation Repository is split into one locator at least + one activator. The locator provides the interface visible + to the application intending to use the repository (in our case, + the client), while the activators do the real work of activating + and maintaining servers. + </P> + + <P>First, we start the locator. We need to dump the IOR of the ImplRepo_Service to a file, + so that both the activator and the client can find the locator. + </P> + <PRE> + $ $TAO_ROOT/orbsvcs/ImplRepo_Service/ImplRepo_Service -o implrepo.ior -d 0 -ORBobjrefstyle URL & + </PRE> + + <P>Second, we start the activator, pointing it to the locator's IOR file. + </P> + <PRE> + $ $TAO_ROOT/orbsvcs/ImplRepo_Service/ImR_Activator -ORBInitRef ImplRepoService=file://implrepo.ior + + ImR Activator: Starting doc.ece.uci.edu + ImR Activator: Registered with ImR. + </PRE> + + <P> Next, we need to register our server with the implementation + repository. We can use the + <CODE>$TAO_ROOT/orbsvcs/ImplRepo_Service/tao_imr</CODE> + application provided with TAO to add our server to the server + database in the implementation repository. + </P> + <PRE> + $ $TAO_ROOT/orbsvcs/ImplRepo_Service/tao_imr -ORBInitRef + ImplRepoService=file://implrepo.ior add childPOA -c + "./server -ORBUseIMR 1 -ORBobjrefstyle URL -ORBInitRef + ImplRepoService=file://implrepo.ior" + + Successfully registered server <childPOA> + </PRE> + <p> On Windows platforms, use this command instead to register the server + in the implementation repository + </p> + <PRE> + $ACE_ROOT/bin/tao_imr -ORBInitRef ImplRepoService=file://implrepo.ior + add childPOA -c "./server -ORBUseIMR 1 -ORBobjrefstyle URL + -ORBInitRef ImplRepoService=file://implrepo.ior" + </PRE> + <P> We specify the <CODE>-ORBInitRef</CODE> option to use the IOR in + the <CODE>implrepo.ior</CODE> file and the <CODE>-ORBUseIMR</CODE> + option to tell the server to use the IMR for notification of its + startup and shutdown. + </P> + <P>The next step is to generate a simple IOR for our server + to be used with the IMR, using the + <CODE>ior</CODE> option, and write it to <CODE>stock_factory.ior</CODE>. + + </P> + <PRE> + $tao_imr -ORBInitRef ImplRepoService=file://implrepo.ior ior + childPOA -f stock_factory.ior + + corbaloc:iiop:1.1@doc.ece.uci.edu:2690/childPOA + </PRE> + <P> From now, the implementation repository is all set to keep + track of our server and do the needful on a method invocation + on our server. + </P> + <P> Now, execute the client as usual. + </P> + <PRE> + ./client file://stock_factory.ior MSFT RHAT + + The price of a stock in "Microsoft, Inc." is $91 + The price of a stock in "RedHat, Inc." is $210 + </PRE> + <P> For testing the persistency of the POA, let's shut down the + server and then run the client. + </P> + <PRE> + $tao_imr -ORBInitRef ImplRepoService=file://implrepo.ior + shutdown childPOA + + Successfully shutdown server <childPOA> + + ./client file://stock_factory.ior MSFT RHAT + + The price of a stock in "RedHat, Inc." is $210 + The price of a stock in "Microsoft, Inc." is $91 + </PRE> + <H3>More Reading</H3> + <P>More information on Implementation Repository is + <A HREF="../../../../../docs/implrepo/index.html">here</A>. + </P> + <P>The <A HREF="http://www.triodia.com/staff/michi-henning.html">Henning</A> and <A HREF="http://www.iona.com/hyplan/vinoski/">Vinoski</A> + <A HREF="http://www.iona.com/hyplan/vinoski/#book">CORBA book</A> discusses POA policies in detail. Likewise, + the Schmidt and Vinoski + <A HREF="http://www.cs.wustl.edu/~schmidt/report-doc.html">columns</A> in C++ Report also include several articles about the POA. Finally, + the <A HREF="http://www.cs.wustl.edu/~schmidt/TAO.html">TAO</A> + distribution includes <A HREF="../../../../../examples/POA">examples</A> that illustrate how + to use the POA policies. + </P> + <hr> + <address><a href="mailto:pgontla@ece.uci.edu">Priyanka Gontla</a></address> +<!-- Created: Wed Mar 29 17:35:30 PST 2000 --> +<!-- hhmts start --> +Last modified: Sat May 19 17:19:07 CDT 2001 +<!-- hhmts end --> + </body> +</html> |