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diff --git a/TAO/docs/releasenotes/OBV.html b/TAO/docs/releasenotes/OBV.html deleted file mode 100644 index b0d729c4179..00000000000 --- a/TAO/docs/releasenotes/OBV.html +++ /dev/null @@ -1,149 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN"> -<html> -<body text="#000000" bgcolor="#FFFFFF"> - - <head> - <title>Object-by-Value status</title> - <!-- $Id$ --> - </head> - - <body> - <center> - <h1><a name="orb"></a>Objects-by-Value</h1> - Point of contact: <a href="mailto: coryan@cs.wustl.edu">Carlos O'Ryan</a> - - <p>Last Update: $Date$</p> - </center> - - <p>Objects-by-Value (OBV) describes the new type, <CODE>valuetype</CODE>. - It is introduced in CORBA 2.3 - <br>(Core: - <a href="http://www.omg.org/docs/ptc/98-12-04.pdf">ptc/98-12-04.pdf - </a> Mapping to C++: - <a href="http://www.omg.org/docs/ptc/98-09-03.pdf">ptc/98-09-03.pdf</a>). - This first implementation was contributed from - <a href="mailto: kuepper2@uni-wuppertal.de">Torsten Kuepper</a>. - <CODDE>Valuetype</CODE>s are similar to IDL <CODE>struct</CODE>s extended with - these features: - <ul> - <li><p>Encapsulate state and operations with local implementation.</p> - </li> - - <li><p>Single inheritance from a <CODE>valuetype</CODE> and - multiple inheritance from abstract - <CODE>valuetype</CODE>s. Eventually support of an - interface.</p> - </li> - <li><p>References to other <CODE>valuetype</CODE>s, with the - possibility of NULL references or shared (aliased) references.</p> - </li> - </ul> - - <p><CODE>Valuetype</CODE>s will likely be used to implement - abstract datatypes (ADT)s that can be copied to another process. - All processes that use the <CODE>valuetype</CODE> must have an - implementation for it since CORBA does not support code - migration, a la Java RMI.</p> - - <a name="current"><h3>Current status:</h3></a> - - <ul> - <li><p>The IDL compiler understands <CODE>valuetype</CODE>, if - it was compiled with <CODE>IDL_HAS_VALUETYPE</CODE> - defined. New options of TAO's IDL are: <P> - <UL> - <LI>-Gv Enable OBV support - <LI>-Sv Disable OBV support (default) - <LI>-Wb,obv_opt_accessor Make accessor and modifier functions inline. - Overriding them is not allowed in this mode. - </UL> - <p><CODE>libTAO</CODE> must be compiled with <CODE>TAO_HAS_VALUETYPE</CODE>.</p> - </li> - <li><p><CODE>Valuetype</CODE>s can be used as arguments in CORBA invocations. - There is an example in - <A HREF="http://www.cs.wustl.edu/~schmidt/ACE_wrappers/TAO/examples/OBV/Typed_Events">$TAO_ROOT/TAO/examples/OBV/Typed_Events</A>. - <CODE>Valuetype</CODE>s could even reference other - <CODE>valuetype</CODE> objects (but without sharing). - </p> - </li> - </ul> - - <a name="issues"><h3>Known issues:</h3></a> - - <ul> - <li><p>No support for <code>TypeCodes</code> of - <code>valuetype</code> objects - </p> - </li> - - <li><p><CODE>Valuetype</CODE>s work only in conjunction with - compiled marshalling (<CODE>-Gc</CODE>, currently default for - <CODE>tao_idl</CODE>). - </p> - </li> - - <li><p>No support for <code>TypeCodes</code> of - <code>valuetype</code> objects. Hence moving it into an - <code>any</code> is not possible yet. - </p> - </li> - - <li><p><CODE>Valuetype</CODE>s can not be contained in other types like - <CODE>struct</CODE>, <CODE>union</CODE>, - <CODE>sequence</CODE> or <CODE>array</CODE>. - </p> - </li> - - <li><p>No support for sharing (aliasing). - </p> - </li> - - <li><p>Forward and typedef'd declaration does not work.</p> - </li> - - <li><p>Inheritance (support) from an ordinary interface - not implemented.</p> - </li> - - <li><p>No support for abstract interfaces. - </p> - </li> - - <li><p>No support for <CODE>valuebox</CODE>es - </p> - </li> - - <li><p>No support for fragmentation (chunking) of the marshalled - <CODE>valuetype</CODE> object. Hence no support for truncation or - custom marshalling.</p> - </li> - - <li><p>The marshal engine accesses the state members directly and - does not utilize the accessor/modifier functions. This not - like in the CORBA specs and needs a change. But the - optimized mode (<CODE>-Wb,obv_opt_accessor</CODE>) should be - unaffected of that. - </p> - </li> - - <li><p>Obtaining a repository id of a <CODE>valuetype</CODE> - is currently non-standard. Hashed repository ids are not - implemented. - </p> - </li> - - <li><p>The map of <CODE>valuetype</CODE> factories needs some - revision to provide proper locking. Currently the - registration of factories is best completed before - unmarshalling <CODE>valuetype</CODE>s. - There is one map of factories for the whole process. This - will once be changed to conform to the specs, which - suggests one per ORB. - </p> - </li> - </ul> - - <P><HR><P> - <a href="#toc">Back to TOC</a> - </body> -</html> |