001    /* Current.java --
002       Copyright (C) 2005 Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package org.omg.PortableInterceptor;
040    
041    import org.omg.CORBA.portable.IDLEntity;
042    
043    /**
044     * <p>
045     * The portable interceptor Current (PICurrent) contains multiple slots where an
046     * interceptor can rememeber the request - specific values between subsequent
047     * calls of the interceptor methods. In multithreaded environment, it is not
048     * possible just to store such data in the interceptor object fields.
049     * </p>
050     * <p>
051     * On the client side, it is possible to set the initial slot values by
052     * modifying slots on the Current, returend by ORB.resolve_initial_references
053     * ("PICurrent"). The returned value is narrowed with the
054     * {@link CurrentHelper#narrow}. On the subsequent invocation, made from the
055     * same thread, the interceptors will see the initial slot values as they were
056     * set using this approach.
057     * </p>
058     * <p>
059     * There are no way to set the initial values for the server side interceptors,
060     * the default values (Any with typecode TCKind.tk_null) should be always
061     * assumed.
062     * </p>
063     * <p>
064     * Since an Interceptor is running in a thread, it is running with a thread
065     * context and there is a PICurrent on that context. If the Interceptor calls
066     * ORB.resolve_initial_references ("PICurrent"), it gets the PICurrent within
067     * its thread scope. This PICurrent is different than the request scope
068     * PICurrent that the Interceptor obtains via calls to the Client- or Server-
069     * RequestInfo object.
070     * </p>
071     * <p>
072     * On the client side the PICurrent can be used to detect the recursive
073     * invocations, performed by interceptors. If one of the interceptors makes call
074     * via the same ORB, this call is then showed to all interceptors, including the
075     * interceptor that made it. To avoid infinite recursion, the during each call
076     * this interceptor can set some "recursion flag" into one of the slots of the
077     * PICurrent. If the flag is set on the entry point, this indicates a recursive
078     * call of that request.
079     * </p>
080     */
081    public interface Current extends CurrentOperations,
082      org.omg.CORBA.Current,
083      IDLEntity
084    {
085    }