/*
* Copyright (c) 1996, 1999, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package org.omg.CORBA;
/**
* An object containing the information necessary for
* invoking a method. This class is
* the cornerstone of the ORB Dynamic
* Invocation Interface (DII), which allows dynamic creation and
* invocation of requests.
* A server cannot tell the difference between a client
* invocation using a client stub and a request using the DII.
* <P>
* A <code>Request</code> object consists of:
* <UL>
* <LI>the name of the operation to be invoked
* <LI>an <code>NVList</code> containing arguments for the operation.<BR>
* Each item in the list is a <code>NamedValue</code> object, which has three
* parts:
* <OL>
* <LI>the name of the argument
* <LI>the value of the argument (as an <code>Any</code> object)
* <LI>the argument mode flag indicating whether the argument is
* for input, output, or both
* </OL>
* </UL>
* <P>
* <code>Request</code> objects may also contain additional information,
* depending on how an operation was defined in the original IDL
* interface definition. For example, where appropriate, they may contain
* a <code>NamedValue</code> object to hold the return value or exception,
* a context, a list of possible exceptions, and a list of
* context strings that need to be resolved.
* <P>
* New <code>Request</code> objects are created using one of the
* <code>create_request</code> methods in the <code>Object</code> class.
* In other words, a <code>create_request</code> method is performed on the
* object which is to be invoked.
*
* @see org.omg.CORBA.NamedValue
*
*/
public abstract class Request {
/**
* Retrieves the the target object reference.
*
* @return the object reference that points to the
* object implementation for the method
* to be invoked
*/
public abstract org.omg.CORBA.Object target();
/**
* Retrieves the name of the method to be invoked.
*
* @return the name of the method to be invoked
*/
public abstract String operation();
/**
* Retrieves the <code>NVList</code> object containing the arguments
* to the method being invoked. The elements in the list are
* <code>NamedValue</code> objects, with each one describing an argument
* to the method.
*
* @return the <code>NVList</code> object containing the arguments
* for the method
*
*/
public abstract NVList arguments();
/**
* Retrieves the <code>NamedValue</code> object containing the return
* value for the method.
*
* @return the <code>NamedValue</code> object containing the result
* of the method
*/
public abstract NamedValue result();
/**
* Retrieves the <code>Environment</code> object for this request.
* It contains the exception that the method being invoked has
* thrown (after the invocation returns).
*
*
* @return the <code>Environment</code> object for this request
*/
public abstract Environment env();
/**
* Retrieves the <code>ExceptionList</code> object for this request.
* This list contains <code>TypeCode</code> objects describing the
* exceptions that may be thrown by the method being invoked.
*
* @return the <code>ExceptionList</code> object describing the exceptions
* that may be thrown by the method being invoked
*/
public abstract ExceptionList exceptions();
/**
* Retrieves the <code>ContextList</code> object for this request.
* This list contains context <code>String</code>s that need to
* be resolved and sent with the invocation.
*
*
* @return the list of context strings whose values
* need to be resolved and sent with the
* invocation.
*/
public abstract ContextList contexts();
/**
* Retrieves the <code>Context</code> object for this request.
* This is a list of properties giving information about the
* client, the environment, or the circumstances of this request.
*
* @return the <code>Context</code> object that is to be used
* to resolve any context strings whose
* values need to be sent with the invocation
*/
public abstract Context ctx();
/**
* Sets this request's <code>Context</code> object to the one given.
*
* @param c the new <code>Context</code> object to be used for
* resolving context strings
*/
public abstract void ctx(Context c);
/**
* Creates an input argument and adds it to this <code>Request</code>
* object.
*
* @return an <code>Any</code> object that contains the
* value and typecode for the input argument added
*/
public abstract Any add_in_arg();
/**
* Creates an input argument with the given name and adds it to
* this <code>Request</code> object.
*
* @param name the name of the argument being added
* @return an <code>Any</code> object that contains the
* value and typecode for the input argument added
*/
public abstract Any add_named_in_arg(String name);
/**
* Adds an input/output argument to this <code>Request</code> object.
*
* @return an <code>Any</code> object that contains the
* value and typecode for the input/output argument added
*/
public abstract Any add_inout_arg();
/**
* Adds an input/output argument with the given name to this
* <code>Request</code> object.
*
* @param name the name of the argument being added
* @return an <code>Any</code> object that contains the
* value and typecode for the input/output argument added
*/
public abstract Any add_named_inout_arg(String name);
/**
* Adds an output argument to this <code>Request</code> object.
*
* @return an <code>Any</code> object that contains the
* value and typecode for the output argument added
*/
public abstract Any add_out_arg();
/**
* Adds an output argument with the given name to this
* <code>Request</code> object.
*
* @param name the name of the argument being added
* @return an <code>Any</code> object that contains the
* value and typecode for the output argument added
*/
public abstract Any add_named_out_arg(String name);
/**
* Sets the typecode for the return
* value of the method.
*
* @param tc the <code>TypeCode</code> object containing type information
* for the return value
*/
public abstract void set_return_type(TypeCode tc);
/**
* Returns the <code>Any</code> object that contains the value for the
* result of the method.
*
* @return an <code>Any</code> object containing the value and
* typecode for the return value
*/
public abstract Any return_value();
/**
* Makes a synchronous invocation using the
* information in the <code>Request</code> object. Exception information is
* placed into the <code>Request</code> object's environment object.
*/
public abstract void invoke();
/**
* Makes a oneway invocation on the
* request. In other words, it does not expect or wait for a
* response. Note that this can be used even if the operation was
* not declared as oneway in the IDL declaration. No response or
* exception information is returned.
*/
public abstract void send_oneway();
/**
* Makes an asynchronous invocation on
* the request. In other words, it does not wait for a response before it
* returns to the user. The user can then later use the methods
* <code>poll_response</code> and <code>get_response</code> to get
* the result or exception information for the invocation.
*/
public abstract void send_deferred();
/**
* Allows the user to determine
* whether a response has been received for the invocation triggered
* earlier with the <code>send_deferred</code> method.
*
* @return <code>true</code> if the method response has
* been received; <code>false</code> otherwise
*/
public abstract boolean poll_response();
/**
* Allows the user to access the
* response for the invocation triggered earlier with the
* <code>send_deferred</code> method.
*
* @exception WrongTransaction if the method <code>get_response</code> was invoked
* from a different transaction's scope than the one from which the
* request was originally sent. See the OMG Transaction Service specification
* for details.
*/
public abstract void get_response() throws WrongTransaction;
};