jurt/com/sun/star/lib/uno/environments/remote/IProtocol.java

   1 /*
   2  * This file is part of the LibreOffice project.
   3  *
   4  * This Source Code Form is subject to the terms of the Mozilla Public
   5  * License, v. 2.0. If a copy of the MPL was not distributed with this
   6  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   7  *
   8  * This file incorporates work covered by the following license notice:
   9  *
  10  *   Licensed to the Apache Software Foundation (ASF) under one or more
  11  *   contributor license agreements. See the NOTICE file distributed
  12  *   with this work for additional information regarding copyright
  13  *   ownership. The ASF licenses this file to you under the Apache
  14  *   License, Version 2.0 (the "License"); you may not use this file
  15  *   except in compliance with the License. You may obtain a copy of
  16  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  17  */
  18
  19 package com.sun.star.lib.uno.environments.remote;
  20
  21 import com.sun.star.lib.uno.typedesc.TypeDescription;
  22 import java.io.IOException;
  23
  24 /**
  25  * An abstraction of remote bridge protocols.
  26  *
  27  * <p>A class implementing a given protocol <var>prot</var> must be named
  28  * <code>com.sun.star.lib.uno.protocols.<var>prot</var>.<var>prot</var></code>
  29  * and must have a public constructor that takes four arguments:  The first
  30  * argument of type <code>com.sun.star.uno.IBridge</code> must not be null.  The
  31  * second argument of type <code>String</code> represents any attributes; it may
  32  * be null if there are no attributes.  The third argument of type
  33  * <code>java.io.InputStream</code> must not be null.  The fourth argument of
  34  * type <code>java.io.OutputStream</code> must not be null.</p>
  35  */
  36 public interface IProtocol {
  37     /**
  38      * Initializes the connection.
  39      *
  40      * <p>This method must be called exactly once, after the
  41      * <code>readMessage</code> loop has already been established.</p>
  42      */
  43     void init() throws IOException;
  44
  45     void terminate();
  46
  47     /**
  48      * Reads a request or reply message.
  49      *
  50      * <p>Access to this method from multiple threads must be properly
  51      * synchronized.</p>
  52      *
  53      * @return a non-null message; if the input stream is exhausted, a
  54      *     <code>java.io.IOException</code> is thrown instead.
  55      */
  56     Message readMessage() throws IOException;
  57
  58     /**
  59      * Writes a request message.
  60      *
  61      * @param oid a non-null OID.
  62      * @param type a non-null UNO type.
  63      * @param function a non-null function (the name of a UNO interface method
  64      *     or attribute compatible with the given <code>type</code>, or either
  65      *     <code>"queryInterface"</code> or <code>"release"</code>).
  66      * @param tid a non-null TID.
  67      * @param arguments a list of UNO arguments compatible with the given
  68      *     <code>type</code> and <code>function</code>; may be null to represent
  69      *     an empty list.
  70      * @return <code>true</code> if the request message is sent as a synchronous
  71      *     request.
  72      */
  73     boolean writeRequest(
  74         String oid, TypeDescription type, String function, ThreadId tid,
  75         Object[] arguments)
  76         throws IOException;
  77
  78     /**
  79      * Writes a reply message.
  80      *
  81      * @param exception <code>true</code> if the reply corresponds to a raised
  82      *     exception.
  83      * @param tid a non-null TID.
  84      * @param result if <code>exception</code> is <code>true</code>, a non-null
  85      *     UNO exception; otherwise, a UNO return value, which may be null to
  86      *     represent a <code>VOID</code> return value.
  87      */
  88     void writeReply(boolean exception, ThreadId tid, Object result)
  89         throws IOException;
  90 }