include/comphelper/componentbase.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
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   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #ifndef INCLUDED_COMPHELPER_COMPONENTBASE_HXX
  21 #define INCLUDED_COMPHELPER_COMPONENTBASE_HXX
  22
  23 #include <comphelper/comphelperdllapi.h>
  24 #include <cppuhelper/interfacecontainer.hxx>
  25
  26
  27 namespace comphelper
  28 {
  29
  30
  31     //= ComponentBase
  32
  33     class COMPHELPER_DLLPUBLIC ComponentBase
  34     {
  35     protected:
  36         /** creates a ComponentBase instance
  37
  38             The instance is not initialized. As a consequence, every ComponentMethodGuard instantiated for
  39             this component will throw a css::lang::NotInitializedException,
  40             until ->setInitialized() is called.
  41         */
  42         ComponentBase( ::cppu::OBroadcastHelper& _rBHelper )
  43             :m_rBHelper( _rBHelper )
  44             ,m_bInitialized( false )
  45         {
  46         }
  47
  48         struct NoInitializationNeeded { };
  49
  50         /** creates a ComponentBase instance
  51
  52             The instance is already initialized, so there's no need to call setInitialized later on. Use this
  53             constructor for component implementations which do not require explicit initialization.
  54         */
  55         ComponentBase( ::cppu::OBroadcastHelper& _rBHelper, NoInitializationNeeded )
  56             :m_rBHelper( _rBHelper )
  57             ,m_bInitialized( true )
  58         {
  59         }
  60
  61         ~ComponentBase() {}
  62
  63         /** marks the instance as initialized
  64
  65             Subsequent instantiations of a ComponentMethodGuard won't throw the NotInitializedException now.
  66         */
  67         void setInitialized()    { m_bInitialized = true; }
  68
  69     public:
  70         /// helper struct to grant access to selected public methods to the ComponentMethodGuard class
  71         struct GuardAccess { friend class ComponentMethodGuard; private: GuardAccess() { } };
  72
  73         /// retrieves the component's mutex
  74         ::osl::Mutex&   getMutex( GuardAccess )                 { return getMutex(); }
  75         /// checks whether the component is already disposed, throws a DisposedException if so.
  76         void                    checkDisposed( GuardAccess ) const;
  77         /// checks whether the component is already initialized, throws a NotInitializedException if not.
  78         void                    checkInitialized( GuardAccess ) const;
  79
  80     protected:
  81         /// retrieves the component's broadcast helper
  82         ::cppu::OBroadcastHelper&   getBroadcastHelper()    { return m_rBHelper; }
  83         /// retrieves the component's mutex
  84         ::osl::Mutex&               getMutex()              { return m_rBHelper.rMutex; }
  85         /// determines whether the instance is already disposed
  86         bool                        impl_isDisposed() const { return m_rBHelper.bDisposed; }
  87
  88         /// determines whether the component is already initialized
  89         bool
  90                 impl_isInitialized_nothrow() const { return m_bInitialized; }
  91
  92         /** returns the context to be used when throwing exceptions
  93
  94             The default implementation returns <NULL/>.
  95         */
  96         static css::uno::Reference< css::uno::XInterface >
  97                 getComponent();
  98
  99     private:
 100         ::cppu::OBroadcastHelper&   m_rBHelper;
 101         bool                        m_bInitialized;
 102     };
 103
 104     class ComponentMethodGuard
 105     {
 106     public:
 107         enum class MethodType
 108         {
 109             /// allow the method to be called only when being initialized and not being disposed
 110             Default,
 111             /// allow the method to be called without being initialized
 112             WithoutInit
 113
 114         };
 115
 116         ComponentMethodGuard( ComponentBase& _rComponent, const MethodType _eType = MethodType::Default )
 117             :m_aMutexGuard( _rComponent.getMutex( ComponentBase::GuardAccess() ) )
 118         {
 119             if ( _eType != MethodType::WithoutInit )
 120                 _rComponent.checkInitialized( ComponentBase::GuardAccess() );
 121             _rComponent.checkDisposed( ComponentBase::GuardAccess() );
 122         }
 123
 124         void clear()
 125         {
 126             m_aMutexGuard.clear();
 127         }
 128
 129     private:
 130         ::osl::ResettableMutexGuard   m_aMutexGuard;
 131     };
 132
 133
 134 } // namespace ComponentBase
 135
 136
 137 #endif // INCLUDED_COMPHELPER_COMPONENTBASE_HXX
 138
 139 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */