connectivity/source/inc/java/LocalRef.hxx

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  19
  20 #ifndef INCLUDED_CONNECTIVITY_SOURCE_INC_JAVA_LOCALREF_HXX
  21 #define INCLUDED_CONNECTIVITY_SOURCE_INC_JAVA_LOCALREF_HXX
  22
  23 #include <jvmaccess/virtualmachine.hxx>
  24
  25
  26 namespace connectivity { namespace jdbc
  27 {
  28
  29     /** helper class to hold a local ref to a JNI object
  30
  31         Note that this class never actually calls NewLocalRef. It is assumed that all objects
  32         passed are already acquired with a local ref (as it usually is the case if you obtain
  33         the object from an JNI method).
  34     */
  35     template< typename T >
  36     class LocalRef
  37     {
  38     public:
  39         explicit LocalRef( JNIEnv& environment )
  40             :m_environment( environment )
  41             ,m_object( NULL )
  42         {
  43         }
  44
  45         LocalRef( JNIEnv& environment, T object )
  46             :m_environment( environment )
  47             ,m_object( object )
  48         {
  49         }
  50
  51         ~LocalRef()
  52         {
  53             reset();
  54         }
  55
  56         T release()
  57         {
  58             T t = m_object;
  59             m_object = NULL;
  60             return t;
  61         }
  62
  63         void set( T object ) { reset(); m_object = object; }
  64
  65         void reset()
  66         {
  67             if ( m_object != NULL )
  68             {
  69                 m_environment.DeleteLocalRef( m_object );
  70                 m_object = NULL;
  71             }
  72         }
  73
  74         JNIEnv& env() const { return m_environment; }
  75         T       get() const { return m_object; }
  76         bool    is()  const { return m_object != NULL; }
  77
  78     private:
  79         LocalRef(LocalRef &) SAL_DELETED_FUNCTION;
  80         void operator =(LocalRef &) SAL_DELETED_FUNCTION;
  81
  82     protected:
  83         JNIEnv& m_environment;
  84         T       m_object;
  85     };
  86
  87
  88 } } // namespace connectivity::jdbc
  89
  90
  91 #endif // INCLUDED_CONNECTIVITY_SOURCE_INC_JAVA_LOCALREF_HXX
  92
  93 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */