root/lang/vb2005/FuwaKumo/trunk/FuwaKumo/CacheList.vb @ 34124

Public Class ImageCache(Of TKey, TValue As CacheItem(Of System.Drawing.Bitmap))
    Inherits Dictionary(Of TKey, TValue)

    Private _lifetimeHours As Integer
    Private _size As Integer

    Public Sub New()

    End Sub

    Public Sub New(ByVal lifetimeHours As Integer)
        _lifetimeHours = lifetimeHours
        _size = 20
    End Sub

    Public Shadows Sub Add(ByVal key As TKey, ByVal value As TValue)
        MyBase.Add(key, value)
        Truncate()
    End Sub

    Public Shadows Property Item(ByVal key As TKey) As CacheItem(Of System.Drawing.Bitmap)
        Get
            Dim cacheItem As CacheItem(Of System.Drawing.Bitmap) = MyBase.Item(key)
            cacheItem.CreatedAt = Now
            Return cacheItem
        End Get
        Set(ByVal value As CacheItem(Of System.Drawing.Bitmap))
            MyBase.Item(key) = value
        End Set
    End Property

    Public Property LifetimeHours() As Integer
        Get
            If _lifeTimeHours = Integer.MaxValue Then
                Return 0
            Else
                Return _lifetimeHours
            End If
        End Get
        Set(ByVal value As Integer)
            If value = 0 Then value = Integer.MaxValue
            _lifetimeHours = value
            Truncate()
        End Set
    End Property

    Private Sub Truncate()
        Dim keyList As New List(Of TKey)
        Dim lifeTime As DateTime = Now.AddMinutes(-5)
        For Each item As KeyValuePair(Of TKey, TValue) In Me
            If item.Value.CreatedAt.CompareTo(lifeTime) < 0 Then
                keyList.Add(item.Key)
            End If
        Next

        For Each key As TKey In keyList
            If Me.Item(key) IsNot Nothing Then
                Me.Item(key).Dispose()
                Me.Item(key) = Nothing
            End If
            Me.Remove(key)
        Next
    End Sub

End Class

Public Class CacheItem(Of T As IDisposable)
    Implements IDisposable

    Public CreatedAt As DateTime
    Private _value As T
    Public Sub New(ByVal Value As T)
        _value = Value
        CreatedAt = Now
    End Sub

    Public ReadOnly Property ItemData() As T
        Get
            CreatedAt = Now
            Return _value
        End Get
    End Property

    Private disposedValue As Boolean = False        ' �d�������яo����o������

    ' IDisposable
    Protected Overridable Sub Dispose(ByVal disposing As Boolean)
        If Not Me.disposedValue Then
            If disposing Then
                ' TODO: �����I�ɌĂяo���ꂽ�Ƃ��Ƀ}�l�[�W ���\�[�X�����
            End If

            ' TODO: ���L�̃A���}�l�[�W ���\�[�X�����
            If _value IsNot Nothing Then _value.Dispose()
        End If
        Me.disposedValue = True
    End Sub

#Region " IDisposable Support "
    ' ���̃R�[�h�́A�j��ȃp�^�[���𐳂�������ł�������Visual Basic �ɂ��Ēlj���������B
    Public Sub Dispose() Implements IDisposable.Dispose
        ' ���̃R�[�h��X���Ȃ��ł��������B�N���[���A�b�v �R�[�h���Dispose(ByVal disposing As Boolean) �ɋL�q���܂��B
        Dispose(True)
        GC.SuppressFinalize(Me)
    End Sub
#End Region

End Class