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Proxy Pattern Code Review
Code Download
- Download Description:proxy pattern download
- .NET Framework:3.5
- .NET Language:C#
- Date Published:2009-07-01
- Download Size:48 KB
Use the Proxy Pattern
Define the IPicture interface represents the "blueprint" for a set of complex classes (objects).
class PictureAccessor
{
public interface IPicture
{
System.Drawing.Image getImage();
}
The LoadPicture class (object) inherits from the IPicture interface and represents one type of "complex" class.
private class LoadPicture : IPicture
{
public System.Drawing.Image getImage()
{
return new System.Drawing.Bitmap("loading.jpg");
}
}
The FinalPicture class (object) inherits from the IPicture interface and represents another type of "complex" class.
private class FinalPicture : IPicture
{
public System.Drawing.Image getImage()
{
return new System.Drawing.Bitmap("blueskysailboat.jpg");
}
}
The PictureProxy class manages the creation of the "complex" classes and provides a single interface for the client.
public class PictureProxy : IPicture
{
private Boolean loaded = false;
private Boolean authenticated = false;
private IPicture pic = null; private System.Threading.Timer timer = null;
public PictureProxy() { try { this.loaded = false; this.authenticated = false; this.timer = new System.Threading.Timer(new System.Threading.TimerCallback(timer_CallBack), this, 5000, 0); } catch { throw; } }
public System.Drawing.Image getImage() { if (authenticated) { if (this.pic == null) { if (this.loaded) { this.pic = new FinalPicture(); } else { this.pic = new LoadPicture(); } } return pic.getImage(); } else { return null; } } public void Authenticate(String password) { if (String.Compare(password, "Abracadabra") == 0) { this.authenticated = true; } else { this.authenticated = false; } } private void timer_CallBack(Object obj) { try { this.loaded = true; this.pic = null; this.timer.Dispose(); } catch { throw; } } } }
private IPicture pic = null; private System.Threading.Timer timer = null;
public PictureProxy() { try { this.loaded = false; this.authenticated = false; this.timer = new System.Threading.Timer(new System.Threading.TimerCallback(timer_CallBack), this, 5000, 0); } catch { throw; } }
public System.Drawing.Image getImage() { if (authenticated) { if (this.pic == null) { if (this.loaded) { this.pic = new FinalPicture(); } else { this.pic = new LoadPicture(); } } return pic.getImage(); } else { return null; } } public void Authenticate(String password) { if (String.Compare(password, "Abracadabra") == 0) { this.authenticated = true; } else { this.authenticated = false; } } private void timer_CallBack(Object obj) { try { this.loaded = true; this.pic = null; this.timer.Dispose(); } catch { throw; } } } }