c# create and print barcode Flyweight Pattern in C#.NET

Painting Code 3/9 in C#.NET Flyweight Pattern

Flyweight Pattern
ANSI/AIM Code 39 Generator In C#
Using Barcode creator for VS .NET Control to generate, create USS Code 39 image in VS .NET applications.
www.OnBarcode.com
Scan ANSI/AIM Code 39 In C#.NET
Using Barcode recognizer for .NET framework Control to read, scan read, scan image in VS .NET applications.
www.OnBarcode.com
Role
Barcode Maker In C#
Using Barcode drawer for .NET Control to generate, create Barcode image in .NET framework applications.
www.OnBarcode.com
Generate EAN 128 In C#
Using Barcode printer for VS .NET Control to generate, create EAN 128 image in .NET applications.
www.OnBarcode.com
The Flyweight pattern promotes an efficient way to share common information present in small objects that occur in a system in large numbers. It thus helps reduce storage requirements when many values are duplicated. The Flyweight pattern distinguishes between the intrinsic and extrinsic state of an object. The greatest savings in the Flyweight pattern occur when objects use both kinds of state but: The intrinsic state can be shared on a wide scale, minimizing storage requirements. The extrinsic state can be computed on the fly, trading computation for storage.
Code 128 Drawer In Visual C#.NET
Using Barcode generation for .NET framework Control to generate, create ANSI/AIM Code 128 image in VS .NET applications.
www.OnBarcode.com
Make Matrix 2D Barcode In C#.NET
Using Barcode generation for Visual Studio .NET Control to generate, create 2D Barcode image in VS .NET applications.
www.OnBarcode.com
60 |
QR Code Drawer In Visual C#.NET
Using Barcode encoder for Visual Studio .NET Control to generate, create QR Code image in .NET applications.
www.OnBarcode.com
Leitcode Drawer In C#
Using Barcode creator for .NET Control to generate, create Leitcode image in Visual Studio .NET applications.
www.OnBarcode.com
3: Structural Patterns: Composite and Flyweight
Make Code 39 In None
Using Barcode creation for Font Control to generate, create Code 39 image in Font applications.
www.OnBarcode.com
Code-39 Creation In Objective-C
Using Barcode creation for iPhone Control to generate, create Code-39 image in iPhone applications.
www.OnBarcode.com
Illustration
GS1 DataBar-14 Generator In Visual Studio .NET
Using Barcode printer for Visual Studio .NET Control to generate, create GS1 DataBar Truncated image in VS .NET applications.
www.OnBarcode.com
Make PDF417 In VS .NET
Using Barcode generation for .NET framework Control to generate, create PDF 417 image in VS .NET applications.
www.OnBarcode.com
Consider now the image aspect of the Photo Library application, as discussed with the Composite pattern. At any one time, we want to have a full page of images displayed and, with no discernable time lag, we want to be able to scroll up and down through the library. This implies that as many images as possible should be preloaded into memory and kept there while the photo application is running. For a Photo Group application, the primary function is to arrange photos in groups. Photos can belong to several different groups, so the number of images to display could increase enormously. If all of the images do not fit in memory, the fact that they can belong to different groups means that any given photo may be called up for display at irregular times, resulting in a lot of disk transfers. Consider the illustration in Figure 3-3. With a smaller window, the first two groups could have scrolled off the window by the time the Food group appears, requiring at least three of the images to be refetched and displayed. An object s unshared state is the set of groups to which it belongs. Its extrinsic state is the actual image, which is large it occupies about 2 MB. However, there are methods in the System.Drawing namespace to convert an image to a thumbnail of about 8 KB. This will be the object s intrinsic state, which is small enough to allow all the unique images to remain in memory at any one time. Through the group information, the application can display the images in various combinations. Using disk fetches, it can also show the complete original-sized images.
Recognizing QR Code ISO/IEC18004 In Visual Studio .NET
Using Barcode decoder for VS .NET Control to read, scan read, scan image in VS .NET applications.
www.OnBarcode.com
European Article Number 13 Maker In Objective-C
Using Barcode creation for iPad Control to generate, create EAN 13 image in iPad applications.
www.OnBarcode.com
Design
GTIN - 13 Creator In VS .NET
Using Barcode generation for Reporting Service Control to generate, create EAN13 image in Reporting Service applications.
www.OnBarcode.com
Data Matrix ECC200 Printer In None
Using Barcode printer for Font Control to generate, create ECC200 image in Font applications.
www.OnBarcode.com
Consider the UML diagram in Figure 3-4. As explained in the previous section, the Flyweight pattern relies on being able to divide up the application s state into three types. The intrinsicState resides in the Flyweight objects. The Flyweight class implements an IFlyweight interface, which specifies the operations upon which the rest of the system relies. The Client maintains the unSharedState as well as a dictionary of all the Flyweights, which it gets from a FlyweightFactory whose job it is to ensure that only one of each value is created. Finally, the extrinsicState does not appear in the system as such; it is meant to be computed at runtime for each instrinsicState instance, as required. The players in the Flyweight pattern are:
Universal Product Code Version A Generator In None
Using Barcode creation for Excel Control to generate, create UPC Symbol image in Microsoft Excel applications.
www.OnBarcode.com
Create Barcode In .NET Framework
Using Barcode encoder for Reporting Service Control to generate, create Barcode image in Reporting Service applications.
www.OnBarcode.com
Client
Scan Data Matrix 2d Barcode In VB.NET
Using Barcode decoder for .NET Control to read, scan read, scan image in .NET framework applications.
www.OnBarcode.com
Data Matrix 2d Barcode Printer In None
Using Barcode creator for Microsoft Word Control to generate, create DataMatrix image in Office Word applications.
www.OnBarcode.com
Computes and maintains the unshared state of the objects
IFlyweight
Defines an interface through which Flyweights can receive and act on intrinsic state
Flyweight Pattern
|
Client unSharedState FlyweightFactory flyweights : Dictionary <<interface>> IFlyweight +Operation( )
Flyweight intrinsicState +Operation( ) exintrinsicState computed at runtime
62 |
3: Structural Patterns: Composite and Flyweight
FlyweightFactory
Creates and manages unique Flyweight objects
Flyweight
Stores intrinsic state that is shareable among all objects There are other design options. For example, in Figure 3-4, the Flyweight is shown as computing the extrinsicState. However, the Client could do the computation and pass the extrinsicState to the Flyweight as a parameter to the Operation. Also, we envisage the unSharedState as a Dictionary of values related to the Flyweights; however, the unSharedState could have a more complex structure, warranting its own class. In this case, it would stand alongside the Flyweight class and implement the IFlyweight interface.
QUIZ
Match the Flyweight Pattern Players with the Photo Group Illustration
To test whether you understand the Flyweight pattern, cover the lefthand column of the table below and see if you can identify the players among the items from the illustrative example (Figure 3-4), as shown in the righthand column. Then check your answers against the lefthand column.
Copyright © OnBarcode.com . All rights reserved.