Design Pattern-Structure Pattern

I. Summary of the structural mode:

 

Ii. Detailed analysis:

1. (Adapter) Adapter mode Diagram

 

 

Adapter adapter mode: creates an interface to use a class of existing incompatible interfaces. The main application is to add new functions to system maintenance.

Usage process: provides an access interface for the object to be used, so that the target object functions are integrated into the system.

Life example: a typical example is a laptop power supply.

2. Proxy Mode

 

Proxy proxy mode: the proxy object is used to control the reference to the original object, and its interface cannot be changed.

3. decorator decorative pattern Diagram

 

 

 

Public ClassTest

{

Public Static VoidMain (string [] ARGs)

{

Errorlog =NewErrorlog ();

Decoratelog errorlogabve =NewDecoratelog (errorlog );

System.Out. Println ("errorlogabove :");

Errorlogabove. printmessage ();

 

Dubuglog =NewDubuglog ();

Decoratelog dubuglogabve =NewDecoratelog (errorlogabove, dubuglog );

System.Out. Println ("dubuglogabove :");

Dubuglogabove. printmessage ();

 

Inforlog =NewInforlog ();

Decoratelog inforlogabve =NewDecoratelog (dubuglogabove, inforlog );

System.Out. Println ("inforlogabove :");

Inforlogabve. printmessage ();

}

}

 

Abstract ClassLog

{

Public Abstract VoidPrintmessage ();

}

 

ClassDecoratelogExtendsLog

{

 

Log log1;

Log log2;

 

PublicDecoratelog ()

{

}

 

PublicDecoratelog (log log1)

{

This. Log1 = log1;

}

 

PublicDecoratelog (log log1, log log2)

{

This. Log1 = log1;

This. Log2 = log2;

}

 

Public VoidPrintmessage ()

{

If(Null! = Log1)

Log1.printmessage ();

If(Null! = Log2)

Log2.printmessage ();

}

}

 

ClassErrorlogExtendsLog

{

Public VoidPrintmessage ()

{

System.Out. Println ("error information ");

}

}

 

ClassDubuglogExtendsLog

{

Public VoidPrintmessage ()

{

System.Out. Println ("dubuglog information ");

}

}

 

ClassInforlogExtendsLog

{

Public VoidPrintmessage ()

{

System.Out. Println ("inforlog information ");

}

}

Decorator decoration mode: dynamically add some new operations and functions to the target object.

4. Appearance Pattern

 

Facade appearance mode: shields subsystem components from the system to reduce the coupling between the client and the system.

Life example: send a text message to check the phone bill. The applications in the project are databases. (The implementation of the datautil class is facade)

5. Bridge Mode Diagram

 

Bridge Mode: separates the abstraction and implementation of the system, and facilitates the implementation of layered architecture. Reduce the code modifications caused by changes.

PackageCom. Test. bridge;

 

Public ClassTest

{

Public Static VoidMain (string [] ARGs)

{

Abstractroad road1 =NewSpeedway ();

Road1.car =NewCar ();

Road1.run ();

}

}

 

Abstract ClassAbstractcar

{

Public Abstract VoidRun ();

}

 

ClassCarExtendsAbstractcar

{

Public VoidRun ()

{

 

System.Out. Println ("car in ");

}

}

 

ClassBusExtendsAbstractcar

{

Public VoidRun ()

{

 

System.Out. Println ("Bus in ");

}

}

 

Abstract ClassAbstractroad

{

Abstractcar car;

 

Public Abstract VoidRun ();

}

 

ClassSpeedwayExtendsAbstractroad

{

Public VoidRun ()

{

 

Car. Run ();

System.Out. Println ("driving on highway ");

}

}

 

ClassStreetExtendsAbstractroad

{

Public VoidRun ()

{

 

Car. Run ();

System.Out. Println ("driving on a street in a city ");

}

}

Living instance: device switch

6. Combined Mode Diagram

 

Composite combination mode: ensures consistency of object usage.

In terms of structure and decorate, the two modes are usually implemented together.

PackageCom. Test. composite;

 

ImportSun. Reflect. generics. reflectiveobjects. notimplementedexception;

ImportJava. util .*;

 

Public ClassTest

{

Public Static VoidMain (string [] ARGs)

{

// Construct the root node

Composite rootcomponent =NewComposite ("root ");

 

// Add two leaves, that is, child parts

Leaf leaf1 =NewLeaf ("leaf1 ");

Leaf leaf2 =NewLeaf ("leaf2 ");

 

Rootcomponent. Add (leaf1 );

Rootcomponent. Add (leaf2 );

 

// Traverse Components

Rootcomponent. eachchild ();

}

}

 

Abstract ClassComponent

{

String name;

 

PublicString getname ()

{

ReturnName;

}

 

Public VoidSetname (string name)

{

This. Name = Name;

}

 

// Add part

Public Abstract VoidAdd (Component component );

 

// Delete part

Public Abstract VoidRemove (Component component );

 

// Traverse all child parts

Public Abstract VoidEachchild ();

}

 

ClassLeafExtendsComponent

{

PublicLeaf ()

{

}

 

PublicLeaf (string name)

{

This. Name = Name;

}

 

// Leaf nodes cannot be added.

Public VoidAdd (Component component)

{

Throw NewNotimplementedexception ();

}

 

// The leaf node cannot be deleted because it cannot be added.

Public VoidRemove (Component component)

{

Throw NewNotimplementedexception ();

}

 

// The execution result is displayed because no child node exists on the leaf node.

Public VoidEachchild ()

{

String STR = string.Format(Name + "executed ..");

System.Out. Println (STR );

}

}

 

ClassCompositeExtendsComponent

{

PublicComposite ()

{

}

 

PublicComposite (string name)

{

This. Name = Name;

}

 

// The component used to save the combination

List <component> mylist =NewArraylist <component> ();

 

// Add a node and add a part

Public VoidAdd (Component component)

{

Mylist. Add (component );

}

 

// Delete a node to delete a part

Public VoidRemove (Component component)

{

Mylist. Remove (component );

}

 

// Traverse subnodes

Public VoidEachchild ()

{

String STR = string.Format(Name + "executed ..");

System.Out. Println (STR );

For(Component C: mylist)

{

C. eachchild ();

}

 

}

}

 

 

7. Metadata Mode

 

Share mode: Use the sharing technology to effectively support a large number of fine-grained objects

 

 

Design Pattern-Structure Pattern