Design Mode: Command mode

I read the blog of Yunfei Longxing, which is very good.

Http://www.cnblogs.com/sjms/archive/2010/07/09/1774069.html

 

The customer only sends commands (requests), and the customer does not care who accepts them and how to execute them.

Definition: encapsulate a request (command) as an object.

Command mode is the encapsulation of commands. The command mode separates the responsibility for issuing commands from the responsibility for executing commands and delegates them to different objects.

Each Command is an operation: the Requesting Party sends a request to execute an operation; the receiving party receives the request and performs the operation.

The command mode allows the requester and the receiver to be independent, so that the requester does not have to know the interfaces of the receiver,

You do not need to know how the request is received, whether the operation is executed, when it is executed, and how it is executed.

 

Command mode: You need to define a command interface to constrain all command objects. And provides specific command implementation.

Each command implementation object is a specific encapsulation of a client request(Although it is a virtual implementation)

Each button of the chassis corresponds to a specific command implementation.

The command object does not know how to handle the command. He holds a command ReceiverCycler, Which is implemented by the aggreger.

In command mode: command and receiver are not inherent.Client completedCommandAndCycler.

Invoker: the requester holds a reference to the command object.

There are many buttons on the chassis. The chassis is invoker.