Can interface description

An interface description can contain:. After you run the undo portswitch command to switch Layer 2 interfaces on the preceding series of switches into Layer 3 interfaces, you can configure Ethernet sub-interfaces on the interfaces. After an interface is added to an Eth-Trunk, sub-interfaces cannot be configured on the interface. Configuring an Interface Description Context To facilitate switch management and maintenance, you can configure interface descriptions.

Compatible Table. Cable Routing. Device Manager and Hardware Installation. Install the driver before you install the interface into the S-Panel PC. The driver installation media for the CANopen interface is included with the package. After the interface is installed, you can verify whether it is properly installed on your system through the Device Manager. NOTE: If you see your device name listed on it but marked with an exclamation sign! In this case, remove the device from the Device Manager by selecting its device name and press the Remove button.

Then go through the driver installation process again. The figure shows the CANopen interface:. There is no code after the function prototype. To tell the computer that a new class that you are writing will fulfill all the requirements implement all the functions of an interface, you must use the keyword implements in the same location where you can use the keyword extends. Remember: While all functions in the interface must be implemented in the class, you can also create any other functions you want for that class.

What is the power of the interface? The power is that once we have a number of classes which implement the interface, from some point of view, they are equivalent.

For example, say we want to create a Car and a Truck, but all our program wants to do is "start" them and "drive" them. To our program's "point of view" they are just Vehicles. Below are examples showing how we would write the code without interfaces, with interfaces, and then with a generic arrays of "Vehicles".

The final example above shows the concept of Polymorphism. Polymorphism is the idea that an compile time coding time we don't know and often can't know what the actual type of object inside a variable will be. In the vehicles array above, we don't know if vehicles[i] is a car, truck, bicycle, etc.

In computer languages without polymorphism, we wouldn't be able to do anything with these objects. With polymorphism, the computer remembers what each is and when we say: "item. Polymorphism save the programmer a lot of time and effort in coding up "exceptional" conditions. The computer does the work for us, a remembering what each object really is, and then b at run time, invoking the actual function associated with the current object.