What are the advantages and disadvantages of using template classes?

Answer 1

A document or file having a preset format, used as a starting point for a particular application so that the format does not have to be recreated each time it is used: a loan amortization template for a spreadsheet program.

Answer 2

It depends on the type of template you are referring to. Generally, if a template is provided that meets your needs, then you save a great deal of time by not having to start from scratch. The template should provide the basic framework you need, and should permit some measure of modification to tailor it to your exact requirements.

To look at a more specific computer programming example, a template function or class allows you to provide a single, generic implementation that can cater for any data type that supports that implementation. For instance, all linked lists operate exactly the same way regardless of the type of data stored in the list. So rather than implement separate lists for every type of data you might wish to place in a list (which is a maintenance nightmare should you wish to modify the implementations), or derive lists from an abstract list class (which is problematic at best), you simply provide one template class and construct specific lists with specific data types as and when required. Since the implementation is entirely self-contained and all in one place, with little to no code duplication, code maintenance is greatly simplified and type-safety is assured. And if you need a more specific type of list (such as a priority queue or a stack), then you can derive from the generic list template to create other generic templates that implement the more specific features you require. Of course lists, queues and stacks are usually provided for you in your chosen language anyway, so you rarely need to implement your own templates, but it's a classic example of why templates are useful in computer programming.

Answer 3

Template is used to implement the concept of generic programming. Templates allow us to generate a family of classes or a family of functions to handle different data types

Answer 4

If there is more than one shape needed, you use the tamplate to re-use again to make the same shape.