What are the drawbacks of software reuse? Explain.

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 Software Reuse 

- Software reuse is a term used for developing software by using the existing software components. Some of the components that can be reused are as follows;

• Source code

• Design and interfaces

• User manuals

• Software Documentation

- Software reuse is the process of implementing or updating software systems using existing software assets.

- In most engineering disciplines, systems are designed by composing existing components that have been used in other systems.

- Software engineering has been more focused on original development but it is now recognized that to achieve better software, more quickly and at a lower cost, we need a design process that is based on systematic software reuse.

- There has been a major switch to reuse-based development over the past 10 years.


Drawbacks of software reuse

The drawbacks of software reuse are described below:-

  • Increased maintenance costs: 

If the source code of a reused software system or component is not available, then maintenance costs may be higher because the reused elements of the system may become increasingly incompatible with system changes. 

  • Lack of tool support:

Some software tools do not support development with reuse. It may be difficult or impossible to integrate these tools with a component library system. The software process assumed by these tools may not take reuse into account. This is particularly true for tools that support embedded systems engineering, less so for object-oriented development tools.


  • Not-invented-here syndrome: 

Some software engineers prefer to rewrite components because they believe they can improve on them. This is partly to do with trust and partly to do with the fact that writing original software is seen as more challenging than reusing other people's software. 

  • Creating, maintaining, and using a component library: 

Populating a reusable component library and ensuring the software developers can use this library can be expensive. Development processes have to be adapted to ensure that the library is used.

  • Finding, understanding, and adapting reusable components: 

Software components have to be discovered in a library, understood, and, sometimes, adapted to work in a new environment. Engineers must be reasonably confident of finding a component in the library before they include a component search as part of their normal development process.


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