Obsolete vs. deprecated in software development
The key difference between a deprecated component and an obsolete component is that a deprecated component is fully functional but scheduled to be phased out, while an obsolete item has been fully phased out and cannot be used in a modern environment.
What is a deprecated method?
In software development, components are commonly listed as deprecated. If a feature or function is deprecated, developers are warned that support for that feature will be withdrawn in the near future. When that happens, old code will no longer work on new releases, forcing developers to rewrite, retest, and reintegrate it into their codebase.
Forward-thinking developers avoid using deprecated classes, methods and functions. This shouldn’t be hard, as documentation typically points to preferred ways to achieve the same functionality when deprecation occurs.
What does it mean to be obsolete?
Something that is obsolete has completely lost its usefulness. In software development, a resource that has been made obsolete can no longer be used, and attempts to do so will result in either a runtime error or compile-time error.
More generally, an item may become obsolete when its use is dangerous, it has well-known security flaws, it is no longer produced, or it has been replaced by something significantly better.
| Examples of obsolete and deprecated items | |
|---|---|
| Obsolete items | Deprecated items |
| Adobe Flash Player | Thread.stop() in Java |
| Windows 3.1 | HTML’s <marquee> tag |
| Google+ | Date.getYear() in Java |
| Java Applets | UIWebView in iOS |
| Floppy Disks | System.runFinalizersOnExit() in Java |
In summary, avoid using deprecated components, because they are being phased out, while an item that is obsolete has been completely phased out and can’t be used.