Reliable Java libs for general programming

Question

There's always a balance when deciding whether to use a 3rd party library or write your own code. Writing your own takes time and will incur a maintenance cost. Using the 3rd party library has its downsides too, with the potential for version incompatibilities every time you update the dependencies.

With some libraries, the downsides are really light, and they're brought in as dependencies without much thought. For example, I use a couple of the apache commons libraries pretty much like the java.* packages - I'll pull in commons-lang or -io in just to use a single class. My justification for doing this is that the back compatibility of these libraries has been great so far, so they're unlikely to give me back compatibility problems in the future, and that they're likely to be on the classpath of some other library I'm relying on anyway.

Are there any other libraries that you bring in without worrying that back compatibility issues will hit you in the future?

Answer 1

The google collections library is very useful library that I have found to be very high quality.

Answer 2

I feel comfortable with pretty much everything from apache. I don't agonize too much over whether its going to be a pain in the future.

Answer 3

Joda Time is a high quality alternative to Java's awful inbuilt Date/Time APIs

Answer 4

Log4J works very well.

Answer 5

If it's a core business function, do it yourself no matter what.

Coding Horror has a post about it. Scroll down the page to get to the quote. If is referring to a Joel On Software article.

A lot of it will depend on how much support you might need to use the library. If there is a bug, is a workaround ok or do you REALLY need a patch. Do you have the time, skill, or inclination to fix a bug or extend a class and recompile the library while managing the version dependencies?

Answer 6

The Spring Framework is by far one of the best and most stable libraries I've used.

Answer 7

Implement a wrapper around 3rd party libraries

If you feel uncomfortable with a 3rd party library, you should consider to write a wrapper around it, that only provides the methods you really need.

This is most important if the library is used almost everywhere in your code. If it's only used in one class, writing a wrapper is useless, of course.

Write Unit Tests

Then write unit tests to verify that the needed functionality works (the way you use it).