Functional Programming in Java, 2nd Edition

Wrapping Up

Dealing with failure is hard, both in life and in programming. Exception handling is fundamentally an imperative style of programming idea, and we can’t mix exceptions and functional style code. One way to deal with failures is to treat errors as forms of data. In this chapter we took a close look at how to do this with a practical example. The solution is effective in handling errors but makes the code a tad complex and less cohesive. Use caution in how you deal with errors when writing functional style code.

In the next chapter we’ll apply our learnings by taking some legacy code written using the imperative style and turning it into functional style.

Footnotes

[16]

https://en.wikipedia.org/wiki/Union_type

[17]

https://www.scala-lang.org/api/2.13.6/scala/util/Try.html ...