[kruffin]

I'd certainly prefer to be able to reason about the code with the safe assumption that certain things cannot be null.

You can do this, but if you want it to be maintainable, you'll also want to detail in the function comments this technical debt. If you don't, someone else will come along and see your sweet method (looking only at the comments) and use it where the input can be null.

Ex:

  /**
  * This does some stuff.
  * @param entry Does something with this
  * DEBT: Assumes the input entry is not null.
  */
  void doSomething(SomeObject entry) { }

[ycombobreaker]

Why just put it in the documentation? Documentation is liable to drift from implementation, and AFAIK no compiler or runtime verifies the accuracy of comments. I'd feel much better about adding asserts to the original code, leaving it for a few generations of testing and exposure, and then eventually remove the conditionals. The assert calls then function as executable documentation.

Depending on your user-base (i.e. if you distribute headers to other developers with precompiled code), the documentation may be necessary on its own... but it's much weaker than an assert.

[laureny]

Java has supported @Nullable and @Nonnull for a while, it's pretty standard in good Java code these days, and the IDE's will perform static analysis to make sure you use these annotations consistently (e.g. warn you if you are checking a @Nonnull against null or if you are forgetting to test a @Nullable against null before dereferencing it).

[pubby]

Is that C++? Just use a reference if you want a pointer which asserts it can't be null.

[kruffin]

It's Java ;P I haven't used C++ in a long time. But you are correct a reference does exactly what he wants.

For anyone who needs to look it up like me: http://en.wikipedia.org/wiki/Reference_(C%2B%2B)

[acomar]

Except the reference can itself be null, which is still problematic.

[happy_dino]

Why do you consider this a debt? It's pretty much the only sane thing to do.

If people want to pass lazy NullPointerExceptions, it's their fault.