On Mar 27, 2015, at 3:01 PM, Martin Buchholz <marti...@google.com> wrote: > > final Type foo = this.foo;
There are IMO a few places where local finals pay for themselves, even after Java 8. One is Martin's idiom. The key thing to observe is that 'foo' is a read-only snapshot or view of 'this.foo'. If we were after conciseness (only) we could delete the whole line, but the line as a whole has a clear purpose. Another reasonable use of local finals is when writing SSA-style code. A blank final enforces SSA, and makes it clearer what's going on. If I'm writing a large, complex loop and I want to make it clear that something is loop-invariant, I sometimes use a final. But in cases like that it's better to factor the loop body into a separate method, if that is possible. Another place I like finals is where I am capturing values which are constants, sampled from a variable (e.g., "cursor++"). In that case, the different declaration makes clear the distinction between a snapshot and a varying cursor. This is of course a matter of taste. In all these cases the benefits are only present when the affected variable has a large or complex live range. So the best use cases are always going to give the onlooker a sense of unease. In simple use cases, "final" is just noise, but in complex ones it can help solidify the reader's understanding. — John
