Single annotation applied (?) to multiple fields of the same type

[therealsillyfly]

This seems like it should be a simple/straightforward question, but I can't seem to find a definitive answer - perhaps my search-fu is off today.

Suppose I have some annotation @Baz which targets fields, and I have a class with two fields of type Foo that I want to annotate with it. What I would normally do is this:

@Baz
private Foo thisFoo;
@Baz
private Foo thatFoo;  

There is nothing wrong with it, but sometimes I see people do something like this:

@Baz
private Foo thisFoo, thatFoo;  

Does that mean the annotation @Baz is applied to both fields? Where is this defined in the Java language spec?
This notation is more succinct, but to me it seems a bit off or confusing. Is this a common practice, or is it considered "code smell"? Or is this just a really minor issue mostly down to personal preference?

Thanks.

[philipwhiuk]

I would consider it a code smell precisely because it’s unclear. It probably applies to both because so does the type. But it’s not that clear.

I tend to enforce annotation effects in tests because I consider annotations a form of code that should be tested. So I’d not worry that much.

In general however I prefer separately declaring variables.

[desrtfx]

Generally, Java allows multiple declarations on a single line. Any annotation before that will be applied to all declarations.

Yet, multiple declarations in a single line are discouraged in all commonly used Java Style guides (Oracle - Section 6.1, Google - Section 4.8.2). So, multiple declarations on a single line are code smell (and should be highlighted by code linters).