Two Random things I like about Java...

1) the fact that each and every class file needs to have 0xCAFEBABE in the first 4 byte positions

This actually identifies the file as a valid Java class file in addition to the file extension, no non-class file is likely to have this number in that location.

2 the fact that there is a class called java.text.DontCareFieldPosition!!

The name actually makes sense, it's used by the DecimalFormatter and is package-local, so clients of the API should never be aware of it, and is a null implementation of the FieldPosition interface. Cudos to the developer that argued that name past the API police!!