Question

Take the following:

if (filter instanceof FileNameExtensionFilter) {
    fnef = (FileNameExtensionFilter) filter;
    String[] extensions = fnef.getExtensions();
    if (extensions.length > 1) {
        fnef = filter = new FileNameExtensionFilter(fnef.getDescription(), extensions[0]);
    }
}

where filter is a FileFilter object and fnef an instance variable of the type FileNameExtensionFilter.

Would you consider it good coding practice to assign a value to multiple variables on the same line? Or would it be better to write line 6 from the example as follows:

fnef = new FileNameExtensionFilter(fnef.getDescription(), extensions[0]);
filter = fnef;

I personally prefer the latter, though I’d like to hear what you think.

Answer 1

This is a pretty subjective question.

I think this is more clear:

fnef = new FileNameExtensionFilter(fnef.getDescription(), extensions[0]);
filter = fnef;

But any experienced developer will understand this:

fnef = filter = new FileNameExtensionFilter(fnef.getDescription(), extensions[0]);