Re: To wrap or not to wrap?

From:
=?ISO-8859-1?Q?Arne_Vajh=F8j?= <arne@vajhoej.dk>
Newsgroups:
comp.lang.java.programmer
Date:
Thu, 08 May 2008 19:36:50 -0400
Message-ID:
<48238e86$0$90262$14726298@news.sunsite.dk>
Aaron Fude wrote:

On May 8, 7:13 pm, Arne VajhHj <a...@vajhoej.dk> wrote:

Aaron Fude wrote:

In my personal development efforts, I frequently wrap basic java
functionality. For example, I have a
String MyIO.urlToString(String url)
or
byte[] MIO.urlToBytes(String url)
etc. These functions catch exceptions and return null if something
goes wrong. I have other functoins that, for example, load database
queries into maps.
My gereneral questions are these. Does everybody pretty much end up
writing convenience wrappers like these for themselves?. If yes, why
aren't utilities like these commonly available as more or less
standard libraries? And if no - why not? Is it a bad idea to use these
and is it for some reason better to, e.g., always form URL's, open
connections, capture exceptions, etc.

I think it is a bad idea.

You should use the exception functionality as it is intended.


I kind of do. I capture the exception within the function and print
the error message. But wrapping this in a function in my project saves
me hundreds of lines of code, enables me not to have to remember how
things are done at the low level. For example, I have a function
called void playSoundClip(String fileName) and BufferedImage[]
loadImage(String fileName). I don't even remember the package that
deals with playing audio and Eclipse finds my own function for me
immediately.
When you say "should" can you elaborate why. When could this lead to
problem from the development point of view?


Testing for return values in a deep call stack adds lots of clutter to
the code.

Exceptions was invented to avoid that.

So catching the exception at the low level and convert to a return
value is a bad idea.

Arne

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