Re: Hidden features of java
Dirk Bruere at NeoPax wrote:
I read somewhere that Java has over 4500 classes.
Anyone here used more than 1000?
Arved Sandstrom wrote:
Directly used, out of "standard" APIs like J2SE and J2EE? I'm over the
10-year mark for using Java (obviously not by much :-)) and I doubt that
I've even come close to 1000. On a month-to-month basis on any given
J2SE/Java EE project there's probably no more than fifty or so standard
classes involved that I use directly, and only a small percentage of the
methods they provide.
A more meaningful metric than how many classes a single programmer
used would be how many programmers used a particular class. Either
way, it's a specious argument.
If some programmer by chance has never used, say, any classes from
java.util.concurrent, does that mean that the package shouldn't exist?
I wager that only a handful of programmers have used
java.lang.SecurityManager, yet it would be very difficult to make a
case that it should be removed from the API.
APIs aren't there for popularity - they're there because a solid
implementation is sometimes (or perhaps frequently) needed, and it's
good to have a reliable one in the standard API for those (perhaps
infrequent) times when one absolutely must have it.
A similar argument applies even to language features. Look how long
it's taking people to warm to generics, or even 'assert', which has
been here since 1.4, yet both are extremely useful and arguably
mandatory.
As for APIs, you may never yet have used
java.util.concurrent.CopyOnWriteArrayList<E>, but if and when you need
that functionality you will be mighty glad that the API already has
it. Another meaningful question is how many Java programs out there
have custom implementations of classes that already existed in the API
when they were written, only the programmer didn't know it?
--
Lew