Ah yes, I see the distinction.
Very clever. So how exactly should we update the documentation?? :) michael On 25 Apr 2002, Phillip Lord wrote: > >>>>> "James" == James Carman <[EMAIL PROTECTED]> writes: > > James> No, each flyweight instance is not a singleton. It is a > James> single instance of a class, that's true. However, there are > James> also other instances of the same class. In the singleton > James> design pattern, exactly one instance of the class exists. In > James> the flyweight pattern, multiple instances of the class exist. > James> There are four AtomicSymbol instances created to represent > James> each of the a, g, c, and t DNA symbols. > > I think that the confusion comes from another related design pattern > which is a common way of faking enums in Java. So... > > > class Nucleotide{ > > private Nucleotide(){}; > > public static final Nucleotide a = new Nucleotide(); > public static final Nucleotide c = new Nucleotide(); > public static final Nucleotide g = new Nucleotide(); > public static final Nucleotide t = new Nucleotide(); > } > > is not a singleton either, but clearly looks like it. It's not really > a flyweight either, although it fulfils the same function where the > number of instances are known and defined at compile time. Personally > I consider it to be a singleton-ish method for nearly implementing a > flyweight. > > See this is the problem with computer programming. Someone spends all > this effort on synthesising only 23 patterns out of enormous > complexity. And then someone at the back stands up and says "ah but > what about....". > > A bit like biology really. There's always an exception to every rule. > > > Phil > _______________________________________________ > Biojava-l mailing list - [EMAIL PROTECTED] > http://biojava.org/mailman/listinfo/biojava-l > _______________________________________________ Biojava-l mailing list - [EMAIL PROTECTED] http://biojava.org/mailman/listinfo/biojava-l