Comments on: Some final Patterns http://enfranchisedmind.com/blog/posts/some-final-patterns/ programming, politics, & other religious issues Mon, 15 Mar 2010 00:31:40 +0000 hourly 1 By: Enfranchised Mind » Functional (Meta)?Programming Stunts for Ruby and Groovy (and a Little Perl) http://enfranchisedmind.com/blog/posts/some-final-patterns/#comment-33406 Enfranchised Mind » Functional (Meta)?Programming Stunts for Ruby and Groovy (and a Little Perl) Tue, 24 Jun 2008 18:13:00 +0000 http://enfranchisedmind.com/blog/2007/12/16/some-final-patterns/#comment-33406 [...] final everywhere — see Yet Another Reason final Is Your Friend. A ubiquitous use of final actually gave some nice patterns (in the “macro” sense of patterns), but raised all kinds of eyebrows and made my code [...] [...] final everywhere — see Yet Another Reason final Is Your Friend. A ubiquitous use of final actually gave some nice patterns (in the “macro” sense of patterns), but raised all kinds of eyebrows and made my code [...]

]]> By: Enfranchised Mind » 2008 » April » 14 http://enfranchisedmind.com/blog/posts/some-final-patterns/#comment-33000 Enfranchised Mind » 2008 » April » 14 Mon, 14 Apr 2008 13:53:29 +0000 http://enfranchisedmind.com/blog/2007/12/16/some-final-patterns/#comment-33000 [...] the blog posting...Installing RMagick on Ubuntu: Problems I Encountered Doing "gem install RMagick"Some final PatternsStrongly Typed Languages Considered DangerousDefinitions of FreedomAnother Mason for Ron PaulMy [...] [...] the blog posting…Installing RMagick on Ubuntu: Problems I Encountered Doing “gem install RMagick”Some final PatternsStrongly Typed Languages Considered DangerousDefinitions of FreedomAnother Mason for Ron PaulMy [...]

]]> By: Robert Fischer http://enfranchisedmind.com/blog/posts/some-final-patterns/#comment-32978 Robert Fischer Tue, 08 Apr 2008 12:54:10 +0000 http://enfranchisedmind.com/blog/2007/12/16/some-final-patterns/#comment-32978 Yeah, now if some clever person would just come up with <a href="http://code.google.com/p/jconch/wiki/CacheMapExamples" rel="nofollow">a clever way of creating and caching immutable objects in a thread safe way</a>, we'd be set! Yeah, now if some clever person would just come up with a clever way of creating and caching immutable objects in a thread safe way, we’d be set!

]]> By: Hamlet D'Arcy http://enfranchisedmind.com/blog/posts/some-final-patterns/#comment-32970 Hamlet D'Arcy Tue, 08 Apr 2008 00:49:33 +0000 http://enfranchisedmind.com/blog/2007/12/16/some-final-patterns/#comment-32970 The last example about synchronizing on a non-final field isn't really contrived at all... There is no guarantee that all threads will see changes to non-final fields. So if thread A creates an object and sets the non-final field to a value in the constructor, there is no guarantee that thread B will see that value. It very well might do a read on the value and receive null. This happened to me last Fall and was quite reproducible (in that it happened maybe 1 in 10 times). Also, I learned two weeks ago how nice immutable objects are when it comes time to optimize your Java code for performance. It opens up a lot of caching possibilities when you don't have to worry about someone changing the state of your shared object. The last example about synchronizing on a non-final field isn’t really contrived at all… There is no guarantee that all threads will see changes to non-final fields. So if thread A creates an object and sets the non-final field to a value in the constructor, there is no guarantee that thread B will see that value. It very well might do a read on the value and receive null. This happened to me last Fall and was quite reproducible (in that it happened maybe 1 in 10 times).

Also, I learned two weeks ago how nice immutable objects are when it comes time to optimize your Java code for performance. It opens up a lot of caching possibilities when you don’t have to worry about someone changing the state of your shared object.

]]> By: Robert Fischer http://enfranchisedmind.com/blog/posts/some-final-patterns/#comment-32969 Robert Fischer Mon, 07 Apr 2008 21:50:51 +0000 http://enfranchisedmind.com/blog/2007/12/16/some-final-patterns/#comment-32969 I'm actually a fan of functional programming and immutable objects. However, in an OO world, the data within an object might change out from under you, and that's just the reality. However, you can at least keep your maintainers from being surprised when the parameter variable isn't the thing that was passed into the method. This is doubly important if you have certain checks (<code>null</code> being a popular one) that you're assuming for passing in. I’m actually a fan of functional programming and immutable objects. However, in an OO world, the data within an object might change out from under you, and that’s just the reality.

However, you can at least keep your maintainers from being surprised when the parameter variable isn’t the thing that was passed into the method. This is doubly important if you have certain checks (null being a popular one) that you’re assuming for passing in.

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