Java IAQ

Goes directly to "What other operations are surprisingly slow?" and attempts to write micro benchmark with the same results.<p>Fails....<p>Most of the general stuff is accurate and dandy but I don't believe you should listen to many (most likely any) of the speed related statements as this article appears to have been written in 1998.<p>Topic should be "Java IAQ circa 1998".

I have an IAQ of my own:<p>Why is it that Java VMs seem to have such different interactive latency when compared to other memory-managed language VMs? Is the performance of eg, eclipse or Android or the Java browser plugin something to with the GC kicking in too aggressively?<p>Over the last decade I've heard different explanations re: SWT/swing/AWT toolkits, and server-side optimizations being default in desktop VMs, but I'm fairly sure both issues should be resolved now. Nevertheless, my general experience seems to be if it's Java based, it seems to handle touch/mouse events noticeably worse than otherwise.<p>Maybe .net and Python and the rest are doing more of their UI work in C?

If you are interested in this kind of stuff, Effective Java is a must-read book. Long, good explanations of how to do stuff right.<p>Also, the 2nd edition covers up through Java 1.6.

FWIW, last changed July 13, 1998 according to the source.

This appears to have been written before IDEs were invented. The author suggests that it's acceptable to extend a class just to gain unqualified access to its static methods to save a few characters of typing.

<i>Java compilers are very poor at lifting constant expressions out of loops. The C/Java for loop is a bad abstraction, because it encourages re-computation of the end value in the most typical case. So for(int i=0; i&#60;str.length(); i++) is three times slower than int len = str.length(); for(int i=0; i&#60;len; i++)</i><p>Does anyone know if this is still valid advice? I recall reading somewhere that the JIT has optimized around this problem.

<i>But note the warning from Sun: "So when should you use static import? Very sparingly!"</i><p>I'm so glad there is an authoritative answer on this subject. IMHO, I hate the use of static imports because it becomes difficult to know where a particular method comes from... where it's an instance method from the class itself or one that is brought in through a static import.<p>And then there's the possibility of clobbering the namespace by including a local variable name and a statically imported variable.

The page links also to a C IAQ: <a href="http://www.seebs.net/faqs/c-iaq.html" rel="nofollow">http://www.seebs.net/faqs/c-iaq.html</a><p>I've never seen that many wrong C statements. :-)

A little outdated, the one about HashMaps and equals is moot with generics.<p>Still quite interesting.