Can a java application ever be as responsive as a native alternative [closed]

Question

To my experience, most of java applications on desktop platforms are less responsive than a similar application written in c++ or some other natively compiled language. Which is understandable considering that java only compiles to intermediate language.

And by responsiveness here I mean the general feel of how the application responds to mouse clicks and keyboard events, the little lags between the user clicking somewhere and the program actually redrawing all the needed things to represent the response to that click. Most often these lags are so small that you don't see them as lag, but you get a feeling that the whole aplication gets a little slow.

Examples of such java applications that I would see as less responsive are Azureus, java-based versions of Zend studio, Eclipse, and a couple of my own swing-based java projects.

Is this really the case? Can a java application ever be as responsive as a native application? Should it perhaps be compiled in some different way? (although you would think that if that was possible, big products such as Zend studio would do that already)

Answer 1

Application responsiveness in Java is frequently down to bad/inefficient programming. While a Java UI is heavier than one written in C/C++, on a recent computer (last few years or so) shouldn't struggle with a well coded application.

Most recent benchmarks show Java 1.6 to be of comparative speed to C/C++ (infact in the last cross language benchmarks I saw it sat snugly between the two in terms of performance).

I think a symptom of Java and the IDEs people use to write it is that it is a forgiving language that lets you do things the wrong way (read, less good way), without complaining too much while C++ would just fall over, forcing you to write better software.

As a personal note, I've seen Java applications where the devs attached a single listener to every element in the UI, then that listener had an enormous if...elseif...elseif... to check the tooltip string that was passed back from the event object.

Answer 2

javac compiles to an intermediate byte code. However the JVM compiles to native code based on how the code is used dynamically (something static compilers cannot do) For GUIs most of the real work is done in native code components so you shouldn't see a real difference.

Many real time trading systems are developed using Java and respond in less than 100 micro-seconds. i.e. 0.0001 seconds. If you have a responsiveness issue, its not the language at fault.

BTW: Eclipse uses SWT which is a native library.