Why is java.io.InputStream.read() so slow???

Hi everyone,
I have an applet that reads a file via url. I open the file and read from it using this code:
URL url = new URL (http://"www.somesite.com/target.txt");
try {
InputStream is = url.openStream();
//reads the raw data from the file
for(int i = 0; i != -1;) {
i = is.read();
//determines dimensions needed for the array
if(i == '~') {
dataDimension++;
rawData += (char) i;
}catch(IOException ioe) {}
The code works without errors. (hopefully the above does too, I dont think I introduced any errors when I pasted it over...) The problem is it is unbelieveably slow. When I run it on my file of 85kB in size, the code runs for several minutes on this loop reading in the data in the file. I have no idea why this is...the problem appears to have little or nothing to do with bandwidth as ive tried it on dsl, 56K etc. Ive even writtin a variant that reads the data off my hard drive. No matter where the file resides and how fast of a pipe I give it, it takes just about the same time to complete. My assumption is that either Strings have an increasingly harder time concatenating another string to its end as its size increases or InputStream needs to be layered in another reader object for some strange reason.
Does anyone have any idea whats happening here? Is there a faster way to get characters from a file into a String?
I really do appreciate any help I get on this one!
Thanks in advance for posting.
Sincerely,
Nickolas Fellows
[email protected]

Haha, Im an idiot...I answered my own question...or at least I think I did.
Turns out I shoulda been using a StringBuffer and initializing it with a size large enough to hold the file right off the bat. I am assuming making the string recreate its self everytime its size got exceeded was the problem.
Thx for letting me waste everyones time again :)
Sincerely,
Nickolas Fellows
[email protected]

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http://stackoverflow.com/questions/1107991/why-does-java-have-such-a-large-footprint
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yangzhang wrote:
I've been curious about this topic for a while, but I haven't ever looked into this to any depth. I also posted this to stackoverflow but haven't gotten any solid responses so far:
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Java - or at least Sun's Hotspot JVM - has long had a reputation for having a very large memory footprint. What exactly is it about the JVM that gives it this reputation? I'd be interested in a detailed breakdown: how much memory goes to the runtime? (The JIT? The GC/memory management? The classloader?) Anything related to "auxiliary" APIs like JNI/JVMTI? The standard libraries? (Which parts get how much?) Any other major components?
Presumably versus some other VM. I would suppose the fact that much of the VM is written in java has something to do with it.
I realize that this may not be straightforward to answer without a concrete application plus VM configuration, so just to narrow things down at least somewhat: I'm primarily interested in default/typical VM configurations, and in a baseline console "Hello world" app as well as any real-world desktop or server app. (I'm suspecting that a substantial part of the JVM's footprint is largely independent of the app itself, and it is in this part that I'd like to zoom in, ideally.)
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