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From: Andreas Leitgeb <avl@auth.logic.tuwien.ac.at>
Newsgroups: comp.lang.java.programmer
Subject: Re: dealing with ClassLoaders...
Date: Tue, 5 Aug 2014 15:16:27 +0000 (UTC)
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Mike Amling <mamling@chaff.us> wrote:
> On 8/4/14 10:12 AM, Andreas Leitgeb wrote:
>>              URL url=getSystemResource(name.replace('.', '/') + ".class");
>>              byte[] classData = new byte[1024*1024*10]; int len = 0;
>>              try {
>>                 len = url.openConnection().getInputStream().read(classData);
>>              } catch (IOException e) {
>>                 e.printStackTrace();
>>              }
> You could buffer to a ByteArrayOutputStream.
>       for (int input; (input=source.read())>=0; ) {
>          buffer.write(input);
>       }

Thanks for your answer. You made me re-think my irrational
resistance against coding a loop for that task. :-)

Now, the snippet looks like this:

   byte[] chunk = new byte[1024]; int len = 0;
   URL url = getSystemResource(name.replace('.', '/') + ".class");
   try {
      InputStream is = url.openConnection().getInputStream();
      ByteArrayOutputStream os = new ByteArrayOutputStream();
      while ((len = is.read(chunk)) > 0) { os.write(chunk,0,len); }
      chunk = os.toByteArray();
   } catch (IOException e) { chunk = null; }
   // if anything went wrong, there'll be an Exception on next line
   //   (be it NPE at chunk.length or from defineClass)
   res = defineClass(name,chunk, 0, chunk.length);

I think, that's good enough for me now. I declare my problem
as solved. :-)

Thanks again to all who participated in this thread!