Launch many java programs at runtime

Hi i got one question.
i have a list of java program ina file.
i read this file and get each program names.
i would like to launch all java programs at Runtime from my main Java application.
here is my code so far:
String fileName = expansion + ".txt";
          try
               File file = new File(fileName);
               FileReader     fileReader= new FileReader(file);
               BufferedReader bufferReader = new BufferedReader(fileReader);
               while((program=bufferReader.readLine())!= null)
                    Runtime launch=Runtime.getRuntime();
                    System.out.println("I launch "+ program);
                    launch.exec("cmd.exe /c start /c cd /bin");
                    launch.exec("java "+program);
this does not work. How can i handle this?
thank you
seb

while((program==bufferReader.readLine())
!= null) {Sorry, I meant
while((program==bufferReader.readLine())!= null) {{=^)

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Edited by: 836590 on 14-Feb-2011 09:03

836590 wrote:
Hi,
I m calling an external java program by the command:
Runtime.getRuntime().exec("java -classpath \"library/*\" org.mypackage.TestMainProgram param1 c:/input/files c:/output/files");All my classes are stored in the relative directory "library", and it contains ONLY .jar files. However, I keep getting errors like:
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