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POProcessBuilder - Start another process / JVM - HowTo?
 

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    <p>I'm writing a network app, where each Client has a Singleton ClientManager. For <em>testing</em>, I would like to create several clients (each in their own VM / process) without starting the program by hand n-times.</p> <p>The following two questions on stackoverflow already describe how-to do that:</p> <ul> <li><a href="https://stackoverflow.com/questions/1229605/is-this-really-the-best-way-to-start-a-second-jvm-from-java-code">Is <em>this</em> really the best way to start a second JVM from Java code?</a> </li> <li><a href="https://stackoverflow.com/questions/636367/java-executing-a-java-application-in-a-separate-process/723914#723914">Java: Executing a Java application in a separate process</a></li> </ul> <p>My Code is based on these, but it's not working:</p> <ul> <li>The main program doesn't continue after spawn is called. </li> <li>The spawned code doesn't get executed.</li> </ul> <p>Here's the complete code using <a href="http://download.oracle.com/docs/cd/E17409_01/javase/6/docs/api/java/lang/ProcessBuilder.html" rel="nofollow noreferrer">ProcessBuilder</a>:</p> <pre><code>public class NewVM { static class HelloWorld2 { public static void main(String[] args) { System.out.println("Hello World"); System.err.println("Hello World 2"); } } public static void main(String[] args) throws Exception { startSecondJVM(HelloWorld2.class, true); startSecondJVM(HelloWorld2.class, false); System.out.println("Main"); } public static void startSecondJVM(Class&lt;? extends Object&gt; clazz, boolean redirectStream) throws Exception { System.out.println(clazz.getCanonicalName()); String separator = System.getProperty("file.separator"); String classpath = System.getProperty("java.class.path"); String path = System.getProperty("java.home") + separator + "bin" + separator + "java"; ProcessBuilder processBuilder = new ProcessBuilder(path, "-cp", classpath, clazz.getCanonicalName()); processBuilder.redirectErrorStream(redirectStream); Process process = processBuilder.start(); process.waitFor(); System.out.println("Fin"); } } </code></pre> <p>What am I doing wrong???</p> <p>Btw:</p> <ul> <li>I'm using Eclipse. </li> <li>The Singleton problem is a <em>simplified</em> example. Please do <em>not</em> suggest creating a factory.</li> </ul> <p><strong>Solution:</strong> HelloWorld2 mustn't be an inner class.</p>
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