1 package sample.evolve; 2 3 import javassist.*; 4 5 /** 6 * DemoLoader is a class loader for running a program including 7 * an updatable class. This simple loader allows only a single 8 * class to be updatable. (Extending it for supporting multiple 9 * updatable classes is easy.) 10 * 11 * To run, type as follows: 12 * 13 * % java sample.evolve.DemoLoader <port number> 14 * 15 * Then DemoLoader launches sample.evolve.DemoServer with <port number>. 16 * It also translates sample.evolve.WebPage, which sample.evolve.DemoServer 17 * uses, so that it is an updable class. 18 * 19 * Note: JDK 1.2 or later only. 20 */ 21 public class DemoLoader { 22 private static final int initialVersion = 0; 23 private String updatableClassName = null; 24 private CtClass updatableClass = null; 25 26 /* Creates a <code>DemoLoader</code> for making class WebPage 27 * updatable. Then it runs main() in sample.evolve.DemoServer. 28 */ 29 public static void main(String[] args) throws Throwable { 30 Evolution translator = new Evolution(); 31 ClassPool cp = ClassPool.getDefault(); 32 Loader cl = new Loader(); 33 cl.addTranslator(cp, translator); 34 35 translator.makeUpdatable("sample.evolve.WebPage"); 36 cl.run("sample.evolve.DemoServer", args); 37 } 38 } 39
