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// Some imports |
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import java.util.*; |
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import java.lang.reflect.*; |
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|
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// This class is a wrapper for running applications |
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// a basic thread extension |
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class ApplicationThread extends Thread { |
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|
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// The constructor takes the name of the method we're gonna run |
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// and the arguments we're gonna pass into it |
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ApplicationThread(Method mainMethod, Object[] args) { |
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_mainMethod = mainMethod; |
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_args = args; |
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} |
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|
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// The main bit of the thread just starts the functionality of the given |
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// method running |
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public void run() { |
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try { |
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System.out.println(" Starting: "+ _mainMethod.getDeclaringClass().toString()); |
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_mainMethod.invoke(null, _args); |
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System.out.println(" Finished: "+ _mainMethod.getDeclaringClass().toString()); |
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} catch (Exception e){ |
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System.err.println("ERROR: " + e); |
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e.printStackTrace(System.out); |
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} |
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} |
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|
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Method _mainMethod = null; |
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Object[] _args = null; |
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} |
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|
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// The JVMManager takes a list of classes and instantiates them within the |
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// single VM that it is running in |
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// |
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// Future enhancements include: |
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// Passing of arguements to each class |
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// Seperation of in/out/err for each app |
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// GUI mode |
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// VM Thread control (ie, Kill, HUP etc...) |
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// Implementation of Java Security, specifically ProtectionDomain for each app |
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// |
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// Version 1.0 |
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// |
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// (c) Copyright 2000 Alex Moore |
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// |
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class JVMManager { |
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public static void main(String args[]) { |
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// no exceptions are yet caught - not good |
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try { |
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|
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// get hook on the runtime |
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Runtime myRuntime = Runtime.getRuntime(); |
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// get hook on the system Class loader |
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ClassLoader myClassLoader = ClassLoader.getSystemClassLoader(); |
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System.out.println("JVM Manager Started."); |
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System.out.println(" Total memory: " + myRuntime.totalMemory()); |
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System.out.println(" Free memory: " + myRuntime.freeMemory()); |
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System.out.println(); |
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|
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// for the time being we are just accepting a list of classes |
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// so just get the command line and assume that is just a simple list of classes to run |
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String[] appList = args; |
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|
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// step through each app, and start it rolling |
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for (int i=0; i < appList.length; i++) { |
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|
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// Load the class |
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Class myClass = myClassLoader.loadClass(appList[i]); |
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// and we don't support passing of individual args, but we will ;-) so its just null |
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String[] passedArgs = {}; |
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|
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System.out.println("*** Class Loaded: " + myClass.toString()); |
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|
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System.out.println(" Listing declared methods:"); |
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|
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// Just because we can, we're going to list the declared methods...no reason |
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Method[] theMethods = myClass.getDeclaredMethods(); |
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for (int x=0; x < theMethods.length; x++) { |
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System.out.println(" "+ theMethods[x].toString()); |
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} |
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|
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// create an array of classes that are listed in the main method header |
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// so we can get a hook to the main method |
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Class[] passedArgsClass = {passedArgs.getClass()}; |
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// get a hook on the main method |
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Method myMethod = myClass.getMethod("main",passedArgsClass); |
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|
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System.out.println(" Got a hook to the main method."); |
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System.out.println(" Creating and passing start up arguments to thread."); |
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|
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// Now we know where it is, we need to create a thread for it, passing in |
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// a list of objects that represent its args. |
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Object[] passedArgsObject = {passedArgs}; |
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ApplicationThread anApp = new ApplicationThread(myMethod, passedArgsObject); |
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|
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// Finally we start it going |
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System.out.println(" Starting Thread."); |
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anApp.start(); |
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|
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// Now we go and start the rest of the Apps listed |
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|
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} |
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|
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// At this point we are finished, though in the future the VM Manager |
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// won't just die away, but will remain to carry out JVM administration and |
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// thread management. |
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System.out.println(); |
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System.out.println("JVM Manager Finished."); |
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System.out.println(" Free memory: " + myRuntime.freeMemory()); |
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System.out.println(); |
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|
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} catch (Exception e) { |
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System.err.println("ERROR: " + e); |
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e.printStackTrace(System.out); |
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} |
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} |
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} |
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