src/dolda/jsvc/ThreadContext.java

   1 package dolda.jsvc;
   2
   3 import java.util.logging.*;
   4 import java.lang.reflect.*;
   5
   6 public class ThreadContext extends ThreadGroup {
   7     private Logger logger = Logger.getLogger("dolda.jsvc.context");
   8     private ThreadGroup workers;
   9     private long reqs = 0;
  10     private final ServerContext ctx;
  11     public final Responder root;
  12
  13     public ThreadContext(ThreadGroup parent, String name, ServerContext ctx, Class<?> bootclass) {
  14         super((parent == null)?(Thread.currentThread().getThreadGroup()):parent, name);
  15         this.ctx = ctx;
  16         workers = new ThreadGroup(this, "Worker threads") {
  17                 public void uncaughtException(Thread t, Throwable e) {
  18                     logger.log(Level.SEVERE, "Worker thread terminated with an uncaught exception", e);
  19                 }
  20             };
  21         root = bootstrap(bootclass);
  22     }
  23
  24     public void uncaughtException(Thread t, Throwable e) {
  25         logger.log(Level.SEVERE, "Service thread " + t.toString() + " terminated with an uncaught exception", e);
  26     }
  27
  28     public ServerContext server() {
  29         return(ctx);
  30     }
  31
  32     public void shutdown() {
  33         if(root instanceof ContextResponder)
  34             ((ContextResponder)root).destroy();
  35         try {
  36             long last = 0;
  37             while(true) {
  38                 long now = System.currentTimeMillis();
  39                 if(now - last > 10000) {
  40                     interrupt();
  41                     last = now;
  42                 }
  43                 Thread[] th = new Thread[1];
  44                 if(enumerate(th) < 1)
  45                     break;
  46                 th[0].join(10000);
  47             }
  48         } catch(InterruptedException e) {
  49             logger.log(Level.WARNING, "Interrupted while trying to shut down all service threads. Some may remain.", e);
  50         }
  51         destroy();
  52     }
  53
  54     public RequestThread respond(Request req) {
  55         return(new RequestThread(root, req, workers, "Worker thread " + reqs++));
  56     }
  57
  58     private Responder bootstrap(final Class<?> bootclass) {
  59         final Throwable[] err = new Throwable[1];
  60         final Responder[] res = new Responder[1];
  61         Thread boot = new Thread(this, "JSvc boot thread") {
  62                 public void run() {
  63                     try {
  64                         Method cm = bootclass.getMethod("responder");
  65                         Object resp = cm.invoke(null);
  66                         if(!(resp instanceof Responder))
  67                             throw(new ClassCastException("JSvc bootstrapper did not return a responder"));
  68                         res[0] = (Responder)resp;
  69                     } catch(NoSuchMethodException e) {
  70                         logger.log(Level.SEVERE, "Invalid JSvc bootstrapper specified", e);
  71                         err[0] = e;
  72                     } catch(IllegalAccessException e) {
  73                         logger.log(Level.SEVERE, "Invalid JSvc bootstrapper specified", e);
  74                         err[0] = e;
  75                     } catch(InvocationTargetException e) {
  76                         logger.log(Level.SEVERE, "JSvc bootstrapper failed", e);
  77                         err[0] = e;
  78                     }
  79                 }
  80             };
  81         boot.start();
  82         try {
  83             boot.join();
  84         } catch(InterruptedException e) {
  85             logger.log(Level.WARNING, "Interrupted during bootstrapping", e);
  86             boot.interrupt();
  87             Thread.currentThread().interrupt();
  88         }
  89         if(err[0] != null) {
  90             destroy();
  91             throw(new RuntimeException(err[0]));
  92         }
  93         if(res[0] == null) {
  94             destroy();
  95             logger.log(Level.SEVERE, "No responder returned in spite of no error having happened.");
  96             throw(new NullPointerException("No responder returned in spite of no error having happened."));
  97         }
  98         return(res[0]);
  99     }
 100
 101     public static ThreadContext current() {
 102         for(ThreadGroup tg = Thread.currentThread().getThreadGroup(); tg != null; tg = tg.getParent()) {
 103             if(tg instanceof ThreadContext)
 104                 return((ThreadContext)tg);
 105         }
 106         return(null);
 107     }
 108 }