java/src/main/com/google/appengine/tools/development/BackgroundThreadFactory.java

   1 // Copyright 2011 Google Inc. All Rights Reserved.
   2
   3 package com.google.appengine.tools.development;
   4
   5 import com.google.apphosting.api.ApiProxy;
   6
   7 import java.security.AccessController;
   8 import java.security.PrivilegedAction;
   9 import java.util.concurrent.ThreadFactory;
  10 import java.util.logging.Level;
  11 import java.util.logging.Logger;
  12
  13 /**
  14  * This {@link ThreadFactory} creates {@link Thread} objects that
  15  * live independent of the current request.  This means that they
  16  * receive their own {@code LocalEnvironment} and have their own set
  17  * of request ID and {@link RequestEndListener} objects.
  18  *
  19  */
  20 public class BackgroundThreadFactory implements ThreadFactory {
  21   private static final Logger logger = Logger.getLogger(BackgroundThreadFactory.class.getName());
  22
  23   private static final int API_CALL_LATENCY_MS = 20;
  24   private static final int THREAD_STARTUP_LATENCY_MS = 20;
  25
  26   private final String appId;
  27   private final String versionId;
  28
  29   public BackgroundThreadFactory(String appId, String versionId) {
  30     this.appId = appId;
  31     this.versionId = versionId;
  32   }
  33
  34   @Override
  35   public Thread newThread(final Runnable runnable) {
  36     final LocalBackgroundEnvironment environment = new LocalBackgroundEnvironment(appId, versionId);
  37
  38     final boolean callerNativeMode = DevSocketImplFactory.isNativeSocketMode();
  39
  40     sleepUninterruptably(API_CALL_LATENCY_MS);
  41     return AccessController.doPrivileged(new PrivilegedAction<Thread>() {
  42         @Override
  43         public Thread run() {
  44           Thread thread = new Thread(runnable) {
  45               @Override
  46               public void run() {
  47                 sleepUninterruptably(THREAD_STARTUP_LATENCY_MS);
  48                 DevSocketImplFactory.setSocketNativeMode(callerNativeMode);
  49                 ApiProxy.setEnvironmentForCurrentThread(environment);
  50                 try {
  51                   runnable.run();
  52                 } finally {
  53                   environment.callRequestEndListeners();
  54                 }
  55               }
  56             };
  57           System.setProperty("devappserver-thread-" + thread.getName(), "true");
  58           return thread;
  59         }
  60     });
  61   }
  62
  63   private void sleepUninterruptably(long sleepMillis) {
  64     try {
  65       Thread.sleep(sleepMillis);
  66     } catch (InterruptedException ex) {
  67       logger.log(Level.INFO, "Interrupted simulating latency:", ex);
  68       Thread.currentThread().interrupt();
  69     }
  70   }
  71
  72   private static class LocalBackgroundEnvironment extends LocalEnvironment {
  73     public LocalBackgroundEnvironment(String appId, String majorVersionId) {
  74       super(appId, majorVersionId);
  75     }
  76
  77     @Override
  78     public String getEmail() {
  79       return null;
  80     }
  81
  82     @Override
  83     public boolean isLoggedIn() {
  84       return false;
  85     }
  86
  87     @Override
  88     public boolean isAdmin() {
  89       return false;
  90     }
  91   }
  92 }