java/src/main/com/google/appengine/tools/remoteapi/ThreadLocalDelegate.java

   1 // Copyright 2011 Google. All Rights Reserved.
   2 package com.google.appengine.tools.remoteapi;
   3
   4 import com.google.apphosting.api.ApiProxy;
   5 import com.google.apphosting.api.ApiProxy.Delegate;
   6 import com.google.apphosting.api.ApiProxy.Environment;
   7
   8 import java.util.List;
   9 import java.util.concurrent.Future;
  10
  11 /**
  12  * An {@link ApiProxy.Delegate} implementation that allows users to install
  13  * another {@link ApiProxy.Delegate} that is only visible to the current
  14  * thread.  If there is nothing associated with the current thread, the global
  15  * delegate provided as a constructor argument is used instead.
  16  *
  17  */
  18 class ThreadLocalDelegate<E extends Environment> implements ApiProxy.Delegate<E> {
  19
  20   private final Delegate<E> globalDelegate;
  21
  22   private final ThreadLocal<Delegate<E>> threadLocalDelegate;
  23
  24   ThreadLocalDelegate(Delegate<E> globalDelegate, Delegate<E> threadDelegate) {
  25     this.globalDelegate = globalDelegate;
  26     this.threadLocalDelegate = new ThreadLocal<Delegate<E>>();
  27     this.threadLocalDelegate.set(threadDelegate);
  28   }
  29
  30   Delegate<E> getDelegate() {
  31     ApiProxy.Delegate<E> result = threadLocalDelegate.get();
  32     if (result == null) {
  33       result = globalDelegate;
  34     }
  35     return result;
  36   }
  37
  38   public byte[] makeSyncCall(E environment, String pkg, String method, byte[] bytes)
  39       throws ApiProxy.ApiProxyException {
  40     return getDelegate().makeSyncCall(environment, pkg, method, bytes);
  41   }
  42
  43   public Future<byte[]> makeAsyncCall(E environment, String pkg, String method, byte[] bytes,
  44       ApiProxy.ApiConfig apiConfig) {
  45     return getDelegate().makeAsyncCall(environment, pkg, method, bytes, apiConfig);
  46   }
  47
  48   public void log(E environment, ApiProxy.LogRecord logRecord) {
  49     getDelegate().log(environment, logRecord);
  50   }
  51
  52   @Override
  53   public void flushLogs(E environment) {
  54     getDelegate().flushLogs(environment);
  55   }
  56
  57   @Override
  58   public List<Thread> getRequestThreads(E environment) {
  59     return getDelegate().getRequestThreads(environment);
  60   }
  61
  62   Delegate<E> getDelegateForThread() {
  63     return threadLocalDelegate.get();
  64   }
  65
  66   void setDelegateForThread(Delegate<E> delegate) {
  67     threadLocalDelegate.set(delegate);
  68   }
  69
  70   void clearThreadDelegate() {
  71     threadLocalDelegate.remove();
  72   }
  73
  74   Delegate<E> getGlobalDelegate() {
  75     return globalDelegate;
  76   }
  77 }