Avoid referencing gerrit specific Executor.

WorkQueue.Executor is a thin layer on top of
ScheduledThreadPoolExecutor. Since it is a class, rather than an
implementation, it is impossible to inject a wrapper around an
existing implementation.

This change is one step towards enabling this.

Change-Id: Id6b1d0fd10b5f8549cbc76a4867b3afb750aca02

gerrit-pgm/src/main/java/com/google/gerrit/pgm/http/jetty/ProjectQoSFilter.java

@@ -22,7 +22,6 @@ import static javax.servlet.http.HttpServletResponse.SC_SERVICE_UNAVAILABLE;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.config.GerritServerConfig;
 import com.google.gerrit.server.git.QueueProvider;
-import com.google.gerrit.server.git.WorkQueue;
 import com.google.gerrit.server.git.WorkQueue.CancelableRunnable;
 import com.google.gerrit.sshd.CommandExecutorQueueProvider;
 import com.google.inject.Inject;
@@ -30,6 +29,7 @@ import com.google.inject.Provider;
 import com.google.inject.Singleton;
 import com.google.inject.servlet.ServletModule;
 import java.io.IOException;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import javax.servlet.Filter;
@@ -102,7 +102,7 @@ public class ProjectQoSFilter implements Filter {
     final HttpServletResponse rsp = (HttpServletResponse) response;
     final Continuation cont = ContinuationSupport.getContinuation(req);
 
-    WorkQueue.Executor executor = getExecutor();
+    ScheduledThreadPoolExecutor executor = getExecutor();
 
     if (cont.isInitial()) {
       TaskThunk task = new TaskThunk(executor, cont, req);
@@ -136,7 +136,7 @@ public class ProjectQoSFilter implements Filter {
     }
   }
 
-  private WorkQueue.Executor getExecutor() {
+  private ScheduledThreadPoolExecutor getExecutor() {
     return queue.getQueue(user.get().getCapabilities().getQueueType());
   }
 
@@ -148,14 +148,17 @@ public class ProjectQoSFilter implements Filter {
 
   private final class TaskThunk implements CancelableRunnable, ContinuationListener {
 
-    private final WorkQueue.Executor executor;
+    private final ScheduledThreadPoolExecutor executor;
     private final Continuation cont;
     private final String name;
     private final Object lock = new Object();
     private boolean done;
     private Thread worker;
 
-    TaskThunk(WorkQueue.Executor executor, Continuation cont, HttpServletRequest req) {
+    TaskThunk(
+        ScheduledThreadPoolExecutor executor,
+        Continuation cont,
+        HttpServletRequest req) {
       this.executor = executor;
       this.cont = cont;
       this.name = generateName(req);

gerrit-server/src/main/java/com/google/gerrit/server/git/AsyncReceiveCommits.java

@@ -17,7 +17,6 @@ package com.google.gerrit.server.git;
 import com.google.gerrit.reviewdb.client.Project;
 import com.google.gerrit.server.config.ConfigUtil;
 import com.google.gerrit.server.config.GerritServerConfig;
-import com.google.gerrit.server.git.WorkQueue.Executor;
 import com.google.gerrit.server.project.ProjectControl;
 import com.google.gerrit.server.util.RequestScopePropagator;
 import com.google.inject.Inject;
@@ -30,6 +29,7 @@ import com.google.inject.name.Named;
 import java.io.OutputStream;
 import java.util.Collection;
 import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.lib.Repository;
@@ -125,7 +125,7 @@ public class AsyncReceiveCommits implements PreReceiveHook {
   }
 
   private final ReceiveCommits rc;
-  private final Executor executor;
+  private final ScheduledThreadPoolExecutor executor;
   private final RequestScopePropagator scopePropagator;
   private final MultiProgressMonitor progress;
   private final long timeoutMillis;
@@ -133,7 +133,7 @@ public class AsyncReceiveCommits implements PreReceiveHook {
   @Inject
   AsyncReceiveCommits(
       ReceiveCommits.Factory factory,
-      @ReceiveCommitsExecutor Executor executor,
+      @ReceiveCommitsExecutor ScheduledThreadPoolExecutor executor,
       RequestScopePropagator scopePropagator,
       @Named(TIMEOUT_NAME) long timeoutMillis,
       @Assisted ProjectControl projectControl,

gerrit-server/src/main/java/com/google/gerrit/server/git/QueueProvider.java

@@ -14,11 +14,13 @@
 
 package com.google.gerrit.server.git;
 
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+
 public interface QueueProvider {
   enum QueueType {
     INTERACTIVE,
     BATCH
   }
 
-  WorkQueue.Executor getQueue(QueueType type);
+  ScheduledThreadPoolExecutor getQueue(QueueType type);
 }

gerrit-server/src/main/java/com/google/gerrit/server/git/ReceiveCommitsExecutor.java

@@ -18,8 +18,9 @@ import static java.lang.annotation.RetentionPolicy.RUNTIME;
 
 import com.google.inject.BindingAnnotation;
 import java.lang.annotation.Retention;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 
-/** Marker on the global {@link WorkQueue.Executor} used by {@link ReceiveCommits}. */
+/** Marker on the global {@link ScheduledThreadPoolExecutor} used by {@link ReceiveCommits}. */
 @Retention(RUNTIME)
 @BindingAnnotation
 public @interface ReceiveCommitsExecutor {}

gerrit-server/src/main/java/com/google/gerrit/server/git/ReceiveCommitsExecutorModule.java

@@ -24,6 +24,7 @@ import com.google.inject.Provides;
 import com.google.inject.Singleton;
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.ExecutorService;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 import org.eclipse.jgit.lib.Config;
@@ -36,7 +37,7 @@ public class ReceiveCommitsExecutorModule extends AbstractModule {
   @Provides
   @Singleton
   @ReceiveCommitsExecutor
-  public WorkQueue.Executor createReceiveCommitsExecutor(
+  public ScheduledThreadPoolExecutor createReceiveCommitsExecutor(
       @GerritServerConfig Config config, WorkQueue queues) {
     int poolSize =
         config.getInt(

gerrit-server/src/main/java/com/google/gerrit/server/git/SendEmailExecutor.java

@@ -18,8 +18,9 @@ import static java.lang.annotation.RetentionPolicy.RUNTIME;
 
 import com.google.inject.BindingAnnotation;
 import java.lang.annotation.Retention;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 
-/** Marker on the global {@link WorkQueue.Executor} used to send email. */
+/** Marker on the global {@link ScheduledThreadPoolExecutor} used to send email. */
 @Retention(RUNTIME)
 @BindingAnnotation
 public @interface SendEmailExecutor {}

gerrit-server/src/main/java/com/google/gerrit/server/git/WorkQueue.java

@@ -82,7 +82,7 @@ public class WorkQueue {
         }
       };
 
-  private Executor defaultQueue;
+  private ScheduledThreadPoolExecutor defaultQueue;
   private int defaultQueueSize;
   private final IdGenerator idGenerator;
   private final CopyOnWriteArrayList<Executor> queues;
@@ -99,7 +99,7 @@ public class WorkQueue {
   }
 
   /** Get the default work queue, for miscellaneous tasks. */
-  public synchronized Executor getDefaultQueue() {
+  public synchronized ScheduledThreadPoolExecutor getDefaultQueue() {
     if (defaultQueue == null) {
       defaultQueue = createQueue(defaultQueueSize, "WorkQueue");
     }
@@ -107,7 +107,7 @@ public class WorkQueue {
   }
 
   /** Create a new executor queue. */
-  public Executor createQueue(int poolsize, String prefix) {
+  public ScheduledThreadPoolExecutor createQueue(int poolsize, String prefix) {
     final Executor r = new Executor(poolsize, prefix);
     r.setContinueExistingPeriodicTasksAfterShutdownPolicy(false);
     r.setExecuteExistingDelayedTasksAfterShutdownPolicy(true);
@@ -150,7 +150,7 @@ public class WorkQueue {
     return result;
   }
 
-  public Executor getExecutor(String queueName) {
+  public ScheduledThreadPoolExecutor getExecutor(String queueName) {
     for (Executor e : queues) {
       if (e.queueName.equals(queueName)) {
         return e;
@@ -175,7 +175,7 @@ public class WorkQueue {
   }
 
   /** An isolated queue. */
-  public class Executor extends ScheduledThreadPoolExecutor {
+  private class Executor extends ScheduledThreadPoolExecutor {
     private final ConcurrentHashMap<Integer, Task<?>> all;
     private final String queueName;
 
@@ -430,8 +430,8 @@ public class WorkQueue {
 
     @Override
     public String toString() {
-      //This is a workaround to be able to print a proper name when the task
+      // This is a workaround to be able to print a proper name when the task
-      //is wrapped into a TrustedListenableFutureTask.
+      // is wrapped into a TrustedListenableFutureTask.
       try {
         if (runnable
             .getClass()

gerrit-server/src/main/java/com/google/gerrit/server/util/RequestScopePropagator.java

@@ -29,6 +29,7 @@ import com.google.inject.Scope;
 import com.google.inject.servlet.ServletScopes;
 import java.util.concurrent.Callable;
 import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 
 /**
  * Base class for propagating request-scoped data between threads.
@@ -64,10 +65,9 @@ public abstract class RequestScopePropagator {
    * request state when the returned Callable is invoked. The method must be called in a request
    * scope and the returned Callable may only be invoked in a thread that is not already in a
    * request scope or is in the same request scope. The returned Callable will inherit toString()
-   * from the passed in Callable. A {@link com.google.gerrit.server.git.WorkQueue.Executor} does not
+   * from the passed in Callable. A {@link ScheduledThreadPoolExecutor} does not accept a Callable,
-   * accept a Callable, so there is no ProjectCallable implementation. Implementations of this
+   * so there is no ProjectCallable implementation. Implementations of this method must be
-   * method must be consistent with Guice's {@link ServletScopes#continueRequest(Callable,
+   * consistent with Guice's {@link ServletScopes#continueRequest(Callable, java.util.Map)}.
-   * java.util.Map)}.
    *
    * <p>There are some limitations:
    *

gerrit-sshd/src/main/java/com/google/gerrit/sshd/BaseCommand.java

@@ -28,7 +28,6 @@ import com.google.gerrit.server.DynamicOptions;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.RequestCleanup;
 import com.google.gerrit.server.git.ProjectRunnable;
-import com.google.gerrit.server.git.WorkQueue;
 import com.google.gerrit.server.git.WorkQueue.CancelableRunnable;
 import com.google.gerrit.server.permissions.GlobalPermission;
 import com.google.gerrit.server.permissions.PermissionBackend;
@@ -50,6 +49,7 @@ import java.io.PrintWriter;
 import java.io.StringWriter;
 import java.nio.charset.Charset;
 import java.util.concurrent.Future;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.concurrent.atomic.AtomicReference;
 import org.apache.sshd.common.SshException;
 import org.apache.sshd.server.Command;
@@ -85,7 +85,7 @@ public abstract class BaseCommand implements Command {
 
   @Inject private RequestCleanup cleanup;
 
-  @Inject @CommandExecutor private WorkQueue.Executor executor;
+  @Inject @CommandExecutor private ScheduledThreadPoolExecutor executor;
 
   @Inject private PermissionBackend permissionBackend;
   @Inject private CurrentUser user;

gerrit-sshd/src/main/java/com/google/gerrit/sshd/CommandExecutor.java

@@ -16,11 +16,11 @@ package com.google.gerrit.sshd;
 
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
 
-import com.google.gerrit.server.git.WorkQueue.Executor;
 import com.google.inject.BindingAnnotation;
 import java.lang.annotation.Retention;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 
-/** Marker on {@link Executor} used by SSH threads. */
+/** Marker on {@link ScheduledThreadPoolExecutor} used by SSH threads. */
 @Retention(RUNTIME)
 @BindingAnnotation
 public @interface CommandExecutor {}

gerrit-sshd/src/main/java/com/google/gerrit/sshd/CommandExecutorProvider.java

@@ -16,11 +16,11 @@ package com.google.gerrit.sshd;
 
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.git.QueueProvider;
-import com.google.gerrit.server.git.WorkQueue;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 
-class CommandExecutorProvider implements Provider<WorkQueue.Executor> {
+class CommandExecutorProvider implements Provider<ScheduledThreadPoolExecutor> {
 
   private final QueueProvider queues;
   private final CurrentUser user;
@@ -32,7 +32,7 @@ class CommandExecutorProvider implements Provider<WorkQueue.Executor> {
   }
 
   @Override
-  public WorkQueue.Executor get() {
+  public ScheduledThreadPoolExecutor get() {
     return queues.getQueue(user.getCapabilities().getQueueType());
   }
 }

gerrit-sshd/src/main/java/com/google/gerrit/sshd/CommandExecutorQueueProvider.java

@@ -19,6 +19,7 @@ import com.google.gerrit.server.config.ThreadSettingsConfig;
 import com.google.gerrit.server.git.QueueProvider;
 import com.google.gerrit.server.git.WorkQueue;
 import com.google.inject.Inject;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.concurrent.ThreadFactory;
 import org.eclipse.jgit.lib.Config;
 
@@ -26,8 +27,8 @@ public class CommandExecutorQueueProvider implements QueueProvider {
 
   private int poolSize;
   private final int batchThreads;
-  private final WorkQueue.Executor interactiveExecutor;
+  private final ScheduledThreadPoolExecutor interactiveExecutor;
-  private final WorkQueue.Executor batchExecutor;
+  private final ScheduledThreadPoolExecutor batchExecutor;
 
   @Inject
   public CommandExecutorQueueProvider(
@@ -51,7 +52,7 @@ public class CommandExecutorQueueProvider implements QueueProvider {
     setThreadFactory(interactiveExecutor);
   }
 
-  private void setThreadFactory(WorkQueue.Executor executor) {
+  private void setThreadFactory(ScheduledThreadPoolExecutor executor) {
     final ThreadFactory parent = executor.getThreadFactory();
     executor.setThreadFactory(
         new ThreadFactory() {
@@ -65,7 +66,7 @@ public class CommandExecutorQueueProvider implements QueueProvider {
   }
 
   @Override
-  public WorkQueue.Executor getQueue(QueueType type) {
+  public ScheduledThreadPoolExecutor getQueue(QueueType type) {
     switch (type) {
       case INTERACTIVE:
         return interactiveExecutor;

gerrit-sshd/src/main/java/com/google/gerrit/sshd/SshModule.java

@@ -26,7 +26,6 @@ import com.google.gerrit.server.config.GerritRequestModule;
 import com.google.gerrit.server.config.GerritServerConfig;
 import com.google.gerrit.server.git.AsyncReceiveCommits;
 import com.google.gerrit.server.git.QueueProvider;
-import com.google.gerrit.server.git.WorkQueue;
 import com.google.gerrit.server.plugins.ModuleGenerator;
 import com.google.gerrit.server.plugins.ReloadPluginListener;
 import com.google.gerrit.server.plugins.StartPluginListener;
@@ -39,6 +38,7 @@ import com.google.inject.servlet.RequestScoped;
 import java.net.SocketAddress;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import org.apache.sshd.server.CommandFactory;
 import org.apache.sshd.server.auth.gss.GSSAuthenticator;
 import org.apache.sshd.server.auth.pubkey.PublickeyAuthenticator;
@@ -77,7 +77,7 @@ public class SshModule extends LifecycleModule {
         .toInstance(new DispatchCommandProvider(Commands.CMD_ROOT));
     bind(CommandFactoryProvider.class);
     bind(CommandFactory.class).toProvider(CommandFactoryProvider.class);
-    bind(WorkQueue.Executor.class)
+    bind(ScheduledThreadPoolExecutor.class)
         .annotatedWith(StreamCommandExecutor.class)
         .toProvider(StreamCommandExecutorProvider.class)
         .in(SINGLETON);
@@ -126,7 +126,7 @@ public class SshModule extends LifecycleModule {
         .toProvider(SshRemotePeerProvider.class)
         .in(SshScope.REQUEST);
 
-    bind(WorkQueue.Executor.class)
+    bind(ScheduledThreadPoolExecutor.class)
         .annotatedWith(CommandExecutor.class)
         .toProvider(CommandExecutorProvider.class)
         .in(SshScope.REQUEST);

gerrit-sshd/src/main/java/com/google/gerrit/sshd/StreamCommandExecutor.java

@@ -16,11 +16,11 @@ package com.google.gerrit.sshd;
 
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
 
-import com.google.gerrit.server.git.WorkQueue.Executor;
 import com.google.inject.BindingAnnotation;
 import java.lang.annotation.Retention;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 
-/** Marker on {@link Executor} used by delayed event streaming. */
+/** Marker on {@link ScheduledThreadPoolExecutor} used by delayed event streaming. */
 @Retention(RUNTIME)
 @BindingAnnotation
 public @interface StreamCommandExecutor {}

gerrit-sshd/src/main/java/com/google/gerrit/sshd/StreamCommandExecutorProvider.java

@@ -18,10 +18,11 @@ import com.google.gerrit.server.config.GerritServerConfig;
 import com.google.gerrit.server.git.WorkQueue;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.concurrent.ThreadFactory;
 import org.eclipse.jgit.lib.Config;
 
-class StreamCommandExecutorProvider implements Provider<WorkQueue.Executor> {
+class StreamCommandExecutorProvider implements Provider<ScheduledThreadPoolExecutor> {
   private final int poolSize;
   private final WorkQueue queues;
 
@@ -33,8 +34,8 @@ class StreamCommandExecutorProvider implements Provider<WorkQueue.Executor> {
   }
 
   @Override
-  public WorkQueue.Executor get() {
+  public ScheduledThreadPoolExecutor get() {
-    final WorkQueue.Executor executor;
+    final ScheduledThreadPoolExecutor executor;
 
     executor = queues.createQueue(poolSize, "SSH-Stream-Worker");
 

gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/ShowQueue.java

@@ -38,6 +38,7 @@ import java.io.IOException;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.List;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import org.apache.sshd.server.Environment;
 import org.kohsuke.args4j.Option;
 
@@ -108,7 +109,7 @@ final class ShowQueue extends SshCommand {
     if (groupByQueue) {
       ListMultimap<String, TaskInfo> byQueue = byQueue(tasks);
       for (String queueName : byQueue.keySet()) {
-        WorkQueue.Executor e = workQueue.getExecutor(queueName);
+        ScheduledThreadPoolExecutor e = workQueue.getExecutor(queueName);
         stdout.print(String.format("Queue: %s\n", queueName));
         print(byQueue.get(queueName), now, viewAll, e.getCorePoolSize());
       }

gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/StreamEvents.java

@@ -29,7 +29,6 @@ import com.google.gerrit.server.events.Event;
 import com.google.gerrit.server.events.EventTypes;
 import com.google.gerrit.server.events.ProjectNameKeySerializer;
 import com.google.gerrit.server.events.SupplierSerializer;
-import com.google.gerrit.server.git.WorkQueue;
 import com.google.gerrit.server.git.WorkQueue.CancelableRunnable;
 import com.google.gerrit.sshd.BaseCommand;
 import com.google.gerrit.sshd.CommandMetaData;
@@ -43,6 +42,7 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.Future;
 import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import org.apache.sshd.server.Environment;
 import org.kohsuke.args4j.Option;
 import org.slf4j.Logger;
@@ -71,7 +71,7 @@ final class StreamEvents extends BaseCommand {
 
   @Inject private DynamicSet<UserScopedEventListener> eventListeners;
 
-  @Inject @StreamCommandExecutor private WorkQueue.Executor pool;
+  @Inject @StreamCommandExecutor private ScheduledThreadPoolExecutor pool;
 
   /** Queue of events to stream to the connected user. */
   private final LinkedBlockingQueue<Event> queue = new LinkedBlockingQueue<>(MAX_EVENTS);