[217020] Refactored ICommandControl interface to use a token to identify queued commands.

plugins/org.eclipse.dd.dsf.debug/src/org/eclipse/dd/dsf/debug/service/command/CommandCache.java

@@ -55,18 +55,20 @@ public class CommandCache implements ICommandListener
          */
         
         /** List of the request monitors associated with this command */
-        List<DataRequestMonitor<ICommandResult>> fCurrentRequestMonitors ; 
+        private final List<DataRequestMonitor<ICommandResult>> fCurrentRequestMonitors ; 
         
         /** Original command. Need for reference from Queue completion notification */
-        ICommand<ICommandResult> fCommand;                   
+        private final ICommand<ICommandResult> fCommand;                   
 
         /** Style of this command ( internal coalesced or not) */
-        CommandStyle fCmdStyle;
+        private final CommandStyle fCmdStyle;
         
         /** Command being processed for this command */
-        CommandInfo fCoalescedCmd;           
+        private CommandInfo fCoalescedCmd;           
 
-        public CommandInfo( CommandStyle cmdstyle, ICommand<ICommandResult> cmd, DataRequestMonitor<ICommandResult> rm ) {
+        private ICommandToken fToken;
+        
+        public CommandInfo(CommandStyle cmdstyle, ICommand<ICommandResult> cmd, DataRequestMonitor<ICommandResult> rm ) {
             fCmdStyle = cmdstyle;
             fCommand = cmd;
             fCurrentRequestMonitors = new LinkedList<DataRequestMonitor<ICommandResult>>();
@@ -219,7 +221,7 @@ public class CommandCache implements ICommandListener
                  *  does not continue to process it.
                  */
                 fPendingQCommandsNotYetSent.remove(currentUnsentEntry);
-                fCommandControl.removeCommand(unsentCommand);
+                fCommandControl.removeCommand(currentUnsentEntry.fToken);
               
                 return( coalescedCmdInfo );
             }
@@ -316,7 +318,7 @@ public class CommandCache implements ICommandListener
         final CommandInfo finalCachedCmd = cachedCmd;
         fPendingQCommandsNotYetSent.add(finalCachedCmd);
         
-        fCommandControl.queueCommand(
+        finalCachedCmd.fToken = fCommandControl.queueCommand(
             finalCachedCmd.getCommand(), 
             new DataRequestMonitor<ICommandResult>(fSession.getExecutor(), null) { 
                 @Override
@@ -476,7 +478,7 @@ public class CommandCache implements ICommandListener
     	fCachedContexts.clear();
     }
 
-    public void commandRemoved(ICommand<? extends ICommandResult> command) {
+    public void commandRemoved(ICommandToken token) {
         /*
          *  Do nothing. 
          */
@@ -486,7 +488,7 @@ public class CommandCache implements ICommandListener
      * (non-Javadoc)
      * @see org.eclipse.dd.dsf.mi.service.control.IDebuggerControl.ICommandListener#commandQueued(org.eclipse.dd.dsf.mi.core.command.ICommand)
      */
-    public void commandQueued(ICommand<? extends ICommandResult> command) {
+    public void commandQueued(ICommandToken token) {
         /*
          *  Do nothing. 
          */
@@ -496,7 +498,7 @@ public class CommandCache implements ICommandListener
      * (non-Javadoc)
      * @see org.eclipse.dd.dsf.mi.service.control.IDebuggerControl.ICommandListener#commandDone(org.eclipse.dd.dsf.mi.core.command.ICommand, org.eclipse.dd.dsf.mi.core.command.ICommandResult)
      */
-    public void commandDone(ICommand<? extends ICommandResult> command, ICommandResult result) {
+    public void commandDone(ICommandToken token, ICommandResult result) {
         /*
          *  We handle the done with a runnable where we initiated the command
          *  so there is nothing to do here.
@@ -511,11 +513,11 @@ public class CommandCache implements ICommandListener
      * (non-Javadoc)
      * @see org.eclipse.dd.dsf.mi.service.control.IDebuggerControl.ICommandListener#commandSent(org.eclipse.dd.dsf.mi.core.command.ICommand)
      */
-    public void commandSent(ICommand<? extends ICommandResult> command) {
+    public void commandSent(ICommandToken token) {
         
         // Cast the generic ?'s to concrete types in the cache implementation.
         @SuppressWarnings("unchecked")
-        ICommand<ICommandResult> genericCommand = (ICommand<ICommandResult>)command;
+        ICommand<ICommandResult> genericCommand = (ICommand<ICommandResult>)token.getCommand();
         
         CommandInfo cachedCmd = new CommandInfo( CommandStyle.NONCOALESCED, genericCommand, null) ;
         

plugins/org.eclipse.dd.dsf.debug/src/org/eclipse/dd/dsf/debug/service/command/ICommandControl.java

@@ -25,7 +25,7 @@ public interface ICommandControl {
      * @param rm Request completion monitor
      * @return None
      */
-    <V extends ICommandResult> void queueCommand(ICommand<V> command, DataRequestMonitor<V> rm);
+    <V extends ICommandResult> ICommandToken queueCommand(ICommand<V> command, DataRequestMonitor<V> rm);
     
     /**
      * Removes the specified command from the processor queue.
@@ -33,17 +33,7 @@ public interface ICommandControl {
      * @param command Specific command to be removed
      * @return None
      */
-    void removeCommand(ICommand<? extends ICommandResult> command);
+    void removeCommand(ICommandToken token);
-    
-    /**
-     * Attempts to cancel and already sent command. Some versions
-     * of GDB/MI implement control commands which allow this. The
-     * GDB/MI standard does not currently allow for this.
-     *   
-     * @param command Specific command to be removed
-     * @return None
-     */
-    void cancelCommand(ICommand<? extends ICommandResult> command);
     
     /**
 	 * Adds a notification handler for the Command processor.

plugins/org.eclipse.dd.dsf.debug/src/org/eclipse/dd/dsf/debug/service/command/ICommandListener.java

@@ -18,7 +18,7 @@ public interface ICommandListener {
 	 * @return None
 	 * @param command Command which has been added to the Queue
  	 */
-	public void commandQueued(ICommand<? extends ICommandResult> command);
+	public void commandQueued(ICommandToken token);
 	
 	/**
      * Notification that the given command was sent to the debugger. At this 
@@ -29,7 +29,7 @@ public interface ICommandListener {
      * @return None
      * @param command
      */
-    public void commandSent(ICommand<? extends ICommandResult> command);
+    public void commandSent(ICommandToken token);
 
 	/**
 	 * Notifies that the specified command has been removed from the 
@@ -42,7 +42,7 @@ public interface ICommandListener {
 	 * @return None
 	 * @param Command which has been sent to the backend
 	 */
-	public void commandRemoved(ICommand<? extends ICommandResult> command);
+	public void commandRemoved(ICommandToken token);
     
 	/**
 	 * Notifies that the specified command has been completed.
@@ -50,5 +50,5 @@ public interface ICommandListener {
 	 * @return None
 	 * @param Command which has been sent to the backend
 	 */
-	public void commandDone(ICommand<? extends ICommandResult> command, ICommandResult result);
+	public void commandDone(ICommandToken token, ICommandResult result);
 }

plugins/org.eclipse.dd.dsf.debug/src/org/eclipse/dd/dsf/debug/service/command/ICommandToken.java

@@ -0,0 +1,23 @@
+/*******************************************************************************
+ * Copyright (c) 2008 Wind River Systems and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * 
+ * Contributors:
+ *     Wind River Systems - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.dd.dsf.debug.service.command;
+
+/**
+ * Token returned by ICommandControl.queueCommand().  This token can be used
+ * to uniquely identify a command when calling ICommandControl.removeCommand()
+ * or when implementing the ICommandListener listener methods.
+ */
+public interface ICommandToken {
+    /**
+     * Returns the command that this was created for.
+     */
+    public ICommand<? extends ICommandResult> getCommand();
+}

plugins/org.eclipse.dd.examples.pda/src/org/eclipse/dd/examples/pda/service/PDACommandControl.java

@@ -27,6 +27,7 @@ import org.eclipse.dd.dsf.debug.service.command.ICommand;
 import org.eclipse.dd.dsf.debug.service.command.ICommandControl;
 import org.eclipse.dd.dsf.debug.service.command.ICommandListener;
 import org.eclipse.dd.dsf.debug.service.command.ICommandResult;
+import org.eclipse.dd.dsf.debug.service.command.ICommandToken;
 import org.eclipse.dd.dsf.debug.service.command.IEventListener;
 import org.eclipse.dd.dsf.service.AbstractDsfService;
 import org.eclipse.dd.dsf.service.DsfSession;
@@ -44,10 +45,12 @@ public class PDACommandControl extends AbstractDsfService implements ICommandCon
 
     // Structure used to store command information in services internal queues.
     private static class CommandHandle {
+        final private ICommandToken fToken;
         final private AbstractPDACommand<PDACommandResult> fCommand;
         final private DataRequestMonitor<PDACommandResult> fRequestMonitor;
         
-        CommandHandle(AbstractPDACommand<PDACommandResult> c, DataRequestMonitor<PDACommandResult> rm) {
+        CommandHandle(ICommandToken token, AbstractPDACommand<PDACommandResult> c, DataRequestMonitor<PDACommandResult> rm) {
+            fToken = token;
             fCommand = c; 
             fRequestMonitor = rm;
         }
@@ -334,7 +337,13 @@ public class PDACommandControl extends AbstractDsfService implements ICommandCon
         
     }
     
-    public <V extends ICommandResult> void queueCommand(ICommand<V> command, DataRequestMonitor<V> rm) {
+    public <V extends ICommandResult> ICommandToken queueCommand(final ICommand<V> command, DataRequestMonitor<V> rm) {
+        ICommandToken token = new ICommandToken() {
+            public ICommand<?> getCommand() {
+                return command;
+            }
+        };
+
         if (command instanceof AbstractPDACommand<?>) {
             // Cast from command with "<V extends ICommandResult>" to a more concrete
             // type to use internally in the command control.
@@ -346,9 +355,9 @@ public class PDACommandControl extends AbstractDsfService implements ICommandCon
             DataRequestMonitor<PDACommandResult> pdaRM = (DataRequestMonitor<PDACommandResult>)rm;
 
             // Add the command to the queue and notify command listeners.
-            fCommandQueue.add( new CommandHandle(pdaCommand, pdaRM) );
+            fCommandQueue.add( new CommandHandle(token, pdaCommand, pdaRM) );
             for (ICommandListener listener : fCommandListeners) {
-                listener.commandQueued(command);
+                listener.commandQueued(token);
             }
             
             // In a separate dispatch cycle.  This allows command listeners to respond to the 
@@ -358,25 +367,20 @@ public class PDACommandControl extends AbstractDsfService implements ICommandCon
                     processQueues();
                 }
             });
-            
         } else {
             PDAPlugin.failRequest(rm, INTERNAL_ERROR, "Unrecognized command: " + command);
         }
+        return token;
     }
 
-    public void cancelCommand(ICommand<? extends ICommandResult> command) {
+    public void removeCommand(ICommandToken token) {
-        // This debugger is unable of canceling commands once they have 
-        // been sent.
-    }
-
-    public void removeCommand(ICommand<? extends ICommandResult> command) {
         // Removes given command from the queue and notify the listeners
         for (Iterator<CommandHandle> itr = fCommandQueue.iterator(); itr.hasNext();) {
             CommandHandle handle = itr.next();
-            if (command.equals(handle.fCommand)) {
+            if (token.equals(handle.fToken)) {
                 itr.remove();
                 for (ICommandListener listener : fCommandListeners) {
-                    listener.commandRemoved(command);
+                    listener.commandRemoved(token);
                 }                
             }
         }
@@ -414,7 +418,7 @@ public class PDACommandControl extends AbstractDsfService implements ICommandCon
 
         // Notify listeners of the response
         for (ICommandListener listener : fCommandListeners) {
-            listener.commandDone(handle.fCommand, result);
+            listener.commandDone(handle.fToken, result);
         }
         
         // Process next command in queue.
@@ -431,7 +435,7 @@ public class PDACommandControl extends AbstractDsfService implements ICommandCon
 
         // Notify listeners also.
         for (ICommandListener listener : fCommandListeners) {
-            listener.commandDone(handle.fCommand, null);
+            listener.commandDone(handle.fToken, null);
         }
     }
 
@@ -462,7 +466,7 @@ public class PDACommandControl extends AbstractDsfService implements ICommandCon
             fTxCommands.add(handle);
             PDAPlugin.debug("C: " + handle.fCommand.getRequest());
             for (ICommandListener listener : fCommandListeners) {
-                listener.commandSent(handle.fCommand);
+                listener.commandSent(handle.fToken);
             }            
         }
     }

plugins/org.eclipse.dd.examples.pda/src/org/eclipse/dd/tests/pda/service/command/BasicTests.java

@@ -23,6 +23,7 @@ import org.eclipse.dd.dsf.concurrent.Query;
 import org.eclipse.dd.dsf.debug.service.command.ICommand;
 import org.eclipse.dd.dsf.debug.service.command.ICommandListener;
 import org.eclipse.dd.dsf.debug.service.command.ICommandResult;
+import org.eclipse.dd.dsf.debug.service.command.ICommandToken;
 import org.eclipse.dd.examples.pda.service.commands.PDACommandResult;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -53,17 +54,17 @@ public class BasicTests extends CommandControlTestsBase {
             List<CommandInfo> fRemovedCommands = new LinkedList<CommandInfo>(); 
             List<CommandInfo> fSentCommands = new LinkedList<CommandInfo>(); 
             
-            public void commandDone(ICommand<? extends ICommandResult> command, ICommandResult result) { 
+            public void commandDone(ICommandToken token, ICommandResult result) { 
-                fDoneCommands.add(new CommandInfo(command, result));
+                fDoneCommands.add(new CommandInfo(token.getCommand(), result));
             }
-            public void commandQueued(ICommand<? extends ICommandResult> command) {
+            public void commandQueued(ICommandToken token) {
-                fQueuedCommands.add(new CommandInfo(command, null));
+                fQueuedCommands.add(new CommandInfo(token.getCommand(), null));
             }
-            public void commandRemoved(ICommand<? extends ICommandResult> command) {
+            public void commandRemoved(ICommandToken token) {
-                fRemovedCommands.add(new CommandInfo(command, null));
+                fRemovedCommands.add(new CommandInfo(token.getCommand(), null));
             }
-            public void commandSent(ICommand<? extends ICommandResult> command) {
+            public void commandSent(ICommandToken token) {
-                fSentCommands.add(new CommandInfo(command, null));
+                fSentCommands.add(new CommandInfo(token.getCommand(), null));
             }
             
             void reset() {
@@ -106,7 +107,7 @@ public class BasicTests extends CommandControlTestsBase {
         Query<Object> queueRemoveCommandQuery = new Query<Object>() {
             @Override
             protected void execute(DataRequestMonitor<Object> rm) {
-                fCommandControl.queueCommand(
+                ICommandToken token = fCommandControl.queueCommand(
                     testCommand, 
                     new DataRequestMonitor<PDACommandResult>(fExecutor, null) {
                         @Override
@@ -114,7 +115,7 @@ public class BasicTests extends CommandControlTestsBase {
                             Assert.fail("This command should never have been executed.");
                         }
                     });
-                fCommandControl.removeCommand(testCommand);
+                fCommandControl.removeCommand(token);
 
                 rm.setData(new Object());
                 rm.done();

plugins/org.eclipse.dd.mi/src/org/eclipse/dd/mi/service/MIVariableManager.java

@@ -40,6 +40,7 @@ import org.eclipse.dd.dsf.debug.service.command.ICommand;
 import org.eclipse.dd.dsf.debug.service.command.ICommandControl;
 import org.eclipse.dd.dsf.debug.service.command.ICommandListener;
 import org.eclipse.dd.dsf.debug.service.command.ICommandResult;
+import org.eclipse.dd.dsf.debug.service.command.ICommandToken;
 import org.eclipse.dd.dsf.debug.service.command.IEventListener;
 import org.eclipse.dd.dsf.service.DsfServiceEventHandler;
 import org.eclipse.dd.dsf.service.DsfServicesTracker;
@@ -1487,13 +1488,19 @@ public class MIVariableManager implements ICommandControl {
 				});
 	}
 
-    public <V extends ICommandResult> void queueCommand(final ICommand<V> command, DataRequestMonitor<V> rm) {
+    public <V extends ICommandResult> ICommandToken queueCommand(final ICommand<V> command, DataRequestMonitor<V> rm) {
+    	
+        final ICommandToken token = new ICommandToken() {
+            public ICommand<? extends ICommandResult> getCommand() {
+                return command;
+            }
+        };
         
     	// The MIVariableManager does not buffer commands itself, but sends them directly to the real
     	// MICommandControl service.  Therefore, we must immediately tell our calling cache that the command
     	// has been sent, since we can never cancel it.  Note that this removes any option of coalescing, 
     	// but coalescing was not applicable to variableObjects anyway.
-    	processCommandSent(command);
+    	processCommandSent(token);
     	
     	if (command instanceof ExprMetaGetVar) {
             @SuppressWarnings("unchecked")            
@@ -1512,6 +1519,7 @@ public class MIVariableManager implements ICommandControl {
             								getData().getType(),
             								!getData().isComplex()));
             				drm.done();
+            				processCommandDone(token, drm.getData());
             			}
             		});
         } else if (command instanceof ExprMetaGetAttributes) {
@@ -1530,6 +1538,7 @@ public class MIVariableManager implements ICommandControl {
                                         protected void handleSuccess() {
                                             drm.setData(new ExprMetaGetAttributesInfo(getData()));
                                             drm.done();
+                                            processCommandDone(token, drm.getData());
                                         }
                                     }); 
                         }
@@ -1555,6 +1564,7 @@ public class MIVariableManager implements ICommandControl {
     	                    				drm.setData(
     	                    						new ExprMetaGetValueInfo(getData().getFormattedValue()));
     	                    				drm.done();
+    	                                    processCommandDone(token, drm.getData());
     	                    			}
     	                    		});
     	                }
@@ -1577,6 +1587,7 @@ public class MIVariableManager implements ICommandControl {
     									protected void handleSuccess() {
     										drm.setData(new ExprMetaGetChildrenInfo(getData()));
     										drm.done();
+    			                            processCommandDone(token, drm.getData());
     									}
     								});
     					}
@@ -1598,6 +1609,7 @@ public class MIVariableManager implements ICommandControl {
     									protected void handleSuccess() {
     										drm.setData(new ExprMetaGetChildCountInfo(getData()));
     										drm.done();
+    			                            processCommandDone(token, drm.getData());
     									}
     								}); 
     					}
@@ -1611,6 +1623,7 @@ public class MIVariableManager implements ICommandControl {
 					"Unexpected Expression Meta command", null)); //$NON-NLS-1$
 			rm.done();
     	}
+    	return token;
     }
     
     /*
@@ -1621,7 +1634,7 @@ public class MIVariableManager implements ICommandControl {
      * (non-Javadoc)
      * @see org.eclipse.dd.mi.service.command.IDebuggerControl#removeCommand(org.eclipse.dd.mi.service.command.commands.ICommand)
      */
-    public void removeCommand(ICommand<? extends ICommandResult> command) {
+    public void removeCommand(ICommandToken token) {
     	// It is impossible to remove a command from the MIVariableManager.
     	// This should never be called, if we did things right.
     	assert false;
@@ -1637,16 +1650,21 @@ public class MIVariableManager implements ICommandControl {
      * (non-Javadoc)
      * @see org.eclipse.dd.mi.service.command.IDebuggerControl#cancelCommand(org.eclipse.dd.mi.service.command.commands.ICommand)
      */
-    public void cancelCommand(ICommand<? extends ICommandResult> command) {}
     public void addCommandListener(ICommandListener processor) { fCommandProcessors.add(processor); }
     public void removeCommandListener(ICommandListener processor) { fCommandProcessors.remove(processor); }    
     public void addEventListener(IEventListener processor) {}
     public void removeEventListener(IEventListener processor) {}
 
     
-    private void processCommandSent(ICommand<?> command) {
+    private void processCommandSent(ICommandToken token) {
         for (ICommandListener processor : fCommandProcessors) {
-            processor.commandSent(command);
+            processor.commandSent(token);
+        }
+    }
+
+    private void processCommandDone(ICommandToken token, ICommandResult result) {
+        for (ICommandListener processor : fCommandProcessors) {
+            processor.commandDone(token, result);
         }
     }
     
@@ -1679,5 +1697,4 @@ public class MIVariableManager implements ICommandControl {
     	// The views will fully refresh on a MemoryChangedEvent
     	markAllOutOfDate();
     }
-
 }

plugins/org.eclipse.dd.mi/src/org/eclipse/dd/mi/service/command/AbstractCLIProcess.java

@@ -30,6 +30,7 @@ import org.eclipse.dd.dsf.datamodel.IDMContext;
 import org.eclipse.dd.dsf.debug.service.command.ICommand;
 import org.eclipse.dd.dsf.debug.service.command.ICommandListener;
 import org.eclipse.dd.dsf.debug.service.command.ICommandResult;
+import org.eclipse.dd.dsf.debug.service.command.ICommandToken;
 import org.eclipse.dd.dsf.debug.service.command.IEventListener;
 import org.eclipse.dd.dsf.service.DsfSession;
 import org.eclipse.dd.mi.internal.MIPlugin;
@@ -204,11 +205,12 @@ public abstract class AbstractCLIProcess extends Process
         }
     }
     
-    public void commandQueued(ICommand<? extends ICommandResult> command) {
+    public void commandQueued(ICommandToken token) {
             // Ignore
     }
 
-    public void commandSent(ICommand<? extends ICommandResult> command) {
+    public void commandSent(ICommandToken token) {
+        ICommand<?> command = token.getCommand();
         // Check if the command is a CLI command and if it did not originate from this class.
         if (command instanceof CLICommand<?> &&
             !(command instanceof ProcessCLICommand || command instanceof ProcessMIInterpreterExecConsole)) 
@@ -217,12 +219,13 @@ public abstract class AbstractCLIProcess extends Process
         }
     }
 
-    public void commandRemoved(ICommand<? extends ICommandResult> command) {
+    public void commandRemoved(ICommandToken token) {
             // Ignore
     }
 
-    public void commandDone(ICommand<? extends ICommandResult> command, ICommandResult result) {
+    public void commandDone(ICommandToken token, ICommandResult result) {
-    	if (command instanceof CLICommand<?> &&
+        ICommand<?> command = token.getCommand();
+    	if (token.getCommand() instanceof CLICommand<?> &&
     			!(command instanceof ProcessCLICommand || command instanceof ProcessMIInterpreterExecConsole)) 
         {
             fSuppressConsoleOutputCounter--;

plugins/org.eclipse.dd.mi/src/org/eclipse/dd/mi/service/command/AbstractMIControl.java

@@ -36,6 +36,7 @@ import org.eclipse.dd.dsf.debug.service.command.ICommand;
 import org.eclipse.dd.dsf.debug.service.command.ICommandControl;
 import org.eclipse.dd.dsf.debug.service.command.ICommandListener;
 import org.eclipse.dd.dsf.debug.service.command.ICommandResult;
+import org.eclipse.dd.dsf.debug.service.command.ICommandToken;
 import org.eclipse.dd.dsf.debug.service.command.IEventListener;
 import org.eclipse.dd.dsf.service.AbstractDsfService;
 import org.eclipse.dd.dsf.service.DsfSession;
@@ -182,14 +183,7 @@ public abstract class AbstractMIControl extends AbstractDsfService
      * @see org.eclipse.dd.dsf.debug.service.command.ICommandControl#addCommand(org.eclipse.dd.dsf.debug.service.command.ICommand, org.eclipse.dd.dsf.concurrent.RequestMonitor)
      */
     
-    public <V extends ICommandResult> void queueCommand(ICommand<V> command, DataRequestMonitor<V> rm) {
+    public <V extends ICommandResult> ICommandToken queueCommand(final ICommand<V> command, DataRequestMonitor<V> rm) {
-
-        // If the command control stopped processing commands, just return an error immediately. 
-        if (fStoppedCommandProcessing) {
-            rm.setStatus(genStatus("Connection is shut down")); //$NON-NLS-1$
-            rm.done();
-            return;
-        }
 
         // Cast the command to MI Command type.  This will cause a cast exception to be 
         // thrown if the client did not give an MI command as an argument.
@@ -203,7 +197,11 @@ public abstract class AbstractMIControl extends AbstractDsfService
 
         final CommandHandle handle = new CommandHandle(miCommand, miDone);
 
-        if ( fRxCommands.size() > 3 ) {
+        // If the command control stopped processing commands, just return an error immediately. 
+        if (fStoppedCommandProcessing) {
+            rm.setStatus(genStatus("Connection is shut down")); //$NON-NLS-1$
+            rm.done();
+        } else if ( fRxCommands.size() > 3 ) {
         	
         	/*
         	 *  We  only allow three  outstanding commands  to be on the wire  to the backend
@@ -238,7 +236,7 @@ public abstract class AbstractMIControl extends AbstractDsfService
             		CommandHandle cmdHandle = new CommandHandle(
             		    new MIThreadSelect(handle.fCommand.getContext(), fCurrentThreadId), null);
             		fTxCommands.add(cmdHandle);
-            		MIPlugin.debug(MIPlugin.getDebugTime() + " " + cmdHandle.getToken() + cmdHandle.getCommand()); //$NON-NLS-1$
+            		MIPlugin.debug(MIPlugin.getDebugTime() + " " + cmdHandle.getTokenId() + cmdHandle.getCommand()); //$NON-NLS-1$
             	}
 
             	// Before the command is sent, Check the Stack level and send it to 
@@ -251,12 +249,13 @@ public abstract class AbstractMIControl extends AbstractDsfService
             		CommandHandle cmdHandle = new CommandHandle(
             		    new MIStackSelectFrame(handle.fCommand.getContext(), fCurrentStackLevel), null);
             		fTxCommands.add(cmdHandle);
-            		MIPlugin.debug(MIPlugin.getDebugTime() + " " + cmdHandle.getToken() + cmdHandle.getCommand()); //$NON-NLS-1$
+            		MIPlugin.debug(MIPlugin.getDebugTime() + " " + cmdHandle.getTokenId() + cmdHandle.getCommand()); //$NON-NLS-1$
             	}
                	fTxCommands.add(handle);
             }
         }
         
+        return handle;
     }
     
     /*
@@ -267,12 +266,12 @@ public abstract class AbstractMIControl extends AbstractDsfService
      * (non-Javadoc)
      * @see org.eclipse.dd.mi.service.command.IDebuggerControl#removeCommand(org.eclipse.dd.mi.service.command.commands.ICommand)
      */
-    public void removeCommand(ICommand<? extends ICommandResult> command) {
+    public void removeCommand(ICommandToken token) {
     	
     	synchronized(fCommandQueue) {
     		
     		for ( CommandHandle handle : fCommandQueue ) {
-    			if ( handle.getCommand().equals(command)) {
+    			if ( handle.equals(token)) {
     				fCommandQueue.remove(handle);
     				
     				final CommandHandle finalHandle = handle;
@@ -287,18 +286,6 @@ public abstract class AbstractMIControl extends AbstractDsfService
     	}
     }
    
-    /*
-     *  This command allows the user to try and cancel commands  which have been handed off to the 
-     *  backend. Some backends support this with extended GDB/MI commands. If the support is there
-     *  then we will attempt it.  Because of the bidirectional nature of the GDB/MI command stream
-     *  there is no guarantee that this will work. The response to the command could be on its way
-     *  back when the cancel command is being issued.
-     *  
-     * (non-Javadoc)
-     * @see org.eclipse.dd.mi.service.command.IDebuggerControl#cancelCommand(org.eclipse.dd.mi.service.command.commands.ICommand)
-     */
-    public void  cancelCommand(ICommand<? extends ICommandResult> command) {}
-    
     /*
      *  Allows a user ( typically a cache manager ) to sign up a listener to monitor command queue
      *  activity.
@@ -339,19 +326,19 @@ public abstract class AbstractMIControl extends AbstractDsfService
 
     private void processCommandQueued(CommandHandle commandHandle) {
         for (ICommandListener processor : fCommandProcessors) {
-            processor.commandQueued(commandHandle.getCommand());
+            processor.commandQueued(commandHandle);
         }
     }
     private void processCommandRemoved(CommandHandle commandHandle) {
         for (ICommandListener processor : fCommandProcessors) {
-            processor.commandRemoved(commandHandle.getCommand());
+            processor.commandRemoved(commandHandle);
         }
     }
     
     private void processCommandSent(CommandHandle commandHandle) {
-        MIPlugin.debug(MIPlugin.getDebugTime() + " " + commandHandle.getToken() + commandHandle.getCommand()); //$NON-NLS-1$
+        MIPlugin.debug(MIPlugin.getDebugTime() + " " + commandHandle.getTokenId() + commandHandle.getCommand()); //$NON-NLS-1$
         for (ICommandListener processor : fCommandProcessors) {
-            processor.commandSent(commandHandle.getCommand());
+            processor.commandSent(commandHandle);
         }
     }
 
@@ -374,7 +361,7 @@ public abstract class AbstractMIControl extends AbstractDsfService
          *  Tell the listeners we have completed this one.
          */
         for (ICommandListener processor : fCommandProcessors) {
-            processor.commandDone(commandHandle == null ? null : commandHandle.getCommand(), result);
+            processor.commandDone(commandHandle, result);
         }
     }
     
@@ -389,14 +376,13 @@ public abstract class AbstractMIControl extends AbstractDsfService
 	 * A global counter for all command, the token will be use to identify uniquely a command.
 	 * Unless the value wraps around which is unlikely.
 	 */
+    private int fTokenIdCounter = 0 ;
     
-    private static int globalCounter = 0 ;
+	private int getNewTokenId() {
-    
+		int count = ++fTokenIdCounter;
-	private static synchronized int getUniqToken() {
-		int count = ++globalCounter;
 		// If we ever wrap around.
 		if (count <= 0) {
-			count = globalCounter = 1;
+			count = fTokenIdCounter = 1;
 		}
 		return count;
 	}
@@ -406,7 +392,7 @@ public abstract class AbstractMIControl extends AbstractDsfService
 	 *  individual request.
 	 */
     
-    public static class CommandHandle {
+    private class CommandHandle implements ICommandToken {
 
         private MICommand<MIInfo> fCommand;
         private DataRequestMonitor<MIInfo> fRequestMonitor;
@@ -415,12 +401,13 @@ public abstract class AbstractMIControl extends AbstractDsfService
         CommandHandle(MICommand<MIInfo> c, DataRequestMonitor<MIInfo> d) {
             fCommand = c; 
             fRequestMonitor = d;
-            fTokenId = getUniqToken() ;
+            fTokenId = getNewTokenId() ;
         }
         
         public MICommand<MIInfo> getCommand() { return fCommand; }
         public DataRequestMonitor<MIInfo> getRequestMonitor() { return fRequestMonitor; }
-        public Integer getToken() { return fTokenId; }
+        public Integer getTokenId() { return fTokenId; }
+        
         //public String getThreadId() { return null; } 
         public Integer getStackFrameId() {
         	IFrameDMContext frameCtx = DMContexts.getAncestorOfType(fCommand.getContext(), IFrameDMContext.class);
@@ -477,14 +464,14 @@ public abstract class AbstractMIControl extends AbstractDsfService
                     /*
                      *  We note that this is an outstanding request at this point.
                      */
-                    fRxCommands.put(commandHandle.getToken(), commandHandle);
+                    fRxCommands.put(commandHandle.getTokenId(), commandHandle);
                 }
                 
                 /*
                  *   Construct the new command and push this command out the pipeline.
                  */
                 
-                String str = commandHandle.getToken() + commandHandle.getCommand().constructCommand();
+                String str = commandHandle.getTokenId() + commandHandle.getCommand().constructCommand();
                 
                 try {
                     if (fOutputStream != null) {

plugins/org.eclipse.dd.mi/src/org/eclipse/dd/mi/service/command/CLIEventProcessor.java

@@ -24,9 +24,9 @@ import org.eclipse.dd.dsf.datamodel.IDMContext;
 import org.eclipse.dd.dsf.debug.service.IBreakpoints.IBreakpointsTargetDMContext;
 import org.eclipse.dd.dsf.debug.service.IRunControl.IContainerDMContext;
 import org.eclipse.dd.dsf.debug.service.ISignals.ISignalsDMContext;
-import org.eclipse.dd.dsf.debug.service.command.ICommand;
 import org.eclipse.dd.dsf.debug.service.command.ICommandListener;
 import org.eclipse.dd.dsf.debug.service.command.ICommandResult;
+import org.eclipse.dd.dsf.debug.service.command.ICommandToken;
 import org.eclipse.dd.dsf.debug.service.command.IEventListener;
 import org.eclipse.dd.mi.service.command.commands.CLICommand;
 import org.eclipse.dd.mi.service.command.commands.MIInterpreterExecConsole;
@@ -73,30 +73,30 @@ public class CLIEventProcessor
         fCommandControl.removeEventListener(this);        
     }
 
-    public void commandSent(ICommand<? extends ICommandResult> command) {
+    public void commandSent(ICommandToken token) {
-        if (command instanceof CLICommand<?>) {
+        if (token.getCommand() instanceof CLICommand<?>) {
-            processStateChanges( (CLICommand<?>)command );
+            processStateChanges( (CLICommand<?>)token.getCommand() );
         }
-        else if (command instanceof MIInterpreterExecConsole<?>) {
+        else if (token.getCommand() instanceof MIInterpreterExecConsole<?>) {
-            processStateChanges( (MIInterpreterExecConsole<?>)command );
+            processStateChanges( (MIInterpreterExecConsole<?>)token.getCommand() );
         }
     }
     
-    public void commandDone(ICommand<? extends ICommandResult> command, ICommandResult result) {
+    public void commandDone(ICommandToken token, ICommandResult result) {
-        if (command instanceof CLICommand<?>) {
+        if (token.getCommand() instanceof CLICommand<?>) {
-            processSettingChanges( (CLICommand<?>)command );
+            processSettingChanges( (CLICommand<?>)token.getCommand() );
         }
-        else if (command instanceof MIInterpreterExecConsole<?>) {
+        else if (token.getCommand() instanceof MIInterpreterExecConsole<?>) {
-            processSettingChanges( (MIInterpreterExecConsole<?>)command );
+            processSettingChanges( (MIInterpreterExecConsole<?>)token.getCommand() );
         }
         fEventList.clear();
     }
     
-    public void commandQueued(ICommand<? extends ICommandResult> command) {
+    public void commandQueued(ICommandToken token) {
         // No action 
     }
     
-    public void commandRemoved(ICommand<? extends ICommandResult> command) {
+    public void commandRemoved(ICommandToken token) {
         // No action 
     }
     

plugins/org.eclipse.dd.mi/src/org/eclipse/dd/mi/service/command/MIInferiorProcess.java

@@ -32,9 +32,9 @@ import org.eclipse.dd.dsf.concurrent.DsfRunnable;
 import org.eclipse.dd.dsf.concurrent.IDsfStatusConstants;
 import org.eclipse.dd.dsf.concurrent.ImmediateExecutor;
 import org.eclipse.dd.dsf.concurrent.Query;
-import org.eclipse.dd.dsf.debug.service.command.ICommand;
 import org.eclipse.dd.dsf.debug.service.command.ICommandListener;
 import org.eclipse.dd.dsf.debug.service.command.ICommandResult;
+import org.eclipse.dd.dsf.debug.service.command.ICommandToken;
 import org.eclipse.dd.dsf.debug.service.command.IEventListener;
 import org.eclipse.dd.dsf.service.DsfSession;
 import org.eclipse.dd.mi.internal.MIPlugin;
@@ -387,22 +387,22 @@ public class MIInferiorProcess extends Process
         }
     }
     
-    public void commandQueued(ICommand<? extends ICommandResult> command) {
+    public void commandQueued(ICommandToken token) {
         // No action 
     }
     
-    public void commandSent(ICommand<? extends ICommandResult> command) {
+    public void commandSent(ICommandToken token) {
-        if (command instanceof CLICommand<?>) {
+        if (token.getCommand() instanceof CLICommand<?>) {
             fSuppressTargetOutputCounter++;
         }
     }
     
-    public void commandRemoved(ICommand<? extends ICommandResult> command) {
+    public void commandRemoved(ICommandToken token) {
         // No action 
     }
     
-    public void commandDone(ICommand<? extends ICommandResult> command, ICommandResult result) {
+    public void commandDone(ICommandToken token, ICommandResult result) {
-    	if (command instanceof CLICommand<?>) {
+    	if (token.getCommand() instanceof CLICommand<?>) {
             fSuppressTargetOutputCounter--;
         }
 

plugins/org.eclipse.dd.mi/src/org/eclipse/dd/mi/service/command/MIRunControlEventProcessor.java

@@ -18,6 +18,7 @@ import org.eclipse.dd.dsf.debug.service.IRunControl.IContainerDMContext;
 import org.eclipse.dd.dsf.debug.service.command.ICommand;
 import org.eclipse.dd.dsf.debug.service.command.ICommandListener;
 import org.eclipse.dd.dsf.debug.service.command.ICommandResult;
+import org.eclipse.dd.dsf.debug.service.command.ICommandToken;
 import org.eclipse.dd.dsf.debug.service.command.IEventListener;
 import org.eclipse.dd.dsf.service.DsfServicesTracker;
 import org.eclipse.dd.mi.internal.MIPlugin;
@@ -177,19 +178,20 @@ public class MIRunControlEventProcessor
         return event;
     }
 
-    public void commandQueued(ICommand<?> command) {
+    public void commandQueued(ICommandToken token) {
         // Do nothing.
     }
     
-    public void commandSent(ICommand<?> command) {
+    public void commandSent(ICommandToken token) {
         // Do nothing.
     }
     
-    public void commandRemoved(ICommand<?> command) {
+    public void commandRemoved(ICommandToken token) {
         // Do nothing.
     }
     
-    public void commandDone(ICommand<?> cmd, ICommandResult result) {
+    public void commandDone(ICommandToken token, ICommandResult result) {
+        ICommand<?> cmd = token.getCommand();
     	MIInfo cmdResult = (MIInfo) result ;
     	MIOutput output =  cmdResult.getMIOutput();
     	MIResultRecord rr = output.getMIResultRecord();