Streamlined use of Query object, in preparation for the memory view work (bug 160047).

plugins/org.eclipse.dd.dsf.debug.ui/src/org/eclipse/dd/dsf/debug/ui/sourcelookup/MISourceDisplayAdapter.java

@@ -274,7 +274,7 @@ public class MISourceDisplayAdapter implements ISourceDisplay
             // Query the service for frame data.  We are calling from a job thread, 
             // so we use the Query.get() method, which will block until the 
             // query is completed.
-            Query<FramePositioningData> query = new Query<FramePositioningData>(fExecutor) {
+            Query<FramePositioningData> query = new Query<FramePositioningData>() {
                 @Override
                 protected void execute(final DataRequestMonitor<FramePositioningData> rm) {
                     IStack stackService = fServicesTracker.getService(IStack.class); 

plugins/org.eclipse.dd.dsf.debug.ui/src/org/eclipse/dd/dsf/debug/ui/viewmodel/register/SyncRegisterDataAccess.java

@@ -17,7 +17,6 @@ import org.eclipse.core.runtime.IAdaptable;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.dd.dsf.concurrent.DataRequestMonitor;
-import org.eclipse.dd.dsf.concurrent.DsfExecutor;
 import org.eclipse.dd.dsf.concurrent.Query;
 import org.eclipse.dd.dsf.concurrent.ThreadSafeAndProhibitedFromDsfExecutor;
 import org.eclipse.dd.dsf.debug.service.IRegisters;
@@ -85,8 +84,8 @@ public class SyncRegisterDataAccess {
 
         private IBitFieldDMContext fDmc;
 
-        public GetBitFieldValueQuery(DsfExecutor executor, IBitFieldDMContext dmc) {
+        public GetBitFieldValueQuery(IBitFieldDMContext dmc) {
-            super(executor);
+            super();
             fDmc = dmc;
         }
 
@@ -159,7 +158,7 @@ public class SyncRegisterDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        GetBitFieldValueQuery query = new GetBitFieldValueQuery(session.getExecutor(), dmc);
+        GetBitFieldValueQuery query = new GetBitFieldValueQuery(dmc);
         session.getExecutor().execute(query);
 
         /*
@@ -183,8 +182,8 @@ public class SyncRegisterDataAccess {
         private String fValue;
         private String fFormatId;
 
-        public SetBitFieldValueQuery(DsfExecutor executor, IBitFieldDMContext dmc, String value, String formatId) {
+        public SetBitFieldValueQuery(IBitFieldDMContext dmc, String value, String formatId) {
-            super(executor);
+            super();
             fDmc = dmc;
             fValue = value;
             fFormatId = formatId;
@@ -262,7 +261,7 @@ public class SyncRegisterDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        SetBitFieldValueQuery query = new SetBitFieldValueQuery(session.getExecutor(), dmc, value, formatId);
+        SetBitFieldValueQuery query = new SetBitFieldValueQuery(dmc, value, formatId);
         session.getExecutor().execute(query);
 
         /*
@@ -292,8 +291,8 @@ public class SyncRegisterDataAccess {
 
         IMnemonic fMnemonic;
 
-        public SetBitFieldValueMnemonicQuery(DsfExecutor executor, IBitFieldDMContext dmc, IMnemonic mnemonic) {
+        public SetBitFieldValueMnemonicQuery(IBitFieldDMContext dmc, IMnemonic mnemonic) {
-            super(executor);
+            super();
             fDmc = dmc;
             fMnemonic = mnemonic;
         }
@@ -369,7 +368,7 @@ public class SyncRegisterDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        SetBitFieldValueMnemonicQuery query = new SetBitFieldValueMnemonicQuery( session.getExecutor(), dmc, mnemonic);
+        SetBitFieldValueMnemonicQuery query = new SetBitFieldValueMnemonicQuery(dmc, mnemonic);
         session.getExecutor().execute(query);
 
         /*
@@ -417,8 +416,8 @@ public class SyncRegisterDataAccess {
 
         IRegisterGroupDMContext fDmc;
 
-        public GetRegisterGroupValueQuery(DsfExecutor executor, IRegisterGroupDMContext dmc) {
+        public GetRegisterGroupValueQuery(IRegisterGroupDMContext dmc) {
-            super(executor);
+            super();
             fDmc = dmc;
         }
 
@@ -484,7 +483,7 @@ public class SyncRegisterDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        GetRegisterGroupValueQuery query = new GetRegisterGroupValueQuery(session.getExecutor(), dmc);
+        GetRegisterGroupValueQuery query = new GetRegisterGroupValueQuery(dmc);
         session.getExecutor().execute(query);
 
         /*
@@ -506,8 +505,8 @@ public class SyncRegisterDataAccess {
 
         IRegisterDMContext fDmc;
 
-        public GetRegisterValueQuery(DsfExecutor executor, IRegisterDMContext dmc) {
+        public GetRegisterValueQuery(IRegisterDMContext dmc) {
-            super(executor);
+            super();
             fDmc = dmc;
         }
 
@@ -573,7 +572,7 @@ public class SyncRegisterDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        GetRegisterValueQuery query = new GetRegisterValueQuery(session.getExecutor(), dmc);
+        GetRegisterValueQuery query = new GetRegisterValueQuery(dmc);
         session.getExecutor().execute(query);
 
         /*
@@ -597,8 +596,8 @@ public class SyncRegisterDataAccess {
         private String fValue;
         private String fFormatId;
 
-        public SetRegisterValueQuery(DsfExecutor executor, IRegisterDMContext dmc, String value, String formatId) {
+        public SetRegisterValueQuery(IRegisterDMContext dmc, String value, String formatId) {
-            super(executor);
+            super();
             fDmc = dmc;
             fValue = value;
             fFormatId = formatId;
@@ -681,7 +680,7 @@ public class SyncRegisterDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        SetRegisterValueQuery query = new SetRegisterValueQuery(session.getExecutor(), dmc, value, formatId);
+        SetRegisterValueQuery query = new SetRegisterValueQuery(dmc, value, formatId);
         session.getExecutor().execute(query);
 
         /*
@@ -708,8 +707,8 @@ public class SyncRegisterDataAccess {
 
         IFormattedDataDMContext<?> fDmc;
 
-        public GetSupportFormatsValueQuery(DsfExecutor executor, IFormattedDataDMContext<?> dmc) {
+        public GetSupportFormatsValueQuery(IFormattedDataDMContext<?> dmc) {
-            super(executor);
+            super();
             fDmc = dmc;
         }
 
@@ -783,7 +782,7 @@ public class SyncRegisterDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        GetSupportFormatsValueQuery query = new GetSupportFormatsValueQuery( session.getExecutor(), dmc);
+        GetSupportFormatsValueQuery query = new GetSupportFormatsValueQuery(dmc);
         session.getExecutor().execute(query);
 
         /*
@@ -806,8 +805,8 @@ public class SyncRegisterDataAccess {
         private IFormattedDataDMContext<?> fDmc;
         private String fFormatId;
 
-        public GetFormattedValueValueQuery(DsfExecutor executor, IFormattedDataDMContext<?> dmc, String formatId) {
+        public GetFormattedValueValueQuery(IFormattedDataDMContext<?> dmc, String formatId) {
-            super(executor);
+            super();
             fDmc = dmc;
             fFormatId = formatId;
         }
@@ -881,7 +880,7 @@ public class SyncRegisterDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        GetFormattedValueValueQuery query = new GetFormattedValueValueQuery(session.getExecutor(), dmc, formatId);
+        GetFormattedValueValueQuery query = new GetFormattedValueValueQuery(dmc, formatId);
         session.getExecutor().execute(query);
 
         /*

plugins/org.eclipse.dd.dsf.debug.ui/src/org/eclipse/dd/dsf/debug/ui/viewmodel/variable/SyncVariableDataAccess.java

@@ -12,7 +12,6 @@ import org.eclipse.core.runtime.IAdaptable;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.dd.dsf.concurrent.DataRequestMonitor;
-import org.eclipse.dd.dsf.concurrent.DsfExecutor;
 import org.eclipse.dd.dsf.concurrent.Query;
 import org.eclipse.dd.dsf.concurrent.ThreadSafeAndProhibitedFromDsfExecutor;
 import org.eclipse.dd.dsf.debug.service.IExpressions;
@@ -83,8 +82,8 @@ public class SyncVariableDataAccess {
 
         private IExpressionDMContext fDmc;
 
-        public GetVariableValueQuery(DsfExecutor executor, IExpressionDMContext dmc) {
+        public GetVariableValueQuery(IExpressionDMContext dmc) {
-            super(executor);
+            super();
             fDmc = dmc;
         }
 
@@ -157,7 +156,7 @@ public class SyncVariableDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        GetVariableValueQuery query = new GetVariableValueQuery(session.getExecutor(), dmc);
+        GetVariableValueQuery query = new GetVariableValueQuery(dmc);
         session.getExecutor().execute(query);
 
         /*
@@ -181,8 +180,8 @@ public class SyncVariableDataAccess {
         private String fValue;
         private String fFormatId;
 
-        public SetVariableValueQuery(DsfExecutor executor, IExpressionDMContext dmc, String value, String formatId) {
+        public SetVariableValueQuery(IExpressionDMContext dmc, String value, String formatId) {
-            super(executor);
+            super();
             fDmc = dmc;
             fValue = value;
             fFormatId = formatId;
@@ -260,7 +259,7 @@ public class SyncVariableDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        SetVariableValueQuery query = new SetVariableValueQuery(session.getExecutor(), dmc, value, formatId);
+        SetVariableValueQuery query = new SetVariableValueQuery(dmc, value, formatId);
         session.getExecutor().execute(query);
 
         /*
@@ -294,8 +293,8 @@ public class SyncVariableDataAccess {
 
         IFormattedDataDMContext<?> fDmc;
 
-        public GetSupportFormatsValueQuery(DsfExecutor executor, IFormattedDataDMContext<?> dmc) {
+        public GetSupportFormatsValueQuery(IFormattedDataDMContext<?> dmc) {
-            super(executor);
+            super();
             fDmc = dmc;
         }
 
@@ -369,7 +368,7 @@ public class SyncVariableDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        GetSupportFormatsValueQuery query = new GetSupportFormatsValueQuery(session.getExecutor(), dmc);
+        GetSupportFormatsValueQuery query = new GetSupportFormatsValueQuery(dmc);
         session.getExecutor().execute(query);
 
         /*
@@ -392,8 +391,8 @@ public class SyncVariableDataAccess {
         private IFormattedDataDMContext<?> fDmc;
         private String fFormatId;
 
-        public GetFormattedValueValueQuery(DsfExecutor executor, IFormattedDataDMContext<?> dmc, String formatId) {
+        public GetFormattedValueValueQuery(IFormattedDataDMContext<?> dmc, String formatId) {
-            super(executor);
+            super();
             fDmc = dmc;
             fFormatId = formatId;
         }
@@ -467,7 +466,7 @@ public class SyncVariableDataAccess {
          * guard agains RejectedExecutionException, because
          * DsfSession.getSession() above would only return an active session.
          */
-        GetFormattedValueValueQuery query = new GetFormattedValueValueQuery(session.getExecutor(), dmc, formatId);
+        GetFormattedValueValueQuery query = new GetFormattedValueValueQuery(dmc, formatId);
         session.getExecutor().execute(query);
 
         /*

plugins/org.eclipse.dd.dsf.debug/src/org/eclipse/dd/dsf/debug/sourcelookup/DsfMISourceLookupParticipant.java

@@ -183,7 +183,7 @@ public class DsfMISourceLookupParticipant implements ISourceLookupParticipant {
         }
         
         final IDMContext<?> dmc = (IDMContext<?>)object;
-        Query<String> query = new Query<String>(fExecutor) { 
+        Query<String> query = new Query<String>() { 
             @Override
             protected void execute(final DataRequestMonitor<String> rm) {
                 getSourceNameOnDispatchThread(dmc, rm);

plugins/org.eclipse.dd.dsf/src/org/eclipse/dd/dsf/concurrent/CountingRequestMonitor.java

@@ -10,6 +10,8 @@
  *******************************************************************************/
 package org.eclipse.dd.dsf.concurrent;
 
+import java.util.concurrent.Executor;
+
 import org.eclipse.core.runtime.MultiStatus;
 import org.eclipse.dd.dsf.DsfPlugin;
 
@@ -37,7 +39,7 @@ import org.eclipse.dd.dsf.DsfPlugin;
 public class CountingRequestMonitor extends RequestMonitor {
     private int fDoneCounter;
 
-    public CountingRequestMonitor(DsfExecutor executor, RequestMonitor parentRequestMonitor) {
+    public CountingRequestMonitor(Executor executor, RequestMonitor parentRequestMonitor) {
         super(executor, parentRequestMonitor);
         setStatus(new MultiStatus(DsfPlugin.PLUGIN_ID, 0, "Collective status for set of sub-operations.", null)); //$NON-NLS-1$
     }

plugins/org.eclipse.dd.dsf/src/org/eclipse/dd/dsf/concurrent/DataRequestMonitor.java

@@ -10,6 +10,8 @@
  *******************************************************************************/
 package org.eclipse.dd.dsf.concurrent;
 
+import java.util.concurrent.Executor;
+
 
 /**
  * Request monitor that allows data to be returned to the request initiator.
@@ -21,7 +23,7 @@ public class DataRequestMonitor<V> extends RequestMonitor {
     /** Data object reference */
     private V fData; 
     
-    public DataRequestMonitor(DsfExecutor executor, RequestMonitor parentRequestMonitor) {
+    public DataRequestMonitor(Executor executor, RequestMonitor parentRequestMonitor) {
         super(executor, parentRequestMonitor);
     }
 

plugins/org.eclipse.dd.dsf/src/org/eclipse/dd/dsf/concurrent/DefaultDsfExecutor.java

@@ -88,7 +88,7 @@ public class DefaultDsfExecutor extends ScheduledThreadPoolExecutor
     static {
         DEBUG_EXECUTOR = DsfPlugin.DEBUG && "true".equals( //$NON-NLS-1$
             Platform.getDebugOption("org.eclipse.dd.dsf/debug/executor")); //$NON-NLS-1$
-        assert ASSERTIONS_ENABLED = true;
+        assert (ASSERTIONS_ENABLED = true) == true;
     }  
 
     /** 

plugins/org.eclipse.dd.dsf/src/org/eclipse/dd/dsf/concurrent/DsfExecutable.java

@@ -40,7 +40,7 @@ public class DsfExecutable {
     static boolean ASSERTIONS_ENABLED = false;
 
     static {
-        assert ASSERTIONS_ENABLED = true;
+        assert (ASSERTIONS_ENABLED = true) == true;
         DEBUG_EXECUTOR = DsfPlugin.DEBUG && "true".equals( //$NON-NLS-1$
                 Platform.getDebugOption("org.eclipse.dd.dsf/debug/executor")); //$NON-NLS-1$
     }  

plugins/org.eclipse.dd.dsf/src/org/eclipse/dd/dsf/concurrent/MultiRequestMonitor.java

@@ -14,6 +14,7 @@ import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.Executor;
 
 import org.eclipse.core.runtime.MultiStatus;
 import org.eclipse.dd.dsf.DsfPlugin;
@@ -44,7 +45,7 @@ public class MultiRequestMonitor<V extends RequestMonitor> extends RequestMonito
     private Map<V,Boolean> fStatusMap = new HashMap<V,Boolean>();
     private int fDoneCounter;
 
-    public MultiRequestMonitor(DsfExecutor executor, RequestMonitor parentRequestMonitor) {
+    public MultiRequestMonitor(Executor executor, RequestMonitor parentRequestMonitor) {
         super(executor, parentRequestMonitor);
         setStatus(new MultiStatus(DsfPlugin.PLUGIN_ID, 0, "Collective status for set of sub-operations.", null)); //$NON-NLS-1$
     }

plugins/org.eclipse.dd.dsf/src/org/eclipse/dd/dsf/concurrent/Query.java

@@ -12,6 +12,7 @@ package org.eclipse.dd.dsf.concurrent;
 
 import java.util.concurrent.CancellationException;
 import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executor;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
@@ -26,7 +27,26 @@ import org.eclipse.core.runtime.CoreException;
  * a Callable<V> in that it allows the implementation code to calculate
  * the result in several dispatches, rather than requiring it to return the 
  * data at end of Callable#call method.
+ * <p>
+ * Usage:<br/>
+ * <pre>
+ *     class DataQuery extends Query<Data> {
+ *         protected void execute(DataRequestMonitor<Data> rm) {
+ *             rm.setData(fSlowService.getData());
+ *             rm.done();
+ *         }
+ *     }
  *     
+ *     DsfExecutor executor = getExecutor();
+ *     DataQuery query = new DataQuery();
+ *     executor.submit(query);
+ *     
+ *     try {
+ *         Data data = query.get();
+ *     }
+ *     
+ * </pre>
+ * <p> 
  * @see java.util.concurrent.Callable
  */
 @ThreadSafe
@@ -36,13 +56,22 @@ abstract public class Query<V> extends DsfRunnable
     /** The synchronization object for this query */
     private final Sync fSync = new Sync();
 
-    /** The executor that is used to complete the asynchronous operation of this query */ 
+    /**
-    private final DsfExecutor fExecutor;
+     * The Query constructor no longer requires an executor to be specified.
-    
+     * This executor was used to contruct the DataRequestMonitor argument to the
+     * {@link #execute(DataRequestMonitor)} method.  But a simplification in the 
+     * RequestMonitor object, made this unnecessary.
+     * @param executor
+     */
+    @Deprecated
     public Query(DsfExecutor executor) {
-        fExecutor = executor;
     }
     
+    /** 
+     * The no-argument constructor 
+     */
+    public Query() {}
+    
     public V get() throws InterruptedException, ExecutionException { return fSync.doGet(); }
 
     public V get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException {
@@ -71,7 +100,25 @@ abstract public class Query<V> extends DsfRunnable
     public void run() {
         if (fSync.doRun()) {
             try {
-                execute(new DataRequestMonitor<V>(fExecutor, null) {
+                /*
+                 * Create the executor which is going to handle the completion of the
+                 * request monitor.  Normally a DSF executor is supplied here which
+                 * causes the request monitor to be invoked in a new dispatch loop.
+                 * But since the query is a synchronization object, it can handle
+                 * the completion of the request in any thread.  
+                 * Avoiding the use of a DSF executor is very useful because queries are
+                 * meant to be used by clients calling from non-dispatch thread, and there
+                 * is a chance that a client may execute a query just as a session is being
+                 * shut down.  In that case, the DSF executor may throw a 
+                 * RejectedExecutionException which would have to be handled by the query.
+                 */
+                Executor rmExecutor = new Executor() {
+                    public void execute(Runnable command) {
+                        command.run();
+                    }
+                };
+                
+                execute(new DataRequestMonitor<V>(rmExecutor, null) {
                     @Override
                     public void handleCompleted() {
                         if (getStatus().isOK()) fSync.doSet(getData());

plugins/org.eclipse.dd.dsf/src/org/eclipse/dd/dsf/concurrent/RequestMonitor.java

@@ -10,6 +10,9 @@
  *******************************************************************************/
 package org.eclipse.dd.dsf.concurrent;
 
+import java.util.concurrent.Executor;
+import java.util.concurrent.RejectedExecutionException;
+
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.MultiStatus;
 import org.eclipse.core.runtime.Status;
@@ -59,7 +62,7 @@ public class RequestMonitor {
      * The executor that will be used in order to invoke the handler of the results
      * of the request.
      */
-    private final DsfExecutor fExecutor;
+    private final Executor fExecutor;
     
     /**
      * The request monitor which was used to call into the method that created this 
@@ -81,7 +84,7 @@ public class RequestMonitor {
      * @param parentRequestMonitor The optional parent request monitor to be invoked by
      * default when this request completes.  Parameter may be null.
      */
-    public RequestMonitor(DsfExecutor executor, RequestMonitor parentRequestMonitor) {
+    public RequestMonitor(Executor executor, RequestMonitor parentRequestMonitor) {
         fExecutor = executor;
         fParentRequestMonitor = parentRequestMonitor;
     }
@@ -139,6 +142,7 @@ public class RequestMonitor {
             throw new IllegalStateException("RequestMonitor: " + this + ", done() method called more than once");  //$NON-NLS-1$//$NON-NLS-2$
         }
         fDone = true;
+        try {
             fExecutor.execute(new DsfRunnable() {
                 public void run() {
                     RequestMonitor.this.handleCompleted();
@@ -148,6 +152,9 @@ public class RequestMonitor {
                     return "Completed: " + RequestMonitor.this.toString(); //$NON-NLS-1$
                 }
             });
+        } catch (RejectedExecutionException e) {
+            handleRejectedExecutionException();
+        }
     }
     
     /**
@@ -231,7 +238,7 @@ public class RequestMonitor {
             fParentRequestMonitor.setMultiStatus(DsfPlugin.PLUGIN_ID, getStatus().getCode(), "Failed: " + toString(), getStatus()); //$NON-NLS-1$
             fParentRequestMonitor.done();
         } else {
-            MultiStatus logStatus = new MultiStatus(DsfPlugin.PLUGIN_ID, IDsfService.INTERNAL_ERROR, "Request for monitor: '" + this + "' resulted in an error.", null); //$NON-NLS-1$ //$NON-NLS-2$
+            MultiStatus logStatus = new MultiStatus(DsfPlugin.PLUGIN_ID, IDsfService.INTERNAL_ERROR, "Request for monitor: '" + toString() + "' resulted in an error.", null); //$NON-NLS-1$ //$NON-NLS-2$
             logStatus.merge(getStatus());
             DsfPlugin.getDefault().getLog().log(logStatus);
         }
@@ -250,4 +257,20 @@ public class RequestMonitor {
             fParentRequestMonitor.done();
         }
     }
+    
+    /**
+     * Default handler for when the executor supplied in the constructor 
+     * rejects the runnable that is submitted invoke this requrest monitor.
+     * This usually happens only when the executor is shutting down.
+     */
+    protected void handleRejectedExecutionException() {
+        if (fParentRequestMonitor != null) {
+            fParentRequestMonitor.setMultiStatus(DsfPlugin.PLUGIN_ID, IDsfService.INVALID_STATE, "Rejected execution exception when trying to complete the request monitor: " + toString(), getStatus()); //$NON-NLS-1$
+            fParentRequestMonitor.done();
+        } else {
+            MultiStatus logStatus = new MultiStatus(DsfPlugin.PLUGIN_ID, IDsfService.INTERNAL_ERROR, "Request for monitor: '" + toString() + "' resulted in a rejected execution exception.", null); //$NON-NLS-1$ //$NON-NLS-2$
+            logStatus.merge(getStatus());
+            DsfPlugin.getDefault().getLog().log(logStatus);
+        }
+    }
 }