1 files changed, 78 insertions, 0 deletions
diff --git a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/command/SingleUseQueueingExtendedCommandExecutor.java b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/command/SingleUseQueueingExtendedCommandExecutor.java
new file mode 100644
index 0000000000..ab7b130b40
--- /dev/null
+++ b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/command/SingleUseQueueingExtendedCommandExecutor.java
@@ -0,0 +1,78 @@
+/*******************************************************************************
+ * Copyright (c) 2012 Oracle. 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:
+ *     Oracle - initial API and implementation
+ ******************************************************************************/
+package org.eclipse.jpt.common.utility.internal.command;
+
+import org.eclipse.jpt.common.utility.command.Command;
+import org.eclipse.jpt.common.utility.command.ExtendedCommandExecutor;
+import org.eclipse.jpt.common.utility.command.StatefulExtendedCommandExecutor;
+
+/**
+ * Calls to {@link #waitToExecute(Command)} will suspend the current thread
+ * until the command executor is {@link #start() started} and any previously-
+ * dispatched commands have executed.
+ * <p>
+ * <strong>NB:</strong> Calls to {@link #waitToExecute(Command)} will suspend
+ * the current thread <em>indefinitely</em> if the command executor is
+ * {@link #stop() stopped}.
+ * 
+ * @see AbstractSingleUseQueueingCommandExecutor
+ */
+public class SingleUseQueueingExtendedCommandExecutor
+	extends AbstractSingleUseQueueingCommandExecutor<StatefulExtendedCommandExecutor>
+	implements StatefulExtendedCommandExecutor
+{
+	public SingleUseQueueingExtendedCommandExecutor() {
+		this(ExtendedCommandExecutor.Default.instance());
+	}
+
+	public SingleUseQueueingExtendedCommandExecutor(ExtendedCommandExecutor commandExecutor) {
+		this(new SimpleStatefulExtendedCommandExecutor(commandExecutor));
+	}
+
+	public SingleUseQueueingExtendedCommandExecutor(StatefulExtendedCommandExecutor commandExecutor) {
+		super(commandExecutor);
+	}
+
+	public void waitToExecute(Command command) throws InterruptedException {
+		SynchronizingCommand syncCommand = new SynchronizingCommand();
+
+		this.execute(syncCommand);  // put the sync command on the queue and wait until it has executed
+
+		try {
+			syncCommand.waitForExecution();
+			this.commandExecutor.waitToExecute(command);
+		} finally {
+			syncCommand.release();
+		}
+	}
+
+	public boolean waitToExecute(Command command, long timeout) throws InterruptedException {
+		if (timeout == 0L) {
+			this.waitToExecute(command);
+			return true;
+		}
+
+		long stop = System.currentTimeMillis() + timeout;
+		SynchronizingCommand syncCommand = new SynchronizingCommand();
+
+		this.execute(syncCommand);  // dispatch the sync command to the other thread
+
+		try {
+			if (syncCommand.waitForExecution(timeout)) {
+				// adjust the time
+				timeout = stop - System.currentTimeMillis();
+				return (timeout > 0) && this.commandExecutor.waitToExecute(command, timeout);
+			}
+			return false;
+		} finally {
+			syncCommand.release();
+		}
+	}
+}