Merge remote-tracking branch 'origin/GP-2903_ghidra1_ImmutableDomainObjects--SQUASHED'

Ghidra/Features/Base/src/main/java/ghidra/app/util/task/OpenProgramTask.java

@@ -169,18 +169,7 @@ public class OpenProgramTask extends Task {
 		String path = url != null ? url.toString() : domainFile.getPathname();
 		Object obj = null;
 		try {
-
 			obj = domainFile.getReadOnlyDomainObject(consumer, version, taskMonitor);
-
-			if (obj == null) {
-				String errorMessage = "Can't open " + contentType + " - \"" + path + "\"";
-				if (version != DomainFile.DEFAULT_VERSION) {
-					errorMessage += " version " + version;
-				}
-
-				Msg.showError(this, null, "File Not Found", errorMessage);
-			}
-			
 		}
 		catch (CancelledException e) {
 			// we don't care, the task has been cancelled

Ghidra/Features/Base/src/main/java/ghidra/framework/main/OpenVersionedFileDialog.java

@@ -100,13 +100,17 @@ public class OpenVersionedFileDialog<T extends DomainObject> extends DataTreeDia
 	/**
 	 * Get the selected domain object for read-only or immutable use.
 	 * If an existing open object is selected its original mode applies but consumer will 
-	 * be added.
+	 * be added.  The caller/consumer is responsible for releasing the returned domain object
-	 * @param consumer consumer
+	 * when done using it (see {@link DomainObject#release(Object)}).
-	 * @param readOnly true if the domain object should be opened read only, versus immutable
+	 * @param consumer domain object consumer
-	 * @return null if a file was not selected
+	 * @param immutable true if the domain object should be opened immutable, else false for
+	 * read-only.  Immutable mode should not be used for content that will be modified.  If 
+	 * read-only indicated an upgrade will always be performed if required.
+	 * @return opened domain object or null if a file was not selected or if open failed to 
+	 * complete.
 	 */
 	@SuppressWarnings("unchecked") // relies on content class filter
-	public T getDomainObject(Object consumer, boolean readOnly) {
+	public T getDomainObject(Object consumer, boolean immutable) {
 		T dobj = null;
 		if (usingOpenProgramList()) {
 			dobj = getSelectedOpenDomainObject();
@@ -115,20 +119,19 @@ public class OpenVersionedFileDialog<T extends DomainObject> extends DataTreeDia
 			}
 			return dobj;
 		}
+		int version = DomainFile.DEFAULT_VERSION;
 		if (historyPanel != null) {
-			dobj = (T) historyPanel.getSelectedVersion(consumer, readOnly);
+			version = historyPanel.getSelectedVersionNumber();
 		}
-		if (dobj == null) {
+
-			DomainFile domainFile = getDomainFile();
+		DomainFile domainFile = getDomainFile();
-			if (domainFile != null) {
+		if (domainFile != null) {
-				GetVersionedObjectTask task =
+			GetDomainObjectTask task =
-					new GetVersionedObjectTask(consumer, domainFile, DomainFile.DEFAULT_VERSION,
+				new GetDomainObjectTask(consumer, domainFile, version, immutable);
-						readOnly);
+			tool.execute(task, 1000);
-				tool.execute(task, 1000);
+			return (T) task.getDomainObject();
-				return (T) task.getVersionedObject();
-			}
 		}
-		return dobj;
+		return null;
 	}
 
 	/**

Ghidra/Features/ProgramDiff/src/main/java/ghidra/app/plugin/core/diff/ProgramDiffPlugin.java

@@ -17,7 +17,6 @@ package ghidra.app.plugin.core.diff;
 
 import java.awt.*;
 import java.awt.event.*;
-import java.io.IOException;
 import java.lang.reflect.InvocationTargetException;
 import java.util.*;
 import java.util.List;
@@ -51,6 +50,7 @@ import ghidra.app.util.viewer.format.FormatManager;
 import ghidra.app.util.viewer.listingpanel.*;
 import ghidra.app.util.viewer.util.AddressIndexMap;
 import ghidra.app.util.viewer.util.FieldNavigator;
+import ghidra.framework.main.GetDomainObjectTask;
 import ghidra.framework.main.OpenVersionedFileDialog;
 import ghidra.framework.model.*;
 import ghidra.framework.options.*;
@@ -60,7 +60,8 @@ import ghidra.program.model.address.*;
 import ghidra.program.model.listing.*;
 import ghidra.program.util.*;
 import ghidra.util.*;
-import ghidra.util.exception.*;
+import ghidra.util.exception.AssertException;
+import ghidra.util.exception.CancelledException;
 import ghidra.util.task.*;
 import help.Help;
 import help.HelpService;
@@ -1143,7 +1144,7 @@ public class ProgramDiffPlugin extends ProgramPlugin
 			tool.clearStatusInfo();
 			JComponent component = dialog.getComponent();
 
-			Program dobj = dialog.getDomainObject(ProgramDiffPlugin.this, false);
+			Program dobj = dialog.getDomainObject(ProgramDiffPlugin.this, true);
 			if (dobj != null) {
 				if (openSecondProgram(dobj, component)) {
 					dialog.close();
@@ -1151,9 +1152,6 @@ public class ProgramDiffPlugin extends ProgramPlugin
 				}
 				return;
 			}
-
-			displayStatus(component, "Can't Open Selected Program",
-				"Please select a file, not a folder.", OptionDialog.INFORMATION_MESSAGE);
 		});
 		dialog.showComponent();
 	}
@@ -1531,16 +1529,19 @@ public class ProgramDiffPlugin extends ProgramPlugin
 	}
 
 	private boolean openSecondProgram(DomainFile df) {
+		if (!Program.class.isAssignableFrom(df.getDomainObjectClass())) {
+			Msg.error(this, "Failed to launch Diff for non-Program file: " + df.getName());
+			return false;
+		}
 
-		OpenSecondProgramTask task = new OpenSecondProgramTask(df);
+		GetDomainObjectTask task =
+			new GetDomainObjectTask(this, df, DomainFile.DEFAULT_VERSION, true);
 		new TaskLauncher(task, tool.getToolFrame(), 500);
 		// block until the task completes
 
-		if (!task.wasCanceled()) {
+		Program newProgram = (Program) task.getDomainObject();
-			Program newProgram = task.getDiffProgram();
+		if (newProgram != null) {
-			if (newProgram != null) {
+			return openSecondProgram(newProgram, null);
-				return openSecondProgram(newProgram, null);
-			}
 		}
 		return false;
 	}
@@ -1851,71 +1852,6 @@ public class ProgramDiffPlugin extends ProgramPlugin
 		}
 	}
 
-	private class OpenSecondProgramTask extends Task {
-		private DomainFile domainFile;
-		private Program diffProgram;
-		private TaskMonitor monitor;
-
-		OpenSecondProgramTask(DomainFile domainFile) {
-			super("Opening Program for Diff", true, true, true);
-			this.domainFile = domainFile;
-		}
-
-		@Override
-		public void run(TaskMonitor tm) {
-			this.monitor = tm;
-			try {
-				try {
-					monitor.setMessage("Waiting on program file...");
-					diffProgram =
-						(Program) domainFile.getImmutableDomainObject(ProgramDiffPlugin.this,
-							DomainFile.DEFAULT_VERSION, monitor);
-				}
-				catch (VersionException e) {
-					if (e.isUpgradable()) {
-						try {
-							diffProgram =
-								(Program) domainFile.getReadOnlyDomainObject(ProgramDiffPlugin.this,
-									DomainFile.DEFAULT_VERSION, monitor);
-						}
-						catch (VersionException exc) {
-							Msg.showError(this, null, "Error Getting Diff Program",
-								"Getting read only file failed");
-						}
-						catch (IOException exc) {
-							if (!monitor.isCancelled()) {
-								Msg.showError(this, null, "Error Getting Diff Program",
-									"Getting read only file failed", exc);
-							}
-						}
-					}
-					else {
-						Msg.showError(this, null, "Error Getting Diff Program",
-							"File cannot be upgraded.");
-
-					}
-				}
-				catch (IOException e) {
-					Msg.showError(this, null, "Error Getting Diff Program",
-						"Getting read only file failed", e);
-				}
-			}
-			catch (CancelledException e) {
-				// For now do nothing if user cancels
-			}
-
-			monitor.setMessage("");
-		}
-
-		boolean wasCanceled() {
-			return monitor.isCancelled();
-		}
-
-		Program getDiffProgram() {
-			return diffProgram;
-		}
-	}
-
 	@Override
 	public void domainObjectChanged(DomainObjectChangedEvent event) {
 		if (secondaryDiffProgram != null && diffDetailsProvider != null) {

Ghidra/Framework/Project/src/main/java/ghidra/framework/data/LinkHandler.java

@@ -20,7 +20,6 @@ import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.Map;
 
-import javax.help.UnsupportedOperationException;
 import javax.swing.Icon;
 
 import generic.theme.GIcon;
@@ -45,9 +44,6 @@ import ghidra.util.task.TaskMonitor;
  */
 public abstract class LinkHandler<T extends DomainObjectAdapterDB> extends DBContentHandler<T> {
 	
-	// TODO: Need to improve by making this meta data on file instead of database content.
-	//       Metadata use would eliminate need for DB but we lack support for non-DB files.
-
 	public static final String URL_METADATA_KEY = "link.url";
 
 	// 16x16 link icon where link is placed in lower-left corner
@@ -76,15 +72,29 @@ public abstract class LinkHandler<T extends DomainObjectAdapterDB> extends DBCon
 		}
 	}
 
-	@SuppressWarnings("unchecked")
 	@Override
 	public final T getReadOnlyObject(FolderItem item, int version, boolean okToUpgrade,
 			Object consumer, TaskMonitor monitor)
 			throws IOException, VersionException, CancelledException {
-
 		if (!okToUpgrade) {
-			throw new IllegalArgumentException("okToUpgrade must be true");
+			throw new UnsupportedOperationException("okToUpgrade must be true for link-file");
 		}
+		return getObject(item, version, consumer, monitor, false);
+	}
+
+	@Override
+	public T getImmutableObject(FolderItem item, Object consumer, int version, int minChangeVersion,
+			TaskMonitor monitor) throws IOException, CancelledException, VersionException {
+		if (minChangeVersion != -1) {
+			throw new UnsupportedOperationException("minChangeVersion must be -1 for link-file");
+		}
+		return getObject(item, version, consumer, monitor, true);
+	}
+
+	@SuppressWarnings("unchecked")
+	private T getObject(FolderItem item, int version, Object consumer, TaskMonitor monitor,
+			boolean immutable)
+			throws IOException, VersionException, CancelledException {
 
 		URL url = getURL(item);
 		
@@ -112,10 +122,11 @@ public abstract class LinkHandler<T extends DomainObjectAdapterDB> extends DBCon
 			DomainFile linkedFile = (DomainFile) content;
 			if (!getDomainObjectClass().isAssignableFrom(linkedFile.getDomainObjectClass())) {
 				throw new BadLinkException(
-					"Excepted " + getDomainObjectClass() + " but linked to " +
+					"Expected " + getDomainObjectClass() + " but linked to " +
 						linkedFile.getDomainObjectClass());
 			}
-			return (T) linkedFile.getReadOnlyDomainObject(consumer, version, monitor);
+			return immutable ? (T) linkedFile.getImmutableDomainObject(consumer, version, monitor)
+					: (T) linkedFile.getReadOnlyDomainObject(consumer, version, monitor);
 		}
 		finally {
 			if (content != null) {
@@ -128,16 +139,8 @@ public abstract class LinkHandler<T extends DomainObjectAdapterDB> extends DBCon
 	public final T getDomainObject(FolderItem item, FileSystem userfs, long checkoutId,
 			boolean okToUpgrade, boolean okToRecover, Object consumer, TaskMonitor monitor)
 			throws IOException, CancelledException, VersionException {
-		// Always upgrade if needed for read-only object
+		// getReadOnlyObject or getImmutableObject should be used
-		return getReadOnlyObject(item, DomainFile.DEFAULT_VERSION, true, consumer, monitor);
+		throw new UnsupportedOperationException("link-file does not support getDomainObject");
-	}
-
-	@Override
-	public T getImmutableObject(FolderItem item, Object consumer, int version, int minChangeVersion,
-			TaskMonitor monitor) throws IOException, CancelledException, VersionException {
-		//throw new UnsupportedOperationException("link-file does not support getImmutableObject");
-		// See GP-2903
-		return getReadOnlyObject(item, version, true, consumer, monitor);
 	}
 
 	@Override

Ghidra/Framework/Project/src/main/java/ghidra/framework/main/GetDomainObjectTask.java

@@ -0,0 +1,129 @@
+/* ###
+ * IP: GHIDRA
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package ghidra.framework.main;
+
+import java.io.IOException;
+
+import docking.widgets.OptionDialog;
+import ghidra.framework.client.ClientUtil;
+import ghidra.framework.model.DomainFile;
+import ghidra.framework.model.DomainObject;
+import ghidra.util.VersionExceptionHandler;
+import ghidra.util.exception.CancelledException;
+import ghidra.util.exception.VersionException;
+import ghidra.util.task.Task;
+import ghidra.util.task.TaskMonitor;
+
+/**
+ * A modal task that gets a domain object for a specified version.
+ * Object is either open read-only or immutable.  
+ * 
+ * NOTE: This task is not intended to open a domain file for modification and saving back 
+ * to a project.
+ * 
+ * A file open for read-only use will be upgraded if needed and is possible.  Once open it is 
+ * important that the specified consumer be released from the domain object when done using 
+ * the open object (see {@link DomainObject#release(Object)}).
+ */ 
+public class GetDomainObjectTask extends Task {
+
+	private Object consumer;
+	private DomainFile domainFile;
+	private int versionNumber;
+	private boolean immutable;
+
+	private DomainObject versionedObj;
+	
+	/**
+	 * Construct task open specified domainFile read only.  
+	 * An upgrade is performed if needed and is possible.
+	 * @param consumer consumer of the domain object
+	 * @param domainFile domain file
+	 * @param versionNumber version
+	 */
+	public GetDomainObjectTask(Object consumer, DomainFile domainFile, int versionNumber) {
+		this(consumer, domainFile, versionNumber, false);
+	}
+
+	/**
+	 * Construct task open specified domainFile read only or immutable.  Immutable mode should not
+	 * be used for content that will be modified.
+	 * If read-only an upgrade is performed if needed, if immutable the user will be prompted
+	 * if an upgrade should be performed if possible in which case it will open read-only.
+	 * @param consumer consumer of the domain object
+	 * @param domainFile domain file
+	 * @param versionNumber version
+	 * @param immutable true if the object should be open immutable, else read-only.
+	 */
+	public GetDomainObjectTask(Object consumer, DomainFile domainFile, int versionNumber,
+			boolean immutable) {
+		super("Get Versioned Domain Object", true, false, true);
+		this.consumer = consumer;
+		this.domainFile = domainFile;
+		this.versionNumber = versionNumber;
+		this.immutable = immutable;
+	}
+	
+	@Override
+    public void run(TaskMonitor monitor) {
+		String contentType = domainFile.getContentType();
+		try {
+			monitor.setMessage("Getting Version " + versionNumber + " for " + domainFile.getName());
+			if (immutable) {
+				versionedObj =
+					domainFile.getImmutableDomainObject(consumer, versionNumber, monitor);
+			}
+			else {
+				// Upgrade will be performed if required
+				versionedObj = domainFile.getReadOnlyDomainObject(consumer, versionNumber, monitor);
+			}
+		}
+		catch (CancelledException e) {
+			// ignore
+		}
+		catch (IOException e) {
+			ClientUtil.handleException(AppInfo.getActiveProject().getRepository(), e,
+				contentType + " Open", null);
+		} catch (VersionException e) {
+			if (immutable && e.isUpgradable()) {
+				String detailMessage =
+					e.getDetailMessage() == null ? "" : "\n" + e.getDetailMessage();
+				String title = "Upgrade " + contentType + " Data? " + domainFile.getName();
+				String message = "The " + contentType + " file you are attempting to open" +
+					" is an older version." + detailMessage + "\n \n" +
+					"Would you like to Upgrade it now?";
+				int rc = OptionDialog.showOptionDialog(null, title, message, "Upgrade",
+					OptionDialog.QUESTION_MESSAGE);
+				if (rc == OptionDialog.OPTION_ONE) {
+					// try again as read-only
+					immutable = false;
+					run(monitor);
+				}
+				return;
+			}
+			VersionExceptionHandler.showVersionError(null, domainFile.getName(),
+				domainFile.getContentType(), contentType + " Open", e);
+		}
+	}
+	
+	/**
+	 * Return the domain object instance.
+	 * @return domain object which was opened or null if task cancelled or failed
+	 */
+	public DomainObject getDomainObject() {
+		return versionedObj;
+	}
+}

Ghidra/Framework/Project/src/main/java/ghidra/framework/main/GetVersionedObjectTask.java

@@ -1,104 +0,0 @@
-/* ###
- * IP: GHIDRA
- * REVIEWED: YES
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- * 
- *      http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package ghidra.framework.main;
-
-import java.io.IOException;
-
-import ghidra.framework.client.ClientUtil;
-import ghidra.framework.model.DomainFile;
-import ghidra.framework.model.DomainObject;
-import ghidra.util.Msg;
-import ghidra.util.exception.CancelledException;
-import ghidra.util.exception.VersionException;
-import ghidra.util.task.Task;
-import ghidra.util.task.TaskMonitor;
-
-/**
- * A modal task that gets a domain object for a specific version.
- * 
- * 
- */ 
-public class GetVersionedObjectTask extends Task {
-
-	private Object consumer;
-	private DomainFile domainFile;
-	private int versionNumber;
-	private DomainObject versionedObj;
-	
-	/**
-	 * Constructor; task will get a read only domain object
-	 * @param consumer consumer of the domain object
-	 * @param domainFile domain file
-	 * @param versionNumber version
-	 */
-	public GetVersionedObjectTask(Object consumer,  DomainFile domainFile, 
-			int versionNumber) {
-		this(consumer, domainFile, versionNumber, true);
-	}
-	/**
-	 * Constructor
-	 * @param consumer consumer of the domain object
-	 * @param domainFile domain file
-	 * @param versionNumber version
-	 * @param readOnly true if the object should be read only versus
-	 * immutable
-	 */
-	public GetVersionedObjectTask(Object consumer,  DomainFile domainFile, 
-		int versionNumber, boolean readOnly) {
-		
-		super("Get Versioned Domain Object", true, false, true);
-		this.consumer = consumer;
-		this.domainFile = domainFile;
-		this.versionNumber = versionNumber;
-	}
-	
-	/* (non-Javadoc)
-	 * @see ghidra.util.task.Task#run(ghidra.util.task.TaskMonitor)
-	 */
-	@Override
-    public void run(TaskMonitor monitor) {
-		try {
-			monitor.setMessage("Getting Version " + versionNumber +
-				" for " + domainFile.getName());
-			versionedObj = 
-				domainFile.getReadOnlyDomainObject(consumer, versionNumber, 
-												   monitor); 
-		}catch (CancelledException e) {
-		}catch (IOException e) {
-			if (domainFile.isInWritableProject()) {
-				ClientUtil.handleException(AppInfo.getActiveProject().getRepository(), e, 
-						"Get Versioned Object", null);
-			}
-			else {
-				Msg.showError(this, null, 
-					"Error Getting Versioned Object", "Could not get version " + versionNumber + 
-					" for "  + domainFile.getName() + ": " + e, e);
-			}
-		} catch (VersionException e) {
-			Msg.showError(this, 
-				null,
-				"Error Getting Versioned Object", "Could not get version " + versionNumber + 
-				" for "  + domainFile.getName() + ": " + e); 
-		}
-	}
-	/**
-	 * Return the versioned domain object.
-	 */
-	public DomainObject getVersionedObject() {
-		return versionedObj;
-	}
-}

Ghidra/Framework/Project/src/main/java/ghidra/framework/main/ToolButton.java

@@ -370,9 +370,9 @@ class ToolButton extends EmptyBorderButton implements Draggable, Droppable {
 	}
 
 	private DomainObject getVersionedObject(DomainFile file, int versionNumber) {
-		GetVersionedObjectTask task = new GetVersionedObjectTask(this, file, versionNumber);
+		GetDomainObjectTask task = new GetDomainObjectTask(this, file, versionNumber);
 		plugin.getTool().execute(task, 250);
-		return task.getVersionedObject();
+		return task.getDomainObject();
 	}
 
 //==================================================================================================

Ghidra/Framework/Project/src/main/java/ghidra/framework/main/datatree/LocalVersionInfoHandler.java

@@ -22,7 +22,7 @@ import java.io.IOException;
 import docking.widgets.tree.GTreeNode;
 import ghidra.app.util.FileOpenDataFlavorHandler;
 import ghidra.framework.client.*;
-import ghidra.framework.main.GetVersionedObjectTask;
+import ghidra.framework.main.GetDomainObjectTask;
 import ghidra.framework.model.*;
 import ghidra.framework.plugintool.PluginTool;
 import ghidra.util.task.TaskLauncher;
@@ -35,15 +35,18 @@ public final class LocalVersionInfoHandler
 		VersionInfo info = (VersionInfo) obj;
 
 		DomainFile file = tool.getProject().getProjectData().getFile(info.getDomainFilePath());
-		GetVersionedObjectTask task =
+		GetDomainObjectTask task =
-			new GetVersionedObjectTask(this, file, info.getVersionNumber());
+			new GetDomainObjectTask(this, file, info.getVersionNumber());
 		tool.execute(task, 250);
-		DomainObject versionedObj = task.getVersionedObject();
+		DomainObject versionedObj = task.getDomainObject();
-
 		if (versionedObj != null) {
-			DomainFile vfile = versionedObj.getDomainFile();
+			try {
-			tool.acceptDomainFiles(new DomainFile[] { vfile });
+				DomainFile vfile = versionedObj.getDomainFile();
-			versionedObj.release(this);
+				tool.acceptDomainFiles(new DomainFile[] { vfile });
+			}
+			finally {
+				versionedObj.release(this);
+			}
 		}
 	}
 

Ghidra/Framework/Project/src/main/java/ghidra/framework/main/datatree/VersionHistoryPanel.java

@@ -38,7 +38,7 @@ import docking.widgets.OptionDialog;
 import docking.widgets.table.*;
 import ghidra.app.util.GenericHelpTopics;
 import ghidra.framework.client.ClientUtil;
-import ghidra.framework.main.GetVersionedObjectTask;
+import ghidra.framework.main.GetDomainObjectTask;
 import ghidra.framework.model.*;
 import ghidra.framework.plugintool.PluginTool;
 import ghidra.framework.store.ItemCheckoutStatus;
@@ -143,31 +143,36 @@ public class VersionHistoryPanel extends JPanel implements Draggable {
 	}
 
 	/**
-	 * Get the domain object for the selected version.
+	 * Get the selected {@link Version}.
-	 * @param consumer the consumer
+	 * @return selected {@link Version} or null if no selection
-	 * @param readOnly true if read only
-	 * @return null if there is no selection
 	 */
-	public DomainObject getSelectedVersion(Object consumer, boolean readOnly) {
+	public Version getSelectedVersion() {
 		int row = table.getSelectedRow();
 		if (row >= 0) {
-			Version version = tableModel.getVersionAt(row);
+			return tableModel.getVersionAt(row);
-			return getVersionedObject(consumer, version.getVersion(), readOnly);
 		}
 		return null;
 	}
 
+	/**
+	 * Determine if a version selection has been made.
+	 * @return true if version selection has been made, esle false
+	 */
 	public boolean isVersionSelected() {
 		return !table.getSelectionModel().isSelectionEmpty();
 	}
 
+	/**
+	 * Get the selected version number or {@link DomainFile#DEFAULT_VERSION} if no selection.
+	 * @return selected version number
+	 */
 	public int getSelectedVersionNumber() {
 		int row = table.getSelectedRow();
 		if (row >= 0) {
 			Version version = tableModel.getVersionAt(row);
 			return version.getVersion();
 		}
-		return -1;
+		return DomainFile.DEFAULT_VERSION;
 	}
 
 	@Override
@@ -260,11 +265,11 @@ public class VersionHistoryPanel extends JPanel implements Draggable {
 		dragSource.createDefaultDragGestureRecognizer(table, dragAction, dragGestureAdapter);
 	}
 
-	private DomainObject getVersionedObject(Object consumer, int versionNumber, boolean readOnly) {
+	private DomainObject getVersionedObject(Object consumer, int versionNumber, boolean immutable) {
-		GetVersionedObjectTask task =
+		GetDomainObjectTask task =
-			new GetVersionedObjectTask(consumer, domainFile, versionNumber, readOnly);
+			new GetDomainObjectTask(consumer, domainFile, versionNumber, immutable);
 		tool.execute(task, 1000);
-		return task.getVersionedObject();
+		return task.getDomainObject();
 	}
 
 	private void delete() {
@@ -337,13 +342,17 @@ public class VersionHistoryPanel extends JPanel implements Draggable {
 		Version version = tableModel.getVersionAt(row);
 		DomainObject versionedObj = getVersionedObject(this, version.getVersion(), true);
 		if (versionedObj != null) {
-			if (toolName != null) {
+			try {
-				tool.getToolServices().launchTool(toolName, versionedObj.getDomainFile());
+				if (toolName != null) {
+					tool.getToolServices().launchTool(toolName, versionedObj.getDomainFile());
+				}
+				else {
+					tool.getToolServices().launchDefaultTool(versionedObj.getDomainFile());
+				}
 			}
-			else {
+			finally {
-				tool.getToolServices().launchDefaultTool(versionedObj.getDomainFile());
+				versionedObj.release(this);
 			}
-			versionedObj.release(this);
 		}
 	}
 

Ghidra/Framework/Project/src/main/java/ghidra/framework/model/DomainFile.java

@@ -187,6 +187,9 @@ public interface DomainFile extends Comparable<DomainFile> {
 
 	/**
 	 * Returns a new DomainObject that cannot be changed or saved to its original file.
+	 * NOTE: The use of this method should generally be avoided since it can't
+	 * handle version changes that may have occured and require a data upgrade
+	 * (e.g., DB schema change).
 	 * @param consumer consumer of the domain object which is responsible for
 	 * releasing it after use.
 	 * @param version the domain object version requested.  DEFAULT_VERSION should be 

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/ProgramContentHandler.java

@@ -145,7 +145,6 @@ public class ProgramContentHandler extends DBWithUserDataContentHandler<ProgramD
 		}
 		catch (Throwable t) {
 			Msg.error(this, "getReadOnlyObject failed", t);
-			t.printStackTrace();
 			String msg = t.getMessage();
 			if (msg == null) {
 				msg = t.toString();