### Eclipse Workspace Patch 1.0
#P org.eclipse.debug.ui
Index: ui/org/eclipse/debug/internal/ui/launchConfigurations/LaunchHistory.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.debug.ui/ui/org/eclipse/debug/internal/ui/launchConfigurations/LaunchHistory.java,v
retrieving revision 1.37
diff -u -r1.37 LaunchHistory.java
--- ui/org/eclipse/debug/internal/ui/launchConfigurations/LaunchHistory.java	11 May 2007 18:56:49 -0000	1.37
+++ ui/org/eclipse/debug/internal/ui/launchConfigurations/LaunchHistory.java	9 Jul 2007 18:10:53 -0000
@@ -50,6 +50,12 @@
 	private Vector fFavorites = new Vector();
 	
 	/**
+	 * A new saved flag to prevent save participants from serializing unchanged launch histories.
+	 * @since 3.3.1
+	 */
+	private boolean fSaved = true;
+	
+	/**
 	 * List of instances of this launch history 
 	 */
 	private static List fgLaunchHistoryInstances = new ArrayList();
@@ -87,7 +93,7 @@
 	
 	/**
 	 * Returns if the current history contains the specified <code>ILaunchConfiguration</code>
-	 * @param config the config to look for
+	 * @param config the configuration to look for
 	 * @return true if the current history contains the specified configuration, false otherwise
 	 * @since 3.3
 	 */
@@ -135,6 +141,27 @@
 	 */
 	private void fireLaunchHistoryChanged() {
 		DebugUIPlugin.getDefault().getLaunchConfigurationManager().fireLaunchHistoryChanged();
+		setSaved(false);
+	}
+	
+	/**
+	 * Returns if the launch history requires saving or not
+	 * @return true if the history needs to be saved, false otherwise
+	 * @since 3.3.1
+	 */
+	public boolean needsSaving() {
+		return !fSaved;
+	}
+	
+	/**
+	 * Allows the dirty flag for this launch history to be set.
+	 * It is the clients of this class that must set the saved flag to true
+	 * if they have persisted the launch history
+	 * @param saved
+	 * @since 3.3.1
+	 */
+	public void setSaved(boolean saved) {
+		fSaved = saved;
 	}
 	
 	/**
@@ -230,6 +257,7 @@
 	 */
 	public synchronized void setFavorites(ILaunchConfiguration[] favorites) {
 		fFavorites = new Vector(Arrays.asList(favorites));
+		setSaved(false);
 	}	
 	
 	/**
@@ -240,6 +268,7 @@
 	public synchronized void addFavorite(ILaunchConfiguration configuration) {
 		if (!fFavorites.contains(configuration)) {
 			fFavorites.add(configuration);
+			setSaved(false);
 		}
 	}
 	
@@ -365,6 +394,7 @@
 	 */
 	protected synchronized void removeFavorite(ILaunchConfiguration configuration) {
 		fFavorites.remove(configuration);
+		setSaved(false);
 	}
 
 	/**
Index: ui/org/eclipse/debug/internal/ui/launchConfigurations/LaunchConfigurationManager.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.debug.ui/ui/org/eclipse/debug/internal/ui/launchConfigurations/LaunchConfigurationManager.java,v
retrieving revision 1.99
diff -u -r1.99 LaunchConfigurationManager.java
--- ui/org/eclipse/debug/internal/ui/launchConfigurations/LaunchConfigurationManager.java	31 May 2007 01:53:49 -0000	1.99
+++ ui/org/eclipse/debug/internal/ui/launchConfigurations/LaunchConfigurationManager.java	9 Jul 2007 18:10:53 -0000
@@ -390,8 +390,8 @@
 			Element favs = doc.createElement(IConfigurationElementConstants.FAVORITES);
 			groupElement.appendChild(favs);
 			createEntry(doc, favs, history.getFavorites());
+			history.setSaved(true);
 		}
-		
 		return DebugUIPlugin.serializeDocument(doc);
 	}
 
@@ -432,15 +432,21 @@
 				return;
 			}			
 		}
-		IPath historyPath = getHistoryFilePath();
-		String osHistoryPath = historyPath.toOSString();
-		String xml = getHistoryAsXML();
-		File file = new File(osHistoryPath);
-		file.createNewFile();
-		
-		FileOutputStream stream = new FileOutputStream(file);
-		stream.write(xml.getBytes("UTF8")); //$NON-NLS-1$
-		stream.close();
+		boolean shouldsave = false;
+		for(Iterator iter = fLaunchHistories.values().iterator(); iter.hasNext();) {
+			shouldsave |= ((LaunchHistory)iter.next()).needsSaving();
+		}
+		if(shouldsave) {
+			IPath historyPath = getHistoryFilePath();
+			String osHistoryPath = historyPath.toOSString();
+			String xml = getHistoryAsXML();
+			File file = new File(osHistoryPath);
+			file.createNewFile();
+			
+			FileOutputStream stream = new FileOutputStream(file);
+			stream.write(xml.getBytes("UTF8")); //$NON-NLS-1$
+			stream.close();
+		}
 	}
 	
 	/**