Index: trunk/src/org/openstreetmap/josm/actions/OpenLocationAction.java
===================================================================
--- trunk/src/org/openstreetmap/josm/actions/OpenLocationAction.java	(revision 6031)
+++ trunk/src/org/openstreetmap/josm/actions/OpenLocationAction.java	(revision 6032)
@@ -20,11 +20,10 @@
 import javax.swing.JOptionPane;
 import javax.swing.JPanel;
-import javax.swing.SwingUtilities;
 
 import org.openstreetmap.josm.Main;
 import org.openstreetmap.josm.actions.downloadtasks.DownloadGpsTask;
 import org.openstreetmap.josm.actions.downloadtasks.DownloadOsmChangeCompressedTask;
+import org.openstreetmap.josm.actions.downloadtasks.DownloadOsmChangeTask;
 import org.openstreetmap.josm.actions.downloadtasks.DownloadOsmCompressedTask;
-import org.openstreetmap.josm.actions.downloadtasks.DownloadOsmChangeTask;
 import org.openstreetmap.josm.actions.downloadtasks.DownloadOsmTask;
 import org.openstreetmap.josm.actions.downloadtasks.DownloadOsmUrlTask;
@@ -32,6 +31,7 @@
 import org.openstreetmap.josm.actions.downloadtasks.PostDownloadHandler;
 import org.openstreetmap.josm.gui.ExtendedDialog;
+import org.openstreetmap.josm.gui.HelpAwareOptionPane;
+import org.openstreetmap.josm.gui.help.HelpUtil;
 import org.openstreetmap.josm.gui.progress.PleaseWaitProgressMonitor;
-import org.openstreetmap.josm.gui.util.GuiHelper;
 import org.openstreetmap.josm.gui.widgets.HistoryComboBox;
 import org.openstreetmap.josm.tools.Shortcut;
@@ -150,5 +150,6 @@
     /**
      * Summarizes acceptable urls for error message purposes.
-     * @since 6030
+     * @return The HTML message to be displayed
+     * @since 6031
      */
     public String findSummaryDocumentation() {
@@ -186,15 +187,15 @@
         } else {
             final String details = findSummaryDocumentation();    // Explain what patterns are supported
-            SwingUtilities.invokeLater(new Runnable() {
-                @Override
-                public void run() {
-                    JOptionPane.showMessageDialog(Main.parent, tr(
-                            "<html><p>Cannot open URL ''{0}''<br/>The following load tasks accept the URL patterns shown:<br/>{1}</p></html>",
-                            url, details), tr("Download Location"), JOptionPane.ERROR_MESSAGE);
-                }
-            });
+            HelpAwareOptionPane.showMessageDialogInEDT(Main.parent, tr(
+                    "<html><p>Cannot open URL ''{0}''<br/>The following download tasks accept the URL patterns shown:<br/>{1}</p></html>",
+                    url, details), tr("Download Location"), JOptionPane.ERROR_MESSAGE, HelpUtil.ht("/Action/OpenLocation"));
         }
     }
     
+    /**
+     * Adds a new download task to the supported ones.
+     * @param taskClass The new download task to add
+     * @return <tt>true</tt> (as specified by {@link Collection#add})
+     */
     public boolean addDownloadTaskClass(Class<? extends DownloadTask> taskClass) {
         return this.downloadTasks.add(taskClass);
Index: trunk/src/org/openstreetmap/josm/actions/downloadtasks/AbstractDownloadTask.java
===================================================================
--- trunk/src/org/openstreetmap/josm/actions/downloadtasks/AbstractDownloadTask.java	(revision 6031)
+++ trunk/src/org/openstreetmap/josm/actions/downloadtasks/AbstractDownloadTask.java	(revision 6032)
@@ -6,4 +6,8 @@
 import org.openstreetmap.josm.io.XmlWriter;
 
+/**
+ * Common abstract implementation of other download tasks
+ * @since 2322
+ */
 public abstract class AbstractDownloadTask implements DownloadTask {
     private List<Object> errorMessages;
Index: trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadOsmChangeCompressedTask.java
===================================================================
--- trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadOsmChangeCompressedTask.java	(revision 6031)
+++ trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadOsmChangeCompressedTask.java	(revision 6032)
@@ -12,4 +12,8 @@
 import org.openstreetmap.josm.io.OsmTransferException;
 
+/**
+ * Task allowing to download compressed OSM-Change files (gzip and bzip2)
+ * @since 5361
+ */
 public class DownloadOsmChangeCompressedTask extends DownloadOsmChangeTask {
 
Index: trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadOsmCompressedTask.java
===================================================================
--- trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadOsmCompressedTask.java	(revision 6031)
+++ trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadOsmCompressedTask.java	(revision 6032)
@@ -13,4 +13,8 @@
 import org.openstreetmap.josm.io.OsmTransferException;
 
+/**
+ * Task allowing to download compressed OSM files (gzip and bzip2)
+ * @since 5317
+ */
 public class DownloadOsmCompressedTask extends DownloadOsmTask {
 
Index: trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadOsmUrlTask.java
===================================================================
--- trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadOsmUrlTask.java	(revision 6031)
+++ trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadOsmUrlTask.java	(revision 6032)
@@ -9,4 +9,8 @@
 import org.openstreetmap.josm.tools.OsmUrlToBounds;
 
+/**
+ * Task allowing to download an OSM url containing coordinates
+ * @since 4996
+ */
 public class DownloadOsmUrlTask extends DownloadOsmTask {
 
Index: trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadTask.java
===================================================================
--- trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadTask.java	(revision 6031)
+++ trunk/src/org/openstreetmap/josm/actions/downloadtasks/DownloadTask.java	(revision 6032)
@@ -80,5 +80,7 @@
 
     /**
-     * Returns a short html documentation string, describing acceptable URLs.
+     * Returns a short HTML documentation string, describing acceptable URLs.
+     * @return The HTML documentation
+     * @since 6031
      */
     String acceptsDocumentationSummary();
@@ -86,9 +88,13 @@
     /**
      * Returns human-readable description of the task
+     * @return The task description
+     * @since 6031
      */
     String getTitle();
     
     /**
-     * Returns regular expression that match the URLs
+     * Returns regular expressions that match the URLs
+     * @return The array of accepted URL patterns
+     * @since 6031
      */
     String[] getPatterns();
