Disable viewer limit and mark new API as provisional

- made isExpandableNode() public to avoid force clients subclassing
Tree/Table viewers that shouldn't be extended.
- added EXPERIMENTAL to
-- isExpandableNode()  / setDisplayIncrementally()
-- IWorkbenchPreferenceConstants.LARGE_VIEW_LIMIT
-- WorkbenchViewerSetup
- adopted tests

Fixes #1030

Author: raghucssit

bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ColumnViewer.java

@@ -942,7 +942,7 @@ Object[] getChildrenWithLimitApplied(final Object parent, Item[] visibleChildren
 		} finally {
 			setDisplayIncrementally(limit);
 		}
-		
+
 		// model has lost some elements and length is less then visible items.
 		if (sortedAll.length < visibleItemsLength) {
 			return sortedAll;
@@ -993,6 +993,12 @@ int getItemsLimit() {
 	}
 
 	/**
+	 * <p>
+	 * <strong>EXPERIMENTAL</strong>. This class or interface has been added as part
+	 * of a work in progress. There is no guarantee that this API will work or that
+	 * it will remain the same. Please do not use this API without consulting with
+	 * the API development team.
+	 * </p>
 	 * Sets the viewers items limit on direct children at one level.
 	 * <p>
 	 * If the number of direct children will exceed this limit, the viewer will only
@@ -1045,11 +1051,18 @@ protected void handleDoubleSelect(SelectionEvent event) {
 	}
 
 	/**
-	 * @param element
+	 * <p>
+	 * <strong>EXPERIMENTAL</strong>. This class or interface has been added as part
+	 * of a work in progress. There is no guarantee that this API will work or that
+	 * it will remain the same. Please do not use this API without consulting with
+	 * the API development team.
+	 * </p>
+	 *
+	 * @param element model object representing a special "expandable" node
 	 * @return return if it is an instance of ExpandableNode
 	 * @since 3.31
 	 */
-	protected boolean isExpandableNode(Object element) {
+	public final boolean isExpandableNode(Object element) {
 		return element instanceof ExpandableNode;
 
 	}

bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/IWorkbenchPreferenceConstants.java

@@ -687,6 +687,13 @@ public interface IWorkbenchPreferenceConstants {
 	String DISPOSE_CLOSED_BROWSER_HOVER_TIMEOUT = "disposeClosedBrowserHoverTimeout"; //$NON-NLS-1$
 
 	/**
+	 * <p>
+	 * <strong>EXPERIMENTAL</strong>. This class or interface has been added as part
+	 * of a work in progress. There is no guarantee that this API will work or that
+	 * it will remain the same. Please do not use this API without consulting with
+	 * the API development team.
+	 * </p>
+	 *
 	 * This preference specifies the limit for number of children that can be shown
 	 * per parent element without expanding.
 	 * <p>

bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/WorkbenchPreferenceInitializer.java

@@ -126,8 +126,8 @@ public void initializeDefaultPreferences() {
 
 		node.putInt(IWorkbenchPreferenceConstants.DISPOSE_CLOSED_BROWSER_HOVER_TIMEOUT, -1);
 
-		// Don't show more than 10.000 child elements per parent by default
-		node.putInt(IWorkbenchPreferenceConstants.LARGE_VIEW_LIMIT, 1000);
+		// Disable viewer limit configuration until more testing and stabilization.
+		node.putInt(IWorkbenchPreferenceConstants.LARGE_VIEW_LIMIT, 0);
 
 		node.put(IWorkbenchPreferenceConstants.RESOURCE_RENAME_MODE,
 				IWorkbenchPreferenceConstants.RESOURCE_RENAME_MODE_INLINE);

bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/views/WorkbenchViewerSetup.java

@@ -26,6 +26,13 @@
 import org.eclipse.ui.internal.WorkbenchPlugin;
 
 /**
+ * <p>
+ * <strong>EXPERIMENTAL</strong>. This class or interface has been added as part
+ * of a work in progress. There is no guarantee that this API will work or that
+ * it will remain the same. Please do not use this API without consulting with
+ * the API development team.
+ * </p>
+ *
  * @since 3.130
  */
 public class WorkbenchViewerSetup {
@@ -58,8 +65,14 @@ public void propertyChange(PropertyChangeEvent event) {
 	}
 
 	/**
+	 * <p>
+	 * <strong>EXPERIMENTAL</strong>. This class or interface has been added as part
+	 * of a work in progress. There is no guarantee that this API will work or that
+	 * it will remain the same. Please do not use this API without consulting with
+	 * the API development team.
+	 * </p>
+	 *
 	 * Returns the current viewer limit set in the {@code General} preference page.
-	 * Default value is set to {@code 10000}
 	 *
 	 * @return {@link IWorkbenchPreferenceConstants#LARGE_VIEW_LIMIT}
 	 */
@@ -72,6 +85,13 @@ private static IPreferenceStore getPreferenceStore() {
 	}
 
 	/**
+	 * <p>
+	 * <strong>EXPERIMENTAL</strong>. This class or interface has been added as part
+	 * of a work in progress. There is no guarantee that this API will work or that
+	 * it will remain the same. Please do not use this API without consulting with
+	 * the API development team.
+	 * </p>
+	 *
 	 * Configure a {@link ColumnViewer} to show limited items per parent before
 	 * showing an ExpandableNode. Limit used is read from preference
 	 * {@link IWorkbenchPreferenceConstants#LARGE_VIEW_LIMIT}. Client must call this

tests/org.eclipse.jface.tests/src/org/eclipse/jface/tests/viewers/TableViewerWithLimitTest.java

@@ -329,11 +329,6 @@ class TestTableViewer extends TableViewer {
 		public TestTableViewer(Composite parent) {
 			super(parent);
 		}
-
-		@Override
-		public boolean isExpandableNode(Object element) {
-			return super.isExpandableNode(element);
-		}
 	}
 
 }

tests/org.eclipse.jface.tests/src/org/eclipse/jface/tests/viewers/TreeViewerWithLimitTest.java

@@ -327,11 +327,6 @@ class TestTreeViewer extends TreeViewer {
 		public TestTreeViewer(Composite parent) {
 			super(parent);
 		}
-
-		@Override
-		public boolean isExpandableNode(Object element) {
-			return super.isExpandableNode(element);
-		}
 	}
 
 }

tests/org.eclipse.ui.tests/Eclipse UI Tests/org/eclipse/ui/tests/preferences/ViewerItemsLimitTest.java

@@ -89,8 +89,9 @@ protected void doSetUp() throws Exception {
 		super.doSetUp();
 		cleanUp();
 		preferenceStore = WorkbenchPlugin.getDefault().getPreferenceStore();
-		int viewLimit = preferenceStore.getInt(IWorkbenchPreferenceConstants.LARGE_VIEW_LIMIT);
-		assertEquals("Default viewer limit must be " + DEFAULT_VIEW_LIMIT, DEFAULT_VIEW_LIMIT, viewLimit);
+		// TODO: preference is set to zero, enable once preference is restored
+//		int viewLimit = preferenceStore.getInt(IWorkbenchPreferenceConstants.LARGE_VIEW_LIMIT);
+//		assertEquals("Default viewer limit must be " + DEFAULT_VIEW_LIMIT, DEFAULT_VIEW_LIMIT, viewLimit);
 		window = getActiveWindow();
 		activePage = window.getActivePage();
 		defaultPerspective = activePage.getPerspective();