| /******************************************************************************* |
| * Copyright (c) 2005, 2007 IBM Corporation and others. |
| * 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: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.ui.internal.browser; |
| |
| import org.eclipse.core.runtime.CoreException; |
| import org.eclipse.core.runtime.IConfigurationElement; |
| import org.eclipse.core.runtime.IExtension; |
| import org.eclipse.core.runtime.IExtensionPoint; |
| import org.eclipse.core.runtime.Platform; |
| import org.eclipse.core.runtime.dynamichelpers.ExtensionTracker; |
| import org.eclipse.core.runtime.dynamichelpers.IExtensionChangeHandler; |
| import org.eclipse.core.runtime.dynamichelpers.IExtensionTracker; |
| import org.eclipse.swt.custom.BusyIndicator; |
| import org.eclipse.swt.widgets.Display; |
| import org.eclipse.ui.PartInitException; |
| import org.eclipse.ui.PlatformUI; |
| import org.eclipse.ui.browser.AbstractWorkbenchBrowserSupport; |
| import org.eclipse.ui.browser.IWebBrowser; |
| import org.eclipse.ui.browser.IWorkbenchBrowserSupport; |
| import org.eclipse.ui.internal.WorkbenchPlugin; |
| import org.eclipse.ui.internal.registry.IWorkbenchRegistryConstants; |
| |
| /** |
| * Implements the support interface and delegates the calls to the active |
| * support if contributed via the extension point, or the default support |
| * otherwise. |
| * |
| * @since 3.1 |
| */ |
| public class WorkbenchBrowserSupport extends AbstractWorkbenchBrowserSupport { |
| |
| private static WorkbenchBrowserSupport instance; |
| |
| private IWorkbenchBrowserSupport activeSupport; |
| |
| private boolean initialized; |
| |
| private String desiredBrowserSupportId; |
| |
| private IExtensionChangeHandler handler = new IExtensionChangeHandler() { |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.core.runtime.dynamicHelpers.IExtensionChangeHandler#addExtension(org.eclipse.core.runtime.dynamicHelpers.IExtensionTracker, org.eclipse.core.runtime.IExtension) |
| */ |
| public void addExtension(IExtensionTracker tracker,IExtension extension) { |
| //Do nothing |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.core.runtime.dynamicHelpers.IExtensionChangeHandler#removeExtension(org.eclipse.core.runtime.IExtension, java.lang.Object[]) |
| */ |
| public void removeExtension(IExtension source, Object[] objects) { |
| for (int i = 0; i < objects.length; i++) { |
| if (objects[i] == activeSupport) { |
| dispose(); |
| // remove ourselves - we'll be added again in initalize if |
| // needed |
| PlatformUI.getWorkbench().getExtensionTracker() |
| .unregisterHandler(handler); |
| } |
| } |
| } |
| }; |
| |
| /** |
| * Cannot be instantiated from outside. |
| */ |
| private WorkbenchBrowserSupport() { |
| } |
| |
| /** |
| * Returns the shared instance. |
| * |
| * @return shared instance |
| */ |
| public static IWorkbenchBrowserSupport getInstance() { |
| if (instance == null) { |
| instance = new WorkbenchBrowserSupport(); |
| } |
| return instance; |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.ui.browser.IWorkbenchBrowserSupport#createBrowser(int, java.lang.String, java.lang.String, java.lang.String) |
| */ |
| public IWebBrowser createBrowser(int style, String browserId, String name, |
| String tooltip) throws PartInitException { |
| return getActiveSupport() |
| .createBrowser(style, browserId, name, tooltip); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.ui.browser.IWorkbenchBrowserSupport#createBrowser(java.lang.String) |
| */ |
| public IWebBrowser createBrowser(String browserId) throws PartInitException { |
| return getActiveSupport().createBrowser(browserId); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.ui.browser.IWorkbenchBrowserSupport#isInternalWebBrowserAvailable() |
| */ |
| public boolean isInternalWebBrowserAvailable() { |
| return getActiveSupport().isInternalWebBrowserAvailable(); |
| } |
| |
| private IWorkbenchBrowserSupport getActiveSupport() { |
| if (initialized == false) { |
| loadActiveSupport(); |
| } |
| // ensure we always have an active instance |
| if (activeSupport == null) { |
| activeSupport = new DefaultWorkbenchBrowserSupport(); |
| } |
| return activeSupport; |
| } |
| |
| /** |
| * Answers whether the system has a non-default browser installed. |
| * |
| * @return whether the system has a non-default browser installed |
| */ |
| public boolean hasNonDefaultBrowser() { |
| return !(getActiveSupport() instanceof DefaultWorkbenchBrowserSupport); |
| } |
| |
| private void loadActiveSupport() { |
| BusyIndicator.showWhile(Display.getCurrent(), new Runnable() { |
| /* |
| * (non-Javadoc) |
| * |
| * @see java.lang.Runnable#run() |
| */ |
| public void run() { |
| IConfigurationElement[] elements = Platform |
| .getExtensionRegistry().getConfigurationElementsFor( |
| PlatformUI.PLUGIN_ID, |
| IWorkbenchRegistryConstants.PL_BROWSER_SUPPORT); |
| IConfigurationElement elementToUse = null; |
| |
| if (desiredBrowserSupportId != null) { |
| elementToUse = findDesiredElement(elements); |
| } else { |
| elementToUse = getElementToUse(elements); |
| } |
| if (elementToUse != null) { |
| initialized = initializePluggableBrowserSupport(elementToUse); |
| } |
| } |
| |
| /** |
| * Search for the element whose extension has ID equal to that of |
| * the field desiredBrowserSupport. |
| * |
| * @param elements |
| * the elements to search |
| * @return the element or <code>null</code> |
| */ |
| private IConfigurationElement findDesiredElement(IConfigurationElement [] elements) { |
| for (int i = 0; i < elements.length; i++) { |
| if (desiredBrowserSupportId.equals(elements[i].getDeclaringExtension().getUniqueIdentifier())) { |
| return elements[i]; |
| } |
| } |
| return null; |
| } |
| |
| private IExtensionPoint getExtensionPoint() { |
| return Platform.getExtensionRegistry() |
| .getExtensionPoint(PlatformUI.PLUGIN_ID, IWorkbenchRegistryConstants.PL_BROWSER_SUPPORT); |
| } |
| |
| private IConfigurationElement getElementToUse( |
| IConfigurationElement[] elements) { |
| if (elements.length == 0) { |
| return null; |
| } |
| IConfigurationElement defaultElement = null; |
| IConfigurationElement choice = null; |
| // find the first default element and |
| // the first non-default element. If non-default |
| // is found, pick it. Otherwise, use default. |
| for (int i = 0; i < elements.length; i++) { |
| IConfigurationElement element = elements[i]; |
| if (element.getName().equals(IWorkbenchRegistryConstants.TAG_SUPPORT)) { |
| String def = element.getAttribute(IWorkbenchRegistryConstants.ATT_DEFAULT); |
| if (def != null && Boolean.valueOf(def).booleanValue()) { |
| if (defaultElement == null) { |
| defaultElement = element; |
| } |
| } else { |
| // non-default |
| if (choice == null) { |
| choice = element; |
| } |
| } |
| } |
| } |
| if (choice == null) { |
| choice = defaultElement; |
| } |
| return choice; |
| } |
| |
| private boolean initializePluggableBrowserSupport( |
| IConfigurationElement element) { |
| // Instantiate the browser support |
| try { |
| activeSupport = (AbstractWorkbenchBrowserSupport) WorkbenchPlugin |
| .createExtension(element, IWorkbenchRegistryConstants.ATT_CLASS); |
| // start listening for removals |
| IExtensionTracker extensionTracker = PlatformUI.getWorkbench().getExtensionTracker(); |
| extensionTracker.registerHandler(handler, ExtensionTracker |
| .createExtensionPointFilter(getExtensionPoint())); |
| // register the new browser support for removal |
| // notification |
| extensionTracker |
| .registerObject(element.getDeclaringExtension(), |
| activeSupport, IExtensionTracker.REF_WEAK); |
| return true; |
| } catch (CoreException e) { |
| WorkbenchPlugin |
| .log("Unable to instantiate browser support" + e.getStatus(), e);//$NON-NLS-1$ |
| } |
| return false; |
| } |
| |
| }); |
| } |
| |
| /** |
| * For debug purposes only. |
| * |
| * @param desiredBrowserSupportId the desired browser system id |
| */ |
| public void setDesiredBrowserSupportId(String desiredBrowserSupportId) { |
| dispose(); // prep for a new help system |
| this.desiredBrowserSupportId = desiredBrowserSupportId; |
| } |
| |
| /** |
| * Dispose of the active support. |
| */ |
| protected void dispose() { |
| activeSupport = null; |
| initialized = false; |
| } |
| } |
