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1
11 package org.eclipse.ui.internal.browser;
12
13 import org.eclipse.core.runtime.CoreException;
14 import org.eclipse.core.runtime.IConfigurationElement;
15 import org.eclipse.core.runtime.IExtension;
16 import org.eclipse.core.runtime.IExtensionPoint;
17 import org.eclipse.core.runtime.Platform;
18 import org.eclipse.core.runtime.dynamichelpers.ExtensionTracker;
19 import org.eclipse.core.runtime.dynamichelpers.IExtensionChangeHandler;
20 import org.eclipse.core.runtime.dynamichelpers.IExtensionTracker;
21 import org.eclipse.swt.custom.BusyIndicator;
22 import org.eclipse.swt.widgets.Display;
23 import org.eclipse.ui.PartInitException;
24 import org.eclipse.ui.PlatformUI;
25 import org.eclipse.ui.browser.AbstractWorkbenchBrowserSupport;
26 import org.eclipse.ui.browser.IWebBrowser;
27 import org.eclipse.ui.browser.IWorkbenchBrowserSupport;
28 import org.eclipse.ui.internal.WorkbenchPlugin;
29 import org.eclipse.ui.internal.registry.IWorkbenchRegistryConstants;
30
31
38 public class WorkbenchBrowserSupport extends AbstractWorkbenchBrowserSupport {
39
40 private static WorkbenchBrowserSupport instance;
41
42 private IWorkbenchBrowserSupport activeSupport;
43
44 private boolean initialized;
45
46 private String  desiredBrowserSupportId;
47
48 private IExtensionChangeHandler handler = new IExtensionChangeHandler() {
49
50
53 public void addExtension(IExtensionTracker tracker,IExtension extension) {
54 }
56
57
60 public void removeExtension(IExtension source, Object [] objects) {
61 for (int i = 0; i < objects.length; i++) {
62 if (objects[i] == activeSupport) {
63 dispose();
64 PlatformUI.getWorkbench().getExtensionTracker()
67 .unregisterHandler(handler);
68 }
69 }
70 }
71 };
72
73
76 private WorkbenchBrowserSupport() {
77 }
78
79
84 public static IWorkbenchBrowserSupport getInstance() {
85 if (instance == null) {
86 instance = new WorkbenchBrowserSupport();
87 }
88 return instance;
89 }
90
91
94 public IWebBrowser createBrowser(int style, String browserId, String name,
95 String tooltip) throws PartInitException {
96 return getActiveSupport()
97 .createBrowser(style, browserId, name, tooltip);
98 }
99
100
103 public IWebBrowser createBrowser(String browserId) throws PartInitException {
104 return getActiveSupport().createBrowser(browserId);
105 }
106
107
110 public boolean isInternalWebBrowserAvailable() {
111 return getActiveSupport().isInternalWebBrowserAvailable();
112 }
113
114 private IWorkbenchBrowserSupport getActiveSupport() {
115 if (initialized == false) {
116 loadActiveSupport();
117 }
118 if (activeSupport == null) {
120 activeSupport = new DefaultWorkbenchBrowserSupport();
121 }
122 return activeSupport;
123 }
124
125
130 public boolean hasNonDefaultBrowser() {
131 return !(getActiveSupport() instanceof DefaultWorkbenchBrowserSupport);
132 }
133
134 private void loadActiveSupport() {
135 BusyIndicator.showWhile(Display.getCurrent(), new Runnable () {
136
141 public void run() {
142 IConfigurationElement[] elements = Platform
143 .getExtensionRegistry().getConfigurationElementsFor(
144 PlatformUI.PLUGIN_ID,
145 IWorkbenchRegistryConstants.PL_BROWSER_SUPPORT);
146 IConfigurationElement elementToUse = null;
147
148 if (desiredBrowserSupportId != null) {
149 elementToUse = findDesiredElement(elements);
150 } else {
151 elementToUse = getElementToUse(elements);
152 }
153 if (elementToUse != null) {
154 initialized = initializePluggableBrowserSupport(elementToUse);
155 }
156 }
157
158
166 private IConfigurationElement findDesiredElement(IConfigurationElement [] elements) {
167 for (int i = 0; i < elements.length; i++) {
168 if (desiredBrowserSupportId.equals(elements[i].getDeclaringExtension().getUniqueIdentifier())) {
169 return elements[i];
170 }
171 }
172 return null;
173 }
174
175 private IExtensionPoint getExtensionPoint() {
176 return Platform.getExtensionRegistry()
177 .getExtensionPoint(PlatformUI.PLUGIN_ID, IWorkbenchRegistryConstants.PL_BROWSER_SUPPORT);
178 }
179
180 private IConfigurationElement getElementToUse(
181 IConfigurationElement[] elements) {
182 if (elements.length == 0) {
183 return null;
184 }
185 IConfigurationElement defaultElement = null;
186 IConfigurationElement choice = null;
187 for (int i = 0; i < elements.length; i++) {
191 IConfigurationElement element = elements[i];
192 if (element.getName().equals(IWorkbenchRegistryConstants.TAG_SUPPORT)) {
193 String def = element.getAttribute(IWorkbenchRegistryConstants.ATT_DEFAULT);
194 if (def != null && Boolean.valueOf(def).booleanValue()) {
195 if (defaultElement == null) {
196 defaultElement = element;
197 }
198 } else {
199 if (choice == null) {
201 choice = element;
202 }
203 }
204 }
205 }
206 if (choice == null) {
207 choice = defaultElement;
208 }
209 return choice;
210 }
211
212 private boolean initializePluggableBrowserSupport(
213 IConfigurationElement element) {
214 try {
216 activeSupport = (AbstractWorkbenchBrowserSupport) WorkbenchPlugin
217 .createExtension(element, IWorkbenchRegistryConstants.ATT_CLASS);
218 IExtensionTracker extensionTracker = PlatformUI.getWorkbench().getExtensionTracker();
220 extensionTracker.registerHandler(handler, ExtensionTracker
221 .createExtensionPointFilter(getExtensionPoint()));
222 extensionTracker
225 .registerObject(element.getDeclaringExtension(),
226 activeSupport, IExtensionTracker.REF_WEAK);
227 return true;
228 } catch (CoreException e) {
229 WorkbenchPlugin
230 .log("Unable to instantiate browser support" + e.getStatus(), e); }
232 return false;
233 }
234
235 });
236 }
237
238
243 public void setDesiredBrowserSupportId(String desiredBrowserSupportId) {
244 dispose(); this.desiredBrowserSupportId = desiredBrowserSupportId;
246 }
247
248
251 protected void dispose() {
252 activeSupport = null;
253 initialized = false;
254 }
255 }
256 |
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