/*******************************************************************************
* Copyright (c) 2000, 2008 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
* Jan-Hendrik Diederich, Bredex GmbH - bug 201052
* Oakland Software (Francis Upton) <francisu@ieee.org> - bug 223808
*******************************************************************************/
package org.eclipse.ui.internal.dialogs;
import java.lang.ref.SoftReference;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import org.eclipse.core.expressions.EvaluationContext;
import org.eclipse.core.expressions.EvaluationResult;
import org.eclipse.core.expressions.Expression;
import org.eclipse.core.expressions.ExpressionConverter;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.preference.PreferenceNode;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.ui.IActionFilter;
import org.eclipse.ui.IPluginContribution;
import org.eclipse.ui.IWorkbenchPropertyPage;
import org.eclipse.ui.SelectionEnabler;
import org.eclipse.ui.internal.IWorkbenchConstants;
import org.eclipse.ui.internal.LegacyResourceSupport;
import org.eclipse.ui.internal.WorkbenchPlugin;
import org.eclipse.ui.internal.registry.CategorizedPageRegistryReader;
import org.eclipse.ui.internal.registry.IWorkbenchRegistryConstants;
import org.eclipse.ui.internal.registry.PropertyPagesRegistryReader;
import org.eclipse.ui.internal.util.Util;
import org.eclipse.ui.model.IWorkbenchAdapter;
import org.eclipse.ui.plugin.AbstractUIPlugin;
/**
* This property page contributor is created from page entry in the registry.
* Since instances of this class are created by the workbench, there is no
* danger of premature loading of plugins.
*/
public class RegistryPageContributor implements IPropertyPageContributor,
IAdaptable,
IPluginContribution
{
private static final String CHILD_ENABLED_WHEN = "enabledWhen"; //$NON-NLS-1$
private String pageId;
/**
* The list of subpages (immediate children) of this node (element type:
* <code>RegistryPageContributor</code>).
*/
private Collection subPages = new ArrayList();
private boolean adaptable = false;
private IConfigurationElement pageElement;
private SoftReference filterProperties;
private Expression enablementExpression;
/**
* PropertyPageContributor constructor.
*
* @param pageId
* the id
* @param element
* the element
*/
public RegistryPageContributor(String pageId, IConfigurationElement element) {
this.pageId = pageId;
this.pageElement = element;
adaptable = Boolean
.valueOf(
pageElement
.getAttribute(PropertyPagesRegistryReader.ATT_ADAPTABLE))
.booleanValue();
initializeEnablement(element);
}
/*
* (non-Javadoc)
*
* @see org.eclipse.ui.internal.dialogs.IPropertyPageContributor#contributePropertyPage(org.eclipse.ui.internal.dialogs.PropertyPageManager,
* java.lang.Object)
*/
public PreferenceNode contributePropertyPage(PropertyPageManager mng,
Object element) {
PropertyPageNode node = new PropertyPageNode(this, element);
if (IWorkbenchConstants.WORKBENCH_PROPERTIES_PAGE_INFO.equals(node.getId()))
node.setPriority(-1);
return node;
}
/**
* Creates the page based on the information in the configuration element.
*
* @param element
* the adaptable element
* @return the property page
* @throws CoreException
* thrown if there is a problem creating the apge
*/
public IWorkbenchPropertyPage createPage(Object element)
throws CoreException {
IWorkbenchPropertyPage ppage = null;
ppage = (IWorkbenchPropertyPage) WorkbenchPlugin.createExtension(
pageElement, IWorkbenchRegistryConstants.ATT_CLASS);
ppage.setTitle(getPageName());
Object adapted = element;
if (adaptable) {
adapted = getAdaptedElement(element);
if (adapted == null) {
String message = "Error adapting selection to Property page " + pageId + " is being ignored"; //$NON-NLS-1$ //$NON-NLS-2$
throw new CoreException(new Status(IStatus.ERROR,
WorkbenchPlugin.PI_WORKBENCH, IStatus.ERROR, message,
null));
}
}
if (adapted instanceof IAdaptable)
ppage.setElement((IAdaptable) adapted);
else
ppage.setElement(new AdaptableForwarder(adapted));
return ppage;
}
/**
* Find an adapted element from the receiver.
*
* @param element
* @return the adapted element or <code>null</code> if it could not be
* found.
*/
private Object getAdaptedElement(Object element) {
Object adapted = LegacyResourceSupport.getAdapter(element,
getObjectClass());
if (adapted != null)
return adapted;
return null;
}
/**
* Return the object class name
*
* @return the object class name
*/
public String getObjectClass() {
return pageElement
.getAttribute(PropertyPagesRegistryReader.ATT_OBJECTCLASS);
}
/**
* Returns page icon as defined in the registry.
*
* @return the page icon
*/
public ImageDescriptor getPageIcon() {
String iconName = pageElement
.getAttribute(IWorkbenchRegistryConstants.ATT_ICON);
if (iconName == null)
return null;
return AbstractUIPlugin.imageDescriptorFromPlugin(pageElement
.getNamespaceIdentifier(), iconName);
}
/**
* Returns page ID as defined in the registry.
*
* @return the page id
*/
public String getPageId() {
return pageId;
}
/**
* Returns page name as defined in the registry.
*
* @return the page name
*/
public String getPageName() {
return pageElement.getAttribute(IWorkbenchRegistryConstants.ATT_NAME);
}
/**
* Return true if name filter is not defined in the registry for this page,
* or if name of the selected object matches the name filter.
*/
public boolean isApplicableTo(Object object) {
if (failsEnablement(object))
return false;
// Test name filter
String nameFilter = pageElement
.getAttribute(PropertyPagesRegistryReader.ATT_NAME_FILTER);
if (nameFilter != null) {
String objectName = object.toString();
IWorkbenchAdapter adapter = (IWorkbenchAdapter) Util.getAdapter(object,
IWorkbenchAdapter.class);
if (adapter != null) {
String elementName = adapter.getLabel(object);
if (elementName != null) {
objectName = elementName;
}
}
if (!SelectionEnabler.verifyNameMatch(objectName, nameFilter))
return false;
}
// Test custom filter
if (getFilterProperties() == null)
return true;
IActionFilter filter = null;
// Do the free IResource adapting
Object adaptedObject = LegacyResourceSupport.getAdaptedResource(object);
if (adaptedObject != null) {
object = adaptedObject;
}
filter = (IActionFilter)Util.getAdapter(object, IActionFilter.class);
if (filter != null)
return testCustom(object, filter);
return true;
}
/**
* Return whether or not object fails the enablement criterea.
*
* @param object
* @return boolean <code>true</code> if it fails the enablement test
*/
private boolean failsEnablement(Object object) {
if (enablementExpression == null)
return false;
try {
return enablementExpression.evaluate(
new EvaluationContext(null, object)).equals(
EvaluationResult.FALSE);
} catch (CoreException e) {
WorkbenchPlugin.log(e);
return false;
}
}
/**
* Initialize the enablement expression for this decorator
*/
protected void initializeEnablement(IConfigurationElement definingElement) {
IConfigurationElement[] elements = definingElement
.getChildren(CHILD_ENABLED_WHEN);
if (elements.length == 0)
return;
try {
IConfigurationElement[] enablement = elements[0].getChildren();
if (enablement.length == 0)
return;
enablementExpression = ExpressionConverter.getDefault().perform(
enablement[0]);
} catch (CoreException e) {
WorkbenchPlugin.log(e);
}
}
/**
* Returns whether the object passes a custom key value filter implemented
* by a matcher.
*/
private boolean testCustom(Object object, IActionFilter filter) {
Map filterProperties = getFilterProperties();
if (filterProperties == null)
return false;
Iterator iter = filterProperties.keySet().iterator();
while (iter.hasNext()) {
String key = (String) iter.next();
String value = (String) filterProperties.get(key);
if (!filter.testAttribute(object, key, value))
return false;
}
return true;
}
/*
* @see IObjectContributor#canAdapt()
*/
public boolean canAdapt() {
return adaptable;
}
/**
* Get the id of the category.
*
* @return String
* @since 3.1
*/
public String getCategory() {
return pageElement
.getAttribute(CategorizedPageRegistryReader.ATT_CATEGORY);
}
/**
* Return the children of the receiver.
*
* @return Collection
*/
public Collection getSubPages() {
return subPages;
}
/**
* Add child to the list of children.
*
* @param child
*/
public void addSubPage(RegistryPageContributor child) {
subPages.add(child);
}
private Map getFilterProperties() {
if (filterProperties == null || filterProperties.get() == null) {
Map map = new HashMap();
filterProperties = new SoftReference(map);
IConfigurationElement[] children = pageElement.getChildren();
for (int i = 0; i < children.length; i++) {
processChildElement(map, children[i]);
}
}
return (Map) filterProperties.get();
}
/**
* Get the child with the given id.
*
* @param id
* @return RegistryPageContributor
*/
public Object getChild(String id) {
Iterator iterator = subPages.iterator();
while (iterator.hasNext()) {
RegistryPageContributor next = (RegistryPageContributor) iterator
.next();
if (next.getPageId().equals(id))
return next;
}
return null;
}
/**
* Parses child element and processes it.
*
* @since 3.1
*/
private void processChildElement(Map map, IConfigurationElement element) {
String tag = element.getName();
if (tag.equals(PropertyPagesRegistryReader.TAG_FILTER)) {
String key = element
.getAttribute(PropertyPagesRegistryReader.ATT_FILTER_NAME);
String value = element
.getAttribute(PropertyPagesRegistryReader.ATT_FILTER_VALUE);
if (key == null || value == null)
return;
map.put(key, value);
}
}
/*
* (non-Javadoc)
*
* @see org.eclipse.core.runtime.IAdaptable#getAdapter(java.lang.Class)
* @since 3.1
*/
public Object getAdapter(Class adapter) {
if (adapter.equals(IConfigurationElement.class)) {
return getConfigurationElement();
}
return null;
}
/**
* @return the configuration element
* @since 3.1
*/
IConfigurationElement getConfigurationElement() {
return pageElement;
}
public String getLocalId() {
return pageId;
}
public String getPluginId() {
return pageElement.getContributor().getName();
}
}