/*******************************************************************************
* Copyright (c) 2000, 2008 QNX Software Systems 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.cdt.internal.ui.text.folding;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import org.eclipse.cdt.ui.CUIPlugin;
import org.eclipse.cdt.ui.PreferenceConstants;
import org.eclipse.cdt.ui.text.folding.ICFoldingStructureProvider;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExtensionRegistry;
import org.eclipse.core.runtime.Platform;
public class CFoldingStructureProviderRegistry {
private static final String EXTENSION_POINT= "foldingStructureProviders"; //$NON-NLS-1$
/** The map of descriptors, indexed by their identifiers. */
private Map<String, CFoldingStructureProviderDescriptor> fDescriptors;
/**
* Creates a new instance.
*/
public CFoldingStructureProviderRegistry() {
}
/**
* Returns an array of <code>ICFoldingProviderDescriptor</code> describing
* all extension to the <code>foldingProviders</code> extension point.
*
* @return the list of extensions to the
* <code>quickDiffReferenceProvider</code> extension point.
*/
public CFoldingStructureProviderDescriptor[] getFoldingProviderDescriptors() {
synchronized (this) {
ensureRegistered();
return fDescriptors.values().toArray(new CFoldingStructureProviderDescriptor[fDescriptors.size()]);
}
}
/**
* Returns the folding provider with identifier <code>id</code> or
* <code>null</code> if no such provider is registered.
*
* @param id the identifier for which a provider is wanted
* @return the corresponding provider, or <code>null</code> if none can be
* found
*/
public CFoldingStructureProviderDescriptor getFoldingProviderDescriptor(String id) {
synchronized (this) {
ensureRegistered();
return fDescriptors.get(id);
}
}
/**
* Instantiates and returns the provider that is currently configured in the
* preferences.
*
* @return the current provider according to the preferences
*/
public ICFoldingStructureProvider getCurrentFoldingProvider() {
String id= CUIPlugin.getDefault().getPreferenceStore().getString(PreferenceConstants.EDITOR_FOLDING_PROVIDER);
CFoldingStructureProviderDescriptor desc= getFoldingProviderDescriptor(id);
if (desc != null) {
try {
return desc.createProvider();
} catch (CoreException e) {
CUIPlugin.log(e);
}
}
return null;
}
/**
* Ensures that the extensions are read and stored in
* <code>fDescriptors</code>.
*/
private void ensureRegistered() {
if (fDescriptors == null)
reloadExtensions();
}
/**
* Reads all extensions.
* <p>
* This method can be called more than once in
* order to reload from a changed extension registry.
* </p>
*/
public void reloadExtensions() {
IExtensionRegistry registry= Platform.getExtensionRegistry();
Map<String, CFoldingStructureProviderDescriptor> map= new HashMap<String, CFoldingStructureProviderDescriptor>();
IConfigurationElement[] elements= registry.getConfigurationElementsFor(CUIPlugin.getPluginId(), EXTENSION_POINT);
for (int i= 0; i < elements.length; i++) {
CFoldingStructureProviderDescriptor desc= new CFoldingStructureProviderDescriptor(elements[i]);
map.put(desc.getId(), desc);
}
synchronized(this) {
fDescriptors= Collections.unmodifiableMap(map);
}
}
}