CommandProvider.java :  » IDE-Eclipse » ui-workbench » org » eclipse » ui » internal » quickaccess » Java Open Source

/*******************************************************************************
 * Copyright (c) 2006, 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
 *******************************************************************************/

package org.eclipse.ui.internal.quickaccess;

import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import org.eclipse.core.commands.Command;
import org.eclipse.core.commands.ParameterizedCommand;
import org.eclipse.core.commands.common.NotDefinedException;
import org.eclipse.core.expressions.IEvaluationContext;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.commands.ICommandService;
import org.eclipse.ui.handlers.IHandlerService;
import org.eclipse.ui.internal.IWorkbenchGraphicConstants;
import org.eclipse.ui.internal.WorkbenchImages;

/**
 * @since 3.3
 * 
 */
public class CommandProvider extends QuickAccessProvider {

  private Map idToElement;
  private IEvaluationContext contextSnapshot;
  private IHandlerService handlerService;
  
  public CommandProvider() {
    // initialize eagerly
    saveApplicationContext();
    getElements();
  }

  public String getId() {
    return "org.eclipse.ui.commands"; //$NON-NLS-1$
  }

  public QuickAccessElement getElementForId(String id) {
    getElements();
    return (CommandElement) idToElement.get(id);
  }

  public QuickAccessElement[] getElements() {
    if (idToElement == null) {
      idToElement = new HashMap();
      ICommandService commandService = (ICommandService) PlatformUI
          .getWorkbench().getService(ICommandService.class);
      final Collection commandIds = commandService.getDefinedCommandIds();
      final Iterator commandIdItr = commandIds.iterator();
      while (commandIdItr.hasNext()) {
        final String currentCommandId = (String) commandIdItr.next();
        final Command command = commandService
            .getCommand(currentCommandId);
        if (command != null && command.isHandled()
            && command.isEnabled()) {
          try {
            Collection combinations = ParameterizedCommand
                .generateCombinations(command);
            for (Iterator it = combinations.iterator(); it
                .hasNext();) {
              ParameterizedCommand pc = (ParameterizedCommand) it.next();
              String id = pc.serialize();
              idToElement.put(id,
                  new CommandElement(pc, id, this));
            }
          } catch (final NotDefinedException e) {
            // It is safe to just ignore undefined commands.
          }
        }
      }
    }
    return (QuickAccessElement[]) idToElement.values().toArray(
        new QuickAccessElement[idToElement.values().size()]);
  }

  public ImageDescriptor getImageDescriptor() {
    return WorkbenchImages
        .getImageDescriptor(IWorkbenchGraphicConstants.IMG_OBJ_NODE);
  }

  public String getName() {
    return QuickAccessMessages.QuickAccess_Commands;
  }
  
  private void saveApplicationContext() {
    handlerService = (IHandlerService) PlatformUI.getWorkbench().getService(IHandlerService.class);
    contextSnapshot = handlerService.createContextSnapshot(true);
  }
  
  IHandlerService getHandlerService() {
    return handlerService;
  }
  
  IEvaluationContext getContextSnapshot() {
    return contextSnapshot;
  }
}