content: /*******************************************************************************
   * 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
   *******************************************************************************/
  package org.eclipse.wst.jsdt.ui.actions;
  
  import java.lang.reflect.InvocationTargetException;
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  
  import org.eclipse.core.resources.IResource;
  import org.eclipse.core.resources.IWorkspaceRunnable;
  import org.eclipse.core.runtime.CoreException;
  import org.eclipse.core.runtime.IProgressMonitor;
  import org.eclipse.core.runtime.SubProgressMonitor;
  import org.eclipse.jface.viewers.IStructuredSelection;
  import org.eclipse.ui.IWorkbenchSite;
  import org.eclipse.ui.PlatformUI;
  import org.eclipse.wst.jsdt.core.IIncludePathEntry;
  import org.eclipse.wst.jsdt.core.IPackageFragmentRoot;
  import org.eclipse.wst.jsdt.core.JavaScriptModelException;
  import org.eclipse.wst.jsdt.internal.corext.util.JavaModelUtil;
  import org.eclipse.wst.jsdt.internal.ui.IJavaHelpContextIds;
  import org.eclipse.wst.jsdt.internal.ui.JavaScriptPlugin;
  import org.eclipse.wst.jsdt.internal.ui.actions.ActionMessages;
  import org.eclipse.wst.jsdt.internal.ui.actions.WorkbenchRunnableAdapter;
  import org.eclipse.wst.jsdt.internal.ui.util.ExceptionHandler;
  
  /**
   * Action to remove package fragment roots from the classpath of its parent
   * project. Currently, the action is applicable to selections containing
   * non-external archives (JAR or zip).
   * 
   * <p>
   * This class may be instantiated; it is not intended to be subclassed.
   * </p>
   * 
   *
   * Provisional API: This class/interface is part of an interim API that is still under development and expected to
   * change significantly before reaching stability. It is being made available at this early stage to solicit feedback
   * from pioneering adopters on the understanding that any code that uses this API will almost certainly be broken
   * (repeatedly) as the API evolves.
   */
  public class RemoveFromClasspathAction extends SelectionDispatchAction {
  
  	/**
  	 * Creates a new <code>RemoveFromClasspathAction</code>. The action requires
  	 * that the selection provided by the site's selection provider is of type
  	 * <code> org.eclipse.jface.viewers.IStructuredSelection</code>.
  	 * 
  	 * @param site the site providing context information for this action
  	 */
  	public RemoveFromClasspathAction(IWorkbenchSite site) {
  		super(site);
  		setText(ActionMessages.RemoveFromClasspathAction_Remove); 
  		setToolTipText(ActionMessages.RemoveFromClasspathAction_tooltip); 
  		PlatformUI.getWorkbench().getHelpSystem().setHelp(this, IJavaHelpContextIds.REMOVE_FROM_CLASSPATH_ACTION);
  	}
  	
  	/* (non-Javadoc)
  	 * Method declared in SelectionDispatchAction
  	 */
  	public void selectionChanged(IStructuredSelection selection) {
  		setEnabled(checkEnabled(selection));
  	}
  	
  	private static boolean checkEnabled(IStructuredSelection selection) {
  		if (selection.isEmpty())
  			return false;
  		for (Iterator iter= selection.iterator(); iter.hasNext();) {
  			if (! canRemove(iter.next()))
  				return false;
  		}
  		return true;
  	}
  	
  	/* (non-Javadoc)
  	 * Method declared in SelectionDispatchAction
  	 */
  	public void run(final IStructuredSelection selection) {
  		try {
  			PlatformUI.getWorkbench().getActiveWorkbenchWindow().run(true, true, new WorkbenchRunnableAdapter(new IWorkspaceRunnable() {
  				public void run(IProgressMonitor pm) throws CoreException {
  					try{
  						IPackageFragmentRoot[] roots= getRootsToRemove(selection);
  						pm.beginTask(ActionMessages.RemoveFromClasspathAction_Removing, roots.length); 
  						for (int i= 0; i < roots.length; i++) {
  							int jCoreFlags= IPackageFragmentRoot.NO_RESOURCE_MODIFICATION | IPackageFragmentRoot.ORIGINATING_PROJECT_INCLUDEPATH;
  							roots[i].delete(IResource.NONE, jCoreFlags, new SubProgressMonitor(pm, 1));
  						}
  					} finally {
  						pm.done();
  					}
  				}
  		}));
  		} catch (InvocationTargetException e) {
  			ExceptionHandler.handle(e, getShell(), 
  					ActionMessages.RemoveFromClasspathAction_exception_dialog_title, 
  					ActionMessages.RemoveFromClasspathAction_Problems_occurred); 
  		} catch (InterruptedException e) {
  			// canceled
  		}
  	}
  	
  	private static IPackageFragmentRoot[] getRootsToRemove(IStructuredSelection selection){
  		List result= new ArrayList(selection.size()); 
  		for (Iterator iter= selection.iterator(); iter.hasNext();) {
  			Object element= iter.next();
  			if (canRemove(element))
  				result.add(element);
  		}
  		return (IPackageFragmentRoot[]) result.toArray(new IPackageFragmentRoot[result.size()]);
  	}	
  
  	private static boolean canRemove(Object element){
  		if (! (element instanceof IPackageFragmentRoot))
  			return false;
  		IPackageFragmentRoot root= (IPackageFragmentRoot)element;
  		try {
  			IIncludePathEntry cpe= root.getRawIncludepathEntry();
  			if (cpe == null || cpe.getEntryKind() == IIncludePathEntry.CPE_CONTAINER)
  				return false; // don't want to remove the container if only a child is selected
  			return true;
  		} catch (JavaScriptModelException e) {
  			if (JavaModelUtil.isExceptionToBeLogged(e))
  				JavaScriptPlugin.log(e);
  		}
  		return false;
  	}	
  }
  
  