LaunchConfigurationTreeContentProvider.java

/*******************************************************************************
 * Copyright (c) 2009 Borland Software 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:
 *     Borland Software Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.m2m.internal.qvt.oml.runtime.ui.ant;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.debug.core.DebugPlugin;
import org.eclipse.debug.core.ILaunchConfiguration;
import org.eclipse.debug.core.ILaunchConfigurationType;
import org.eclipse.debug.core.ILaunchManager;
import org.eclipse.jface.dialogs.ErrorDialog;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.IPluginContribution;
import org.eclipse.ui.activities.WorkbenchActivityHelper;

/**
 * Content provider for representing launch configuration types & launch
 * configurations in a tree.
 */
class LaunchConfigurationTreeContentProvider implements ITreeContentProvider {

	/**
	 * Empty Object array
	 */
	private static final Object[] EMPTY_ARRAY = new Object[0];

	/**
	 * The mode in which the tree is being shown, one of <code>RUN_MODE</code>
	 * or <code>DEBUG_MODE</code> defined in <code>ILaunchManager</code>.
	 * If this is <code>null</code>, then it means both modes are being
	 * shown.
	 */
	private String fMode;

	/**
	 * The Shell context
	 */
	private Shell fShell;

	public LaunchConfigurationTreeContentProvider(String mode, Shell shell) {
		setMode(mode);
		setShell(shell);
	}

	/**
	 * Actual launch configurations have no children. Launch configuration types
	 * have all configurations of that type as children, minus any
	 * configurations that are marked as private.
	 * <p>
	 * In 2.1, the <code>category</code> attribute was added to launch config
	 * types. The debug UI only displays those configs that do not specify a
	 * category.
	 * </p>
	 * 
	 * @see org.eclipse.jface.viewers.ITreeContentProvider#getChildren(java.lang.Object)
	 */
	public Object[] getChildren(Object parentElement) {
		if (parentElement instanceof ILaunchConfiguration) {
			return EMPTY_ARRAY;
		} else if (parentElement instanceof ILaunchConfigurationType) {
			try {
				ILaunchConfigurationType type = (ILaunchConfigurationType) parentElement;
				return getLaunchManager().getLaunchConfigurations(type);
			} catch (CoreException e) {
				errorDialog(getShell(), e.getStatus());
			}
		} else {
			return getLaunchManager().getLaunchConfigurationTypes();
		}
		return EMPTY_ARRAY;
	}

	public Object getParent(Object element) {
		if (element instanceof ILaunchConfiguration) {
			if (!((ILaunchConfiguration) element).exists()) {
				return null;
			}
			try {
				return ((ILaunchConfiguration) element).getType();
			} catch (CoreException e) {
				errorDialog(getShell(), e.getStatus());
			}
		} else if (element instanceof ILaunchConfigurationType) {
			return ResourcesPlugin.getWorkspace().getRoot();
		}
		return null;
	}

	public boolean hasChildren(Object element) {
		if (element instanceof ILaunchConfiguration) {
			return false;
		}
		return getChildren(element).length > 0;
	}

	/**
	 * Return only the launch configuration types that support the current mode
	 * AND are marked as 'public'.
	 * 
	 * @see org.eclipse.jface.viewers.IStructuredContentProvider#getElements(java.lang.Object)
	 */
	public Object[] getElements(Object inputElement) {
		ILaunchConfigurationType[] allTypes = getLaunchManager().getLaunchConfigurationTypes();
		return filterTypes(allTypes).toArray();
	}

	/**
	 * Returns a list containing the given types minus any types that should not
	 * be visible. A type should not be visible if it doesn't match the current
	 * mode or if it matches a disabled activity.
	 * 
	 * @param allTypes
	 *            the types
	 * @return the given types minus any types that should not be visible.
	 */
	private List<ILaunchConfigurationType> filterTypes(ILaunchConfigurationType[] allTypes) {
		List<ILaunchConfigurationType> filteredTypes = new ArrayList<ILaunchConfigurationType>();
		String mode = getMode();
		LaunchConfigurationTypeContribution contribution;
		for (int i = 0; i < allTypes.length; i++) {
			ILaunchConfigurationType type = allTypes[i];
			contribution = new LaunchConfigurationTypeContribution(type);
			if (isVisible(type, mode) && !WorkbenchActivityHelper.filterItem(contribution)) {
				filteredTypes.add(type);
			}
		}
		return filteredTypes;
	}

	public void dispose() {
	}

	public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
	}

	/**
	 * Return <code>true</code> if the specified launch configuration type
	 * should be visible in the specified mode, <code>false</code> otherwise.
	 */
	private boolean isVisible(ILaunchConfigurationType configType, String mode) {
		if (!configType.isPublic()) {
			return false;
		}
		if (mode == null) {
			return true;
		}
		return configType.supportsMode(mode);
	}

	/**
	 * Convenience method to get the singleton launch manager.
	 */
	private ILaunchManager getLaunchManager() {
		return DebugPlugin.getDefault().getLaunchManager();
	}

	private void setMode(String mode) {
		fMode = mode;
	}

	private String getMode() {
		return fMode;
	}

	private void setShell(Shell shell) {
		fShell = shell;
	}

	private Shell getShell() {
		return fShell;
	}

	/**
	 * Utility method with conventions
	 */
	private static void errorDialog(Shell shell, IStatus s) {
		ErrorDialog.openError(shell, Messages.LaunchConfigError_title, Messages.LaunchConfigError_msg, s);
	}

	/**
	 * A plug-in contribution (UI element) which contains a launch configuration
	 * type (Core element). Plug-in contributions are passed to the workbench
	 * activity support to filter elements from the UI.
	 */
	private static class LaunchConfigurationTypeContribution implements IPluginContribution {

		protected ILaunchConfigurationType type;

		/**
		 * Creates a new plug-in contribution for the given type
		 * 
		 * @param type
		 *            the launch configuration type
		 */
		public LaunchConfigurationTypeContribution(ILaunchConfigurationType type) {
			this.type = type;
		}

		public String getLocalId() {
			return type.getIdentifier();
		}

		public String getPluginId() {
			return type.getPluginIdentifier();
		}
	}
}