MarkerHelper.java

/**
 * <copyright>
 *
 * Copyright (c) 2006, 2010 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 - Initial API and implementation
 *
 * </copyright>
 *
 * $Id: MarkerHelper.java,v 1.9 2007/06/14 18:32:41 emerks Exp $
 */
package net.enilink.komma.common.ui;

import java.util.Collections;
import java.util.List;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IMarker;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.Path;
import org.eclipse.ui.IEditorInput;

import net.enilink.komma.common.util.Diagnostic;
import net.enilink.komma.core.URI;

/**
 * Provides methods to simplify the work with {@link IMarker}s. The main goal is
 * to simplify the creation of markers using the information described in
 * {@link Diagnostic}s.
 * 
 */
public class MarkerHelper {
	protected String getMarkerID() {
		return "org.eclipse.core.resources.problemmarker";
	}

	protected IFile getFile(Object datum) {
		IFile file = EclipseUtil.getFile(datum);
		if (file != null) {
			return file;
		}
		if (datum instanceof Diagnostic) {
			return getFile((Diagnostic) datum);
		}
		return null;
	}

	protected IFile getFile(Diagnostic diagnostic) {
		List<?> data = diagnostic.getData();
		if (data != null) {
			for (Object datum : data) {
				IFile result = getFile(datum);
				if (result != null) {
					return result;
				}
			}
		}
		return null;
	}

	protected IFile getFile(URI uri) {
		String platformResourceString = uri.toPlatformString(true);
		return platformResourceString != null ? ResourcesPlugin.getWorkspace()
				.getRoot().getFile(new Path(platformResourceString)) : null;
	}

	/**
	 * <p>
	 * Creates a marker based on the information available in the specified
	 * diagnostic. The marker's id is defined by {@link #getMarkerID()}.
	 * </p>
	 * <p>
	 * The default implementation looks in the diagnostic's data array for
	 * objects that would allow an IFile to be computed
	 * </p>
	 * 
	 * @param diagnostic
	 * @throws CoreException
	 */
	public boolean createMarkers(Diagnostic diagnostic) throws CoreException {
		boolean created = false;
		if (diagnostic.getMessage() == null) {
			for (Diagnostic childDiagnostic : diagnostic.getChildren()) {
				created |= createMarkers(childDiagnostic);
			}
		} else {
			for (Diagnostic childDiagnostic : diagnostic.getChildren()) {
				created |= createMarkers(getFile(childDiagnostic),
						childDiagnostic, diagnostic);
			}
		}
		if (!created) {
			IResource resource = getFile(diagnostic);
			if (resource != null) {
				created = createMarkers(resource, diagnostic, null);
			}
		}
		return created;
	}

	protected boolean createMarkers(IResource resource, Diagnostic diagnostic,
			Diagnostic parentDiagnostic) throws CoreException {
		if (resource != null && resource.exists()) {
			IMarker marker = resource.createMarker(getMarkerID());
			int severity = diagnostic.getSeverity();
			if (severity < Diagnostic.WARNING) {
				marker.setAttribute(IMarker.SEVERITY, IMarker.SEVERITY_INFO);
			} else if (severity < Diagnostic.ERROR) {
				marker.setAttribute(IMarker.SEVERITY, IMarker.SEVERITY_WARNING);
			} else {
				marker.setAttribute(IMarker.SEVERITY, IMarker.SEVERITY_ERROR);
			}

			String message = composeMessage(diagnostic, parentDiagnostic);
			if (message != null) {
				marker.setAttribute(IMarker.MESSAGE, message);
			}

			adjustMarker(marker, diagnostic, parentDiagnostic);
			return true;
		}
		return false;
	}

	/**
	 * Clients should override this method to update the marker associated with
	 * the diagnostic.
	 * 
	 * @param marker
	 *            the marker to be updated.
	 * @param diagnostic
	 *            the diagnostic associated with the marker.
	 * @param parentDiagnostic
	 *            the parent of the diagnostic, if any.
	 * @throws CoreException
	 */
	protected void adjustMarker(IMarker marker, Diagnostic diagnostic,
			Diagnostic parentDiagnostic) throws CoreException {
		// Subclasses may override
	}

	/**
	 * Returns the message that will be used with the marker associated with the
	 * given diagnostic.
	 * 
	 * @param diagnostic
	 *            the diagnostic.
	 * @param parentDiagnostic
	 *            the parent of the diagnostic, if any.
	 * @return the message that will be used with the marker associated with the
	 *         given diagnostic.
	 */
	protected String composeMessage(Diagnostic diagnostic,
			Diagnostic parentDiagnostic) {
		return diagnostic.getMessage();
	}

	/**
	 * Returns whether the a maker with id equals to the return of
	 * {@link #getMarkerID()} is available in the IResource computed from the
	 * specified object.
	 * 
	 * @param object
	 * @return boolean
	 */
	public boolean hasMarkers(Object object) {
		return hasMarkers(object, false, IResource.DEPTH_ZERO);
	}

	public boolean hasMarkers(Object object, boolean includeSubtypes, int depth) {
		return hasMarkers(getFile(object), includeSubtypes, depth);
	}

	protected boolean hasMarkers(IResource resource, boolean includeSubtypes,
			int depth) {
		if (resource != null && resource.exists()) {
			try {
				IMarker[] markers = resource.findMarkers(getMarkerID(),
						includeSubtypes, depth);
				return markers.length > 0;
			} catch (CoreException e) {
				// Ignore
			}
		}
		return false;
	}

	/**
	 * Deletes a maker with id equals to the return of {@link #getMarkerID()}
	 * from the IResource computed from the specified object.
	 * 
	 * @param object
	 */
	public void deleteMarkers(Object object) {
		deleteMarkers(object, false, IResource.DEPTH_ZERO);
	}

	public void deleteMarkers(Object object, boolean includeSubtypes, int depth) {
		deleteMarkers(getFile(object), includeSubtypes, depth);
	}

	protected void deleteMarkers(IResource resource, boolean includeSubtypes,
			int depth) {
		if (resource != null && resource.exists()) {
			try {
				resource.deleteMarkers(getMarkerID(), includeSubtypes, depth);
			} catch (CoreException e) {
				CommonUIPlugin.INSTANCE.log(e);
			}
		}
	}

	public IEditorInput getEditorInput(Object object) {
		IFile file = getFile(object);
		if (file != null) {
			return EclipseUtil.createEditorInput(file);
		} else {
			return null;
		}
	}

	/**
	 * @since 2.3
	 */
	public List<?> getTargetObjects(Object object, IMarker marker) {
		return Collections.EMPTY_LIST;
	}
}