plugins/org.eclipse.ease/src/org/eclipse/ease/tools/ResourceTools.java - ease/org.eclipse.ease.core - Git at Google

 /*******************************************************************************
  * Copyright (c) 2014 Christian Pontesegger 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:
  *     Christian Pontesegger - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ease.tools;

 import java.io.BufferedInputStream;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.Reader;
 import java.net.MalformedURLException;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;

 import org.eclipse.core.resources.IContainer;
 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IFolder;
 import org.eclipse.core.resources.IProject;
 import org.eclipse.core.resources.IResource;
 import org.eclipse.core.resources.IWorkspaceRoot;
 import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IPath;
 import org.eclipse.core.runtime.NullProgressMonitor;
 import org.eclipse.core.runtime.Path;
 import org.eclipse.ease.Activator;
 import org.eclipse.ease.Logger;
 import org.eclipse.ease.urlhandler.WorkspaceURLConnection;

 public final class ResourceTools {

 	/**
 	 * InputStream delegating all tasks to a base stream. The only method not forwarded is close().
 	 */
 	public static class NonClosingInputStream extends InputStream {

 		private final InputStream fBaseStream;

 		public NonClosingInputStream(InputStream baseStream) {
 			fBaseStream = baseStream;
 		}

 		@Override
 		public int read() throws IOException {
 			return fBaseStream.read();
 		}

 		@Override
 		public int available() throws IOException {
 			return fBaseStream.available();
 		}

 		@Override
 		public long skip(long n) throws IOException {
 			return fBaseStream.skip(n);
 		}

 		@Override
 		public boolean markSupported() {
 			return fBaseStream.markSupported();
 		}

 		@Override
 		public synchronized void mark(int readlimit) {
 			fBaseStream.mark(readlimit);
 		}

 		@Override
 		public synchronized void reset() throws IOException {
 			fBaseStream.reset();
 		}

 		@Override
 		public int read(byte[] b, int off, int len) throws IOException {
 			return fBaseStream.read(b, off, len);
 		}

 		@Override
 		public int read(byte[] b) throws IOException {
 			return fBaseStream.read(b);
 		}
 	}

 	private static final String PROJECT_SCHEME = "project";
 	private static final String PROJECT_PREFIX = PROJECT_SCHEME + "://";

 	private static final String WORKSPACE_SCHEME = "workspace";
 	private static final String WORKSPACE_PREFIX = WORKSPACE_SCHEME + "://";

 	private static final String FILE_SCHEME = "file";
 	private static final String FILE_PREFIX = FILE_SCHEME + "://";

 	private static final String SCRIPT_SCHEME = "script";

 	private static final Pattern WINDOWS_LOCAL_FILE_PATTERN = Pattern.compile("(?:file:///?)?([A-Z]:[/\\\\].*)");
 	private static final Pattern WINDOWS_NETWORK_FILE_PATTERN = Pattern.compile("(?:file\\:)?((?://|\\\\\\\\)[^:/][^:]*)");

 	/** Virtual file indicating a file system root on windows. Needed as windows does not have a real root file object. */
 	public static final Object VIRTUAL_WINDOWS_ROOT = new File("/");

 	/**
 	 * @deprecated
 	 */
 	@Deprecated
 	private ResourceTools() {
 	}

 	/**
 	 * Resolve to an existing File/IResource/URI/URL. For relative locations the parent object location is taken into account.
 	 *
 	 * @param location
 	 *            location to resolve
 	 * @param parent
 	 *            parent location to resolve from (needs to be absolute)
 	 * @return resource or <code>null</code>
 	 */
 	public static Object resolve(Object location, Object parent) {
 		if ((location instanceof File) || (location instanceof IResource) || (location instanceof URI) || (location instanceof URL))
 			return location;

 		if ((location == null) || (location.toString().trim().isEmpty())) {
 			final Object resolvedParent = resolve(parent);
 			if (resolvedParent instanceof IFile)
 				return ((IFile) resolvedParent).getParent();

 			if ((resolvedParent instanceof File) && (((File) resolvedParent).isFile()))
 				return ((File) resolvedParent).getParentFile();

 			return resolvedParent;
 		}

 		final String locationStr = location.toString();
 		if (isAbsolute(locationStr))
 			return resolve(location);

 		// simple checks done, now we need the parent
 		parent = resolve(parent);
 		if (!exists(parent))
 			return null;

 		if (parent instanceof IResource) {
 			// resolve within workspace

 			if (locationStr.startsWith(PROJECT_PREFIX)) {
 				// "project://..." location
 				final String targetPath = WORKSPACE_PREFIX + ((IResource) parent).getProject().getName() + "/" + locationStr.substring(PROJECT_PREFIX.length());
 				return resolve(targetPath);
 			}

 			// pure relative location
 			final IPath parentPath = (parent instanceof IFile) ? ((IResource) parent).getParent().getFullPath() : ((IResource) parent).getFullPath();
 			final IPath locationPath = new Path(locationStr);

 			IPath targetPath;
 			if (locationPath.segmentCount() > parentPath.segmentCount()) {
 				// check for special case when relative path steps out of workspace hierarchy
 				targetPath = appendPath(parentPath, locationPath);
 			} else
 				targetPath = parentPath.append(locationPath);

 			if (targetPath != null) {
 				final Object resolvedTarget = resolve(WORKSPACE_PREFIX + targetPath.makeRelative().toPortableString());
 				if (resolvedTarget != null)
 					return resolvedTarget;
 			}

 			// could not resolve within the workspace, try within the file system
 			parent = toFile(parent);
 		}

 		if (parent instanceof File) {
 			// resolve within file system
 			final Path parentPath = new Path(
 					(((File) parent).isFile()) ? ((File) parent).getParentFile().getAbsolutePath() : ((File) parent).getAbsolutePath());

 			final IPath targetPath = parentPath.append(new Path(locationStr));
 			return targetPath.toFile();
 		}

 		if (parent instanceof URL) {
 			try {
 				parent = ((URL) parent).toURI();
 			} catch (final URISyntaxException e) {
 				// TODO handle this exception (but for now, at least know it happened)
 				throw new RuntimeException(e);
 			}
 		}

 		if (parent instanceof URI) {
 			return ((URI) parent).resolve(locationStr);
 		}

 		return null;
 	}

 	/**
 	 * Manually add segment by segment to a path to make sure we do not step back outside of the given parent path. Tries to detect cases like this one:
 	 * '/some/path/../../..' which do not get resolved correctly by path.append().
 	 *
 	 * @param parentPath
 	 *            parent path
 	 * @param locationPath
 	 *            relative path to append
 	 * @return appended path or <code>null</code> in case we leave the context
 	 */
 	private static IPath appendPath(IPath parentPath, IPath locationPath) {
 		if (locationPath.segmentCount() > 0) {
 			final IPath newParent = parentPath.append(locationPath.segment(0));
 			if (parentPath.equals(newParent))
 				return null;

 			return appendPath(newParent, locationPath.removeFirstSegments(1));

 		} else
 			return parentPath;
 	}

 	/**
 	 * Check whether a resource exists. Works only for IResource, File, URI, URL objects. Does not try to resolve the given location.
 	 *
 	 * @param resource
 	 *            resource to query for
 	 * @return <code>true</code> if resource exists or is of type URI or URL
 	 */
 	public static boolean exists(Object resource) {
 		if (resource instanceof IResource)
 			return ((IResource) resource).exists();

 		if (resource instanceof File)
 			return ((File) resource).exists();

 		if ((resource instanceof URI) || (resource instanceof URL))
 			return true;

 		return false;
 	}

 	/**
 	 * Check if a resource exists and is of type file. Does not resolve the resource.
 	 *
 	 * @param resource
 	 *            {@link File} or {@link IResource} object
 	 * @return <code>true</code> when resource is a file
 	 */
 	public static boolean isFile(Object resource) {
 		if (exists(resource)) {
 			if (resource instanceof IFile)
 				return true;

 			if ((resource instanceof File) && (((File) resource).isFile()))
 				return true;
 		}

 		return false;
 	}

 	/**
 	 * Check if a resource exists and is of type folder. For the eclipse workspace this check is also true for the workspace root and project locations. Does
 	 * not resolve the resource.
 	 *
 	 * @param resource
 	 *            {@link File} or {@link IResource} object
 	 * @return <code>true</code> when resource is a folder
 	 */
 	public static boolean isFolder(Object resource) {
 		if (exists(resource)) {
 			if (resource instanceof IContainer)
 				return true;

 			if ((resource instanceof File) && (((File) resource).isDirectory()))
 				return true;
 		}

 		return false;
 	}

 	/**
 	 * Resolve to an existing File/IResource/URI/URL.
 	 *
 	 * @param location
 	 *            location to resolve
 	 * @return resource or <code>null</code>
 	 */
 	public static Object resolve(Object location) {
 		if ((location instanceof File) || (location instanceof IResource) || (location instanceof URI) || (location instanceof URL))
 			return location;

 		if ((location == null) || (location.toString().trim().isEmpty()))
 			return null;

 		final String locationStr = location.toString();
 		if (isAbsolute(locationStr)) {
 			if (locationStr.startsWith(WORKSPACE_PREFIX)) {
 				if (WORKSPACE_PREFIX.equals(locationStr))
 					return getWorkspace();

 				// workspace file
 				final IPath path = new Path(locationStr.substring(WORKSPACE_PREFIX.length()));

 				if (path.isEmpty())
 					// user stepped back into workspace root
 					return getWorkspace();

 				final IProject project = getWorkspace().getProject(path.segment(0));
 				if (project != null) {
 					if (path.segmentCount() == 1)
 						return project;

 					final IFolder folder = project.getFolder(path.removeFirstSegments(1));
 					if (folder.exists())
 						return folder;

 					return project.getFile(path.removeFirstSegments(1));
 				}

 			} else if (locationStr.startsWith(FILE_PREFIX)) {
 				if (isWindows()) {
 					Matcher matcher = WINDOWS_LOCAL_FILE_PATTERN.matcher(locationStr);
 					if (matcher.matches())
 						return new File(matcher.group(1));

 					matcher = WINDOWS_NETWORK_FILE_PATTERN.matcher(locationStr);
 					if (matcher.matches())
 						return new File(matcher.group(1));

 					else if (("file:///".equals(locationStr)) || ("file://".equals(locationStr)))
 						return VIRTUAL_WINDOWS_ROOT;

 					// giving up
 					return null;

 				} else {
 					if (locationStr.startsWith("file:///"))
 						return new File(locationStr.substring(7));

 					else if (locationStr.startsWith("file://"))
 						return new File(locationStr.substring(6));

 					else
 						return new File(locationStr);
 				}

 			} else if (locationStr.startsWith(SCRIPT_SCHEME)) {
 				// script scheme needs to resolve to URLs to be usable
 				try {
 					return new URL(locationStr);
 				} catch (final MalformedURLException e1) {
 					// TODO handle this exception (but for now, at least know it happened)
 					throw new RuntimeException(e1);
 				}

 			} else if ((locationStr.contains(":/")) && (locationStr.indexOf(":/") != 1)) {
 				// the check: (locationStr.indexOf(":/") != 1) eliminates windows file 'URIs' like C:/mydata/...
 				// simple check for URI schemes
 				try {
 					return createURI(locationStr);

 				} catch (final MalformedURLException e) {
 					// could be thrown for unknown protocols like svn://

 					// fallback, no more escaping of spaces
 					return URI.create(locationStr);

 				} catch (final URISyntaxException e) {
 					// TODO handle this exception (but for now, at least know it happened)
 					throw new RuntimeException(e);
 				}

 			} else {
 				// quite likely an absolute path into the file system
 				return new File(locationStr);
 			}
 		}

 		return null;
 	}

 	public static boolean isWindows() {
 		return System.getProperty("os.name").toLowerCase().startsWith("windows");
 	}

 	/**
 	 * Correctly escapes spaces in URIs.
 	 *
 	 * @param address
 	 *            address to create URI for
 	 * @return URI
 	 * @throws MalformedURLException
 	 * @throws URISyntaxException
 	 */
 	public static URI createURI(String address) throws MalformedURLException, URISyntaxException {
 		final URL url = new URL(address);
 		return new URI(url.getProtocol(), url.getUserInfo(), url.getHost(), url.getPort(), url.getPath(), url.getQuery(), url.getRef());
 	}

 	/**
 	 * Get the workspace root.
 	 *
 	 * @return workspace root
 	 */
 	private static IWorkspaceRoot getWorkspace() {
 		return ResourcesPlugin.getWorkspace().getRoot();
 	}

 	/**
 	 * Verifies if a location is provided in absolute form.
 	 *
 	 * @param location
 	 *            location string
 	 * @return <code>true</code> for absolute locations
 	 */
 	public static boolean isAbsolute(String location) {
 		if (location.startsWith(PROJECT_PREFIX))
 			return false;

 		// simple check for URI style
 		if (location.contains(":/"))
 			return true;

 		// check for windows files
 		if (WINDOWS_LOCAL_FILE_PATTERN.matcher(location).matches())
 			return true;

 		if (WINDOWS_NETWORK_FILE_PATTERN.matcher(location).matches())
 			return true;

 		return new Path(location).isAbsolute();
 	}

 	/**
 	 * Provides the project relative URI for a given workspace resource. The provided location will be of type 'project://...'.
 	 *
 	 * @param resource
 	 *            resource to get relative URI for.
 	 * @return project relative location
 	 */
 	public static String toProjectRelativeLocation(final IResource resource) {
 		return PROJECT_SCHEME + "://" + resource.getProjectRelativePath().toPortableString();
 	}

 	/**
 	 * Resolve a given location to an absolute location URI. When <i>location</i> is not a string, we create an absolute string representation of the given
 	 * location.
 	 *
 	 * @param location
 	 *            (relative) location
 	 * @param parent
 	 *            parent object to resolve from
 	 * @return resolved location string or <code>null</code>
 	 */
 	public static String toAbsoluteLocation(final Object location, final Object parent) {

 		// try to resolve file
 		final Object file = resolve(location, parent);
 		if (file instanceof IResource)
 			return WorkspaceURLConnection.SCHEME + ":/" + ((IResource) file).getFullPath().toPortableString();

 		else if (file instanceof File) {
 			if (isWindows()) {
 				// change backslashes to forward slashes
 				final String filePath = ((File) file).toString().replaceAll("\\\\", "/");
 				if (filePath.startsWith("//"))
 					return "file://" + filePath.substring(2);

 				return "file:///" + filePath;

 			} else
 				return "file://" + ((File) file).toString();
 		}

 		else if (file != null)
 			return file.toString();

 		// nothing to resolve, return null
 		return null;
 	}

 	/**
 	 * Create a relative path from one resource to another.
 	 *
 	 * @param resource
 	 *            resource to create a relative path for
 	 * @param parent
 	 *            resource to create relative path from
 	 * @return relative path for <i>resource</i>
 	 */
 	public static String toRelativeLocation(Object resource, Object parent) {
 		resource = resolve(resource);
 		if (resource == null)
 			return null;

 		parent = resolve(parent);
 		if (parent == null)
 			return null;

 		if (isFile(parent)) {
 			if (parent instanceof IFile)
 				parent = ((IFile) parent).getParent();
 			else if (parent instanceof File)
 				parent = ((File) parent).getParentFile();
 		}

 		IPath parentPath;
 		IPath resourcePath;

 		if ((resource instanceof IResource) && (parent instanceof IResource)) {
 			// within workspace
 			parentPath = ((IResource) parent).getFullPath();
 			resourcePath = ((IResource) resource).getFullPath();

 		} else {
 			// within file system
 			resource = toFile(resource);
 			parent = toFile(parent);

 			try {
 				parentPath = new Path(((File) parent).getCanonicalPath());
 				resourcePath = new Path(((File) resource).getCanonicalPath());
 				if (!parentPath.getDevice().equals(resourcePath.getDevice()))
 					// different devices, no relative path possible
 					return null;
 			} catch (final IOException e) {
 				// could not get canonical path, giving up
 				return null;
 			}
 		}

 		// concatenate paths
 		final int matchingSegments = parentPath.matchingFirstSegments(resourcePath);
 		parentPath = parentPath.removeFirstSegments(matchingSegments);
 		resourcePath = resourcePath.removeFirstSegments(matchingSegments);

 		for (int index = 0; index < parentPath.segmentCount(); index++)
 			resourcePath = new Path("..").append(resourcePath);

 		return resourcePath.toPortableString();
 	}

 	/**
 	 * Get the content of a resource location as {@link InputStream}.
 	 *
 	 * @param location
 	 *            location to read from
 	 * @return {@link InputStream} or <code>null</code>
 	 */
 	public static InputStream getInputStream(final Object location) {
 		if (location instanceof InputStream)
 			return (InputStream) location;

 		try {
 			final Object resource = resolve(location);
 			if (resource instanceof IFile)
 				return ((IFile) resource).getContents();

 			if (resource instanceof File)
 				return new FileInputStream((File) resource);

 			if (resource instanceof URI)
 				return ((URI) resource).toURL().openStream();

 			// last resort: try to create a URL directly
 			if (location != null)
 				return new URL(location.toString()).openStream();

 		} catch (final Exception e) {
 			// cannot open stream
 			Logger.error(Activator.PLUGIN_ID, "Cannot open stream for \"" + location + "\"", e);
 		}

 		return null;
 	}

 	/**
 	 * Reads from a resource into a string. Does not throw any exceptions, instead returns <code>null</code> in case of errors and logs the error to the system
 	 * logger.
 	 *
 	 * @param location
 	 *            location to look up
 	 * @return content or <code>null</code> in case of error
 	 */
 	public static String toString(final Object location) {
 		try {
 			final InputStream inputStream = new BufferedInputStream(getInputStream(location));
 			return StringTools.toString(inputStream);
 		} catch (final IOException e) {
 			Logger.error(Activator.PLUGIN_ID, "Cannot read from resource \"" + location + "\"", e);
 		}

 		return null;
 	}

 	/**
 	 * Convert an input stream to a string.
 	 *
 	 * @param stream
 	 *            input string to read from
 	 * @return string containing stream data
 	 * @throws IOException
 	 *             thrown on problems with input stream
 	 */
 	public static String toString(final InputStream stream) throws IOException {
 		if (stream == null)
 			return null;

 		return toString(new InputStreamReader(stream));
 	}

 	/**
 	 * Read characters from a {@link Reader} and return its string representation. Can be used to convert an {@link InputStream} to a string.
 	 *
 	 * @param reader
 	 *            reader to read from
 	 * @return string content of reader
 	 * @throws IOException
 	 *             when reader is not accessible
 	 */
 	public static String toString(final Reader reader) throws IOException {
 		if (reader == null)
 			return null;

 		final StringBuffer out = new StringBuffer();

 		final char[] buffer = new char[1024];
 		int bytes = 0;
 		do {
 			bytes = reader.read(buffer);
 			if (bytes > 0)
 				out.append(buffer, 0, bytes);
 		} while (bytes != -1);

 		return out.toString();
 	}

 	/**
 	 * Get the filesystem representation of a given resource. Does not try to resolve the resource.
 	 *
 	 * @param resource
 	 *            resource to convert. Either a {@link File} or an {@link IResource}
 	 * @return file or folder in the local file system
 	 */
 	public static File toFile(Object resource) {
 		if (resource instanceof File)
 			return (File) resource;

 		if (resource instanceof IResource) {
 			// on some projects getRawLocation() returns null
 			if (((IResource) resource).getRawLocation() != null)
 				return ((IResource) resource).getRawLocation().toFile();

 			return ((IResource) resource).getLocation().toFile();
 		}

 		return null;
 	}

 	/**
 	 * Creates a folder in the workspace if it does not exists already. Also creates any parent folder needed. Requires the project the folder resides to to
 	 * exist already.
 	 *
 	 * @param folder
 	 *            folder to be created
 	 * @throws CoreException
 	 *             when folder could not be created
 	 */
 	public static void createFolder(IContainer folder) throws CoreException {
 		if (!folder.exists()) {
 			if (!folder.getParent().exists())
 				createFolder(folder.getParent());

 			if (folder instanceof IFolder)
 				((IFolder) folder).create(true, true, new NullProgressMonitor());
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2014 Christian Pontesegger 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:
	* Christian Pontesegger - initial API and implementation
	*******************************************************************************/
	package org.eclipse.ease.tools;

	import java.io.BufferedInputStream;
	import java.io.File;
	import java.io.FileInputStream;
	import java.io.IOException;
	import java.io.InputStream;
	import java.io.InputStreamReader;
	import java.io.Reader;
	import java.net.MalformedURLException;
	import java.net.URI;
	import java.net.URISyntaxException;
	import java.net.URL;
	import java.util.regex.Matcher;
	import java.util.regex.Pattern;

	import org.eclipse.core.resources.IContainer;
	import org.eclipse.core.resources.IFile;
	import org.eclipse.core.resources.IFolder;
	import org.eclipse.core.resources.IProject;
	import org.eclipse.core.resources.IResource;
	import org.eclipse.core.resources.IWorkspaceRoot;
	import org.eclipse.core.resources.ResourcesPlugin;
	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.IPath;
	import org.eclipse.core.runtime.NullProgressMonitor;
	import org.eclipse.core.runtime.Path;
	import org.eclipse.ease.Activator;
	import org.eclipse.ease.Logger;
	import org.eclipse.ease.urlhandler.WorkspaceURLConnection;

	public final class ResourceTools {

	/**
	* InputStream delegating all tasks to a base stream. The only method not forwarded is close().
	*/
	public static class NonClosingInputStream extends InputStream {

	private final InputStream fBaseStream;

	public NonClosingInputStream(InputStream baseStream) {
	fBaseStream = baseStream;
	}

	@Override
	public int read() throws IOException {
	return fBaseStream.read();
	}

	@Override
	public int available() throws IOException {
	return fBaseStream.available();
	}

	@Override
	public long skip(long n) throws IOException {
	return fBaseStream.skip(n);
	}

	@Override
	public boolean markSupported() {
	return fBaseStream.markSupported();
	}

	@Override
	public synchronized void mark(int readlimit) {
	fBaseStream.mark(readlimit);
	}

	@Override
	public synchronized void reset() throws IOException {
	fBaseStream.reset();
	}

	@Override
	public int read(byte[] b, int off, int len) throws IOException {
	return fBaseStream.read(b, off, len);
	}

	@Override
	public int read(byte[] b) throws IOException {
	return fBaseStream.read(b);
	}
	}

	private static final String PROJECT_SCHEME = "project";
	private static final String PROJECT_PREFIX = PROJECT_SCHEME + "://";

	private static final String WORKSPACE_SCHEME = "workspace";
	private static final String WORKSPACE_PREFIX = WORKSPACE_SCHEME + "://";

	private static final String FILE_SCHEME = "file";
	private static final String FILE_PREFIX = FILE_SCHEME + "://";

	private static final String SCRIPT_SCHEME = "script";

	private static final Pattern WINDOWS_LOCAL_FILE_PATTERN = Pattern.compile("(?:file:///?)?([A-Z]:[/\\\\].*)");
	private static final Pattern WINDOWS_NETWORK_FILE_PATTERN = Pattern.compile("(?:file\\:)?((?://\|\\\\\\\\)[^:/][^:]*)");

	/** Virtual file indicating a file system root on windows. Needed as windows does not have a real root file object. */
	public static final Object VIRTUAL_WINDOWS_ROOT = new File("/");

	/**
	* @deprecated
	*/
	@Deprecated
	private ResourceTools() {
	}

	/**
	* Resolve to an existing File/IResource/URI/URL. For relative locations the parent object location is taken into account.
	*
	* @param location
	* location to resolve
	* @param parent
	* parent location to resolve from (needs to be absolute)
	* @return resource or <code>null</code>
	*/
	public static Object resolve(Object location, Object parent) {
	if ((location instanceof File) \|\| (location instanceof IResource) \|\| (location instanceof URI) \|\| (location instanceof URL))
	return location;

	if ((location == null) \|\| (location.toString().trim().isEmpty())) {
	final Object resolvedParent = resolve(parent);
	if (resolvedParent instanceof IFile)
	return ((IFile) resolvedParent).getParent();

	if ((resolvedParent instanceof File) && (((File) resolvedParent).isFile()))
	return ((File) resolvedParent).getParentFile();

	return resolvedParent;
	}

	final String locationStr = location.toString();
	if (isAbsolute(locationStr))
	return resolve(location);

	// simple checks done, now we need the parent
	parent = resolve(parent);
	if (!exists(parent))
	return null;

	if (parent instanceof IResource) {
	// resolve within workspace

	if (locationStr.startsWith(PROJECT_PREFIX)) {
	// "project://..." location
	final String targetPath = WORKSPACE_PREFIX + ((IResource) parent).getProject().getName() + "/" + locationStr.substring(PROJECT_PREFIX.length());
	return resolve(targetPath);
	}

	// pure relative location
	final IPath parentPath = (parent instanceof IFile) ? ((IResource) parent).getParent().getFullPath() : ((IResource) parent).getFullPath();
	final IPath locationPath = new Path(locationStr);

	IPath targetPath;
	if (locationPath.segmentCount() > parentPath.segmentCount()) {
	// check for special case when relative path steps out of workspace hierarchy
	targetPath = appendPath(parentPath, locationPath);
	} else
	targetPath = parentPath.append(locationPath);

	if (targetPath != null) {
	final Object resolvedTarget = resolve(WORKSPACE_PREFIX + targetPath.makeRelative().toPortableString());
	if (resolvedTarget != null)
	return resolvedTarget;
	}

	// could not resolve within the workspace, try within the file system
	parent = toFile(parent);
	}

	if (parent instanceof File) {
	// resolve within file system
	final Path parentPath = new Path(
	(((File) parent).isFile()) ? ((File) parent).getParentFile().getAbsolutePath() : ((File) parent).getAbsolutePath());

	final IPath targetPath = parentPath.append(new Path(locationStr));
	return targetPath.toFile();
	}

	if (parent instanceof URL) {
	try {
	parent = ((URL) parent).toURI();
	} catch (final URISyntaxException e) {
	// TODO handle this exception (but for now, at least know it happened)
	throw new RuntimeException(e);
	}
	}

	if (parent instanceof URI) {
	return ((URI) parent).resolve(locationStr);
	}

	return null;
	}

	/**
	* Manually add segment by segment to a path to make sure we do not step back outside of the given parent path. Tries to detect cases like this one:
	* '/some/path/../../..' which do not get resolved correctly by path.append().
	*
	* @param parentPath
	* parent path
	* @param locationPath
	* relative path to append
	* @return appended path or <code>null</code> in case we leave the context
	*/
	private static IPath appendPath(IPath parentPath, IPath locationPath) {
	if (locationPath.segmentCount() > 0) {
	final IPath newParent = parentPath.append(locationPath.segment(0));
	if (parentPath.equals(newParent))
	return null;

	return appendPath(newParent, locationPath.removeFirstSegments(1));

	} else
	return parentPath;
	}

	/**
	* Check whether a resource exists. Works only for IResource, File, URI, URL objects. Does not try to resolve the given location.
	*
	* @param resource
	* resource to query for
	* @return <code>true</code> if resource exists or is of type URI or URL
	*/
	public static boolean exists(Object resource) {
	if (resource instanceof IResource)
	return ((IResource) resource).exists();

	if (resource instanceof File)
	return ((File) resource).exists();

	if ((resource instanceof URI) \|\| (resource instanceof URL))
	return true;

	return false;
	}

	/**
	* Check if a resource exists and is of type file. Does not resolve the resource.
	*
	* @param resource
	* {@link File} or {@link IResource} object
	* @return <code>true</code> when resource is a file
	*/
	public static boolean isFile(Object resource) {
	if (exists(resource)) {
	if (resource instanceof IFile)
	return true;

	if ((resource instanceof File) && (((File) resource).isFile()))
	return true;
	}

	return false;
	}

	/**
	* Check if a resource exists and is of type folder. For the eclipse workspace this check is also true for the workspace root and project locations. Does
	* not resolve the resource.
	*
	* @param resource
	* {@link File} or {@link IResource} object
	* @return <code>true</code> when resource is a folder
	*/
	public static boolean isFolder(Object resource) {
	if (exists(resource)) {
	if (resource instanceof IContainer)
	return true;

	if ((resource instanceof File) && (((File) resource).isDirectory()))
	return true;
	}

	return false;
	}

	/**
	* Resolve to an existing File/IResource/URI/URL.
	*
	* @param location
	* location to resolve
	* @return resource or <code>null</code>
	*/
	public static Object resolve(Object location) {
	if ((location instanceof File) \|\| (location instanceof IResource) \|\| (location instanceof URI) \|\| (location instanceof URL))
	return location;

	if ((location == null) \|\| (location.toString().trim().isEmpty()))
	return null;

	final String locationStr = location.toString();
	if (isAbsolute(locationStr)) {
	if (locationStr.startsWith(WORKSPACE_PREFIX)) {
	if (WORKSPACE_PREFIX.equals(locationStr))
	return getWorkspace();

	// workspace file
	final IPath path = new Path(locationStr.substring(WORKSPACE_PREFIX.length()));

	if (path.isEmpty())
	// user stepped back into workspace root
	return getWorkspace();

	final IProject project = getWorkspace().getProject(path.segment(0));
	if (project != null) {
	if (path.segmentCount() == 1)
	return project;

	final IFolder folder = project.getFolder(path.removeFirstSegments(1));
	if (folder.exists())
	return folder;

	return project.getFile(path.removeFirstSegments(1));
	}

	} else if (locationStr.startsWith(FILE_PREFIX)) {
	if (isWindows()) {
	Matcher matcher = WINDOWS_LOCAL_FILE_PATTERN.matcher(locationStr);
	if (matcher.matches())
	return new File(matcher.group(1));

	matcher = WINDOWS_NETWORK_FILE_PATTERN.matcher(locationStr);
	if (matcher.matches())
	return new File(matcher.group(1));

	else if (("file:///".equals(locationStr)) \|\| ("file://".equals(locationStr)))
	return VIRTUAL_WINDOWS_ROOT;

	// giving up
	return null;

	} else {
	if (locationStr.startsWith("file:///"))
	return new File(locationStr.substring(7));

	else if (locationStr.startsWith("file://"))
	return new File(locationStr.substring(6));

	else
	return new File(locationStr);
	}

	} else if (locationStr.startsWith(SCRIPT_SCHEME)) {
	// script scheme needs to resolve to URLs to be usable
	try {
	return new URL(locationStr);
	} catch (final MalformedURLException e1) {
	// TODO handle this exception (but for now, at least know it happened)
	throw new RuntimeException(e1);
	}

	} else if ((locationStr.contains(":/")) && (locationStr.indexOf(":/") != 1)) {
	// the check: (locationStr.indexOf(":/") != 1) eliminates windows file 'URIs' like C:/mydata/...
	// simple check for URI schemes
	try {
	return createURI(locationStr);

	} catch (final MalformedURLException e) {
	// could be thrown for unknown protocols like svn://

	// fallback, no more escaping of spaces
	return URI.create(locationStr);

	} catch (final URISyntaxException e) {
	// TODO handle this exception (but for now, at least know it happened)
	throw new RuntimeException(e);
	}

	} else {
	// quite likely an absolute path into the file system
	return new File(locationStr);
	}
	}

	return null;
	}

	public static boolean isWindows() {
	return System.getProperty("os.name").toLowerCase().startsWith("windows");
	}

	/**
	* Correctly escapes spaces in URIs.
	*
	* @param address
	* address to create URI for
	* @return URI
	* @throws MalformedURLException
	* @throws URISyntaxException
	*/
	public static URI createURI(String address) throws MalformedURLException, URISyntaxException {
	final URL url = new URL(address);
	return new URI(url.getProtocol(), url.getUserInfo(), url.getHost(), url.getPort(), url.getPath(), url.getQuery(), url.getRef());
	}

	/**
	* Get the workspace root.
	*
	* @return workspace root
	*/
	private static IWorkspaceRoot getWorkspace() {
	return ResourcesPlugin.getWorkspace().getRoot();
	}

	/**
	* Verifies if a location is provided in absolute form.
	*
	* @param location
	* location string
	* @return <code>true</code> for absolute locations
	*/
	public static boolean isAbsolute(String location) {
	if (location.startsWith(PROJECT_PREFIX))
	return false;

	// simple check for URI style
	if (location.contains(":/"))
	return true;

	// check for windows files
	if (WINDOWS_LOCAL_FILE_PATTERN.matcher(location).matches())
	return true;

	if (WINDOWS_NETWORK_FILE_PATTERN.matcher(location).matches())
	return true;

	return new Path(location).isAbsolute();
	}

	/**
	* Provides the project relative URI for a given workspace resource. The provided location will be of type 'project://...'.
	*
	* @param resource
	* resource to get relative URI for.
	* @return project relative location
	*/
	public static String toProjectRelativeLocation(final IResource resource) {
	return PROJECT_SCHEME + "://" + resource.getProjectRelativePath().toPortableString();
	}

	/**
	* Resolve a given location to an absolute location URI. When <i>location</i> is not a string, we create an absolute string representation of the given
	* location.
	*
	* @param location
	* (relative) location
	* @param parent
	* parent object to resolve from
	* @return resolved location string or <code>null</code>
	*/
	public static String toAbsoluteLocation(final Object location, final Object parent) {

	// try to resolve file
	final Object file = resolve(location, parent);
	if (file instanceof IResource)
	return WorkspaceURLConnection.SCHEME + ":/" + ((IResource) file).getFullPath().toPortableString();

	else if (file instanceof File) {
	if (isWindows()) {
	// change backslashes to forward slashes
	final String filePath = ((File) file).toString().replaceAll("\\\\", "/");
	if (filePath.startsWith("//"))
	return "file://" + filePath.substring(2);

	return "file:///" + filePath;

	} else
	return "file://" + ((File) file).toString();
	}

	else if (file != null)
	return file.toString();

	// nothing to resolve, return null
	return null;
	}

	/**
	* Create a relative path from one resource to another.
	*
	* @param resource
	* resource to create a relative path for
	* @param parent
	* resource to create relative path from
	* @return relative path for <i>resource</i>
	*/
	public static String toRelativeLocation(Object resource, Object parent) {
	resource = resolve(resource);
	if (resource == null)
	return null;

	parent = resolve(parent);
	if (parent == null)
	return null;

	if (isFile(parent)) {
	if (parent instanceof IFile)
	parent = ((IFile) parent).getParent();
	else if (parent instanceof File)
	parent = ((File) parent).getParentFile();
	}

	IPath parentPath;
	IPath resourcePath;

	if ((resource instanceof IResource) && (parent instanceof IResource)) {
	// within workspace
	parentPath = ((IResource) parent).getFullPath();
	resourcePath = ((IResource) resource).getFullPath();

	} else {
	// within file system
	resource = toFile(resource);
	parent = toFile(parent);

	try {
	parentPath = new Path(((File) parent).getCanonicalPath());
	resourcePath = new Path(((File) resource).getCanonicalPath());
	if (!parentPath.getDevice().equals(resourcePath.getDevice()))
	// different devices, no relative path possible
	return null;
	} catch (final IOException e) {
	// could not get canonical path, giving up
	return null;
	}
	}

	// concatenate paths
	final int matchingSegments = parentPath.matchingFirstSegments(resourcePath);
	parentPath = parentPath.removeFirstSegments(matchingSegments);
	resourcePath = resourcePath.removeFirstSegments(matchingSegments);

	for (int index = 0; index < parentPath.segmentCount(); index++)
	resourcePath = new Path("..").append(resourcePath);

	return resourcePath.toPortableString();
	}

	/**
	* Get the content of a resource location as {@link InputStream}.
	*
	* @param location
	* location to read from
	* @return {@link InputStream} or <code>null</code>
	*/
	public static InputStream getInputStream(final Object location) {
	if (location instanceof InputStream)
	return (InputStream) location;

	try {
	final Object resource = resolve(location);
	if (resource instanceof IFile)
	return ((IFile) resource).getContents();

	if (resource instanceof File)
	return new FileInputStream((File) resource);

	if (resource instanceof URI)
	return ((URI) resource).toURL().openStream();

	// last resort: try to create a URL directly
	if (location != null)
	return new URL(location.toString()).openStream();

	} catch (final Exception e) {
	// cannot open stream
	Logger.error(Activator.PLUGIN_ID, "Cannot open stream for \"" + location + "\"", e);
	}

	return null;
	}

	/**
	* Reads from a resource into a string. Does not throw any exceptions, instead returns <code>null</code> in case of errors and logs the error to the system
	* logger.
	*
	* @param location
	* location to look up
	* @return content or <code>null</code> in case of error
	*/
	public static String toString(final Object location) {
	try {
	final InputStream inputStream = new BufferedInputStream(getInputStream(location));
	return StringTools.toString(inputStream);
	} catch (final IOException e) {
	Logger.error(Activator.PLUGIN_ID, "Cannot read from resource \"" + location + "\"", e);
	}

	return null;
	}

	/**
	* Convert an input stream to a string.
	*
	* @param stream
	* input string to read from
	* @return string containing stream data
	* @throws IOException
	* thrown on problems with input stream
	*/
	public static String toString(final InputStream stream) throws IOException {
	if (stream == null)
	return null;

	return toString(new InputStreamReader(stream));
	}

	/**
	* Read characters from a {@link Reader} and return its string representation. Can be used to convert an {@link InputStream} to a string.
	*
	* @param reader
	* reader to read from
	* @return string content of reader
	* @throws IOException
	* when reader is not accessible
	*/
	public static String toString(final Reader reader) throws IOException {
	if (reader == null)
	return null;

	final StringBuffer out = new StringBuffer();

	final char[] buffer = new char[1024];
	int bytes = 0;
	do {
	bytes = reader.read(buffer);
	if (bytes > 0)
	out.append(buffer, 0, bytes);
	} while (bytes != -1);

	return out.toString();
	}

	/**
	* Get the filesystem representation of a given resource. Does not try to resolve the resource.
	*
	* @param resource
	* resource to convert. Either a {@link File} or an {@link IResource}
	* @return file or folder in the local file system
	*/
	public static File toFile(Object resource) {
	if (resource instanceof File)
	return (File) resource;

	if (resource instanceof IResource) {
	// on some projects getRawLocation() returns null
	if (((IResource) resource).getRawLocation() != null)
	return ((IResource) resource).getRawLocation().toFile();

	return ((IResource) resource).getLocation().toFile();
	}

	return null;
	}

	/**
	* Creates a folder in the workspace if it does not exists already. Also creates any parent folder needed. Requires the project the folder resides to to
	* exist already.
	*
	* @param folder
	* folder to be created
	* @throws CoreException
	* when folder could not be created
	*/
	public static void createFolder(IContainer folder) throws CoreException {
	if (!folder.exists()) {
	if (!folder.getParent().exists())
	createFolder(folder.getParent());

	if (folder instanceof IFolder)
	((IFolder) folder).create(true, true, new NullProgressMonitor());
	}
	}
	}