Metacat

import java.io.IOException;

	 * to give you the actual directory.  Here are the steps taken to discover

	 * the directory:

	 * -- 1) Look for a saved backup location file in the user home dir - Is there a file named 

	 *       <user_home>/.metacat/backup-location for the user that started tomcat? if so, does 

	 *       it contain a single line which is a readable directory?  This directory was the backup 

	 *       directory used during a previous install.  Return that directory.

	 * -- 2) Look for an existing hidden (.metacat) directory in a default system directory.  Get 

	 *       the default base directory for the OS.  (See application.windowsBackupBaseDir and 

	 *       application.linuxBackupBaseDir in metacat.properties.)  If a directory called 

	 *       <base_dir>/metacat/.metacat exists, return <base_dir>/metacat.

	 * -- 3) Look for an existing hidden (.metacat) directory in the user directory. If a directory 

	 *       called <user_dir>/.metacat exists for the user that started tomcat, return <user_dir>.

	 * -- 4) Is the <base_dir> writable by the user that started tomcat?  If so, return <base_dir>

	 * -- 5) Does the <user_home> exist?  If so, return <user_home>

	 * -- 6) Otherwise, return null

	 *    

	public static String discoverExternalBaseDir() throws PropertyNotFoundException {

		String userHomeDir = getUserHomeDir();

		String defaultBaseDir = "";

		try {

			// Check if there is a file at <user_home>/.metacat/backup-location.  If so, it

			// should contain one line that is a file that points to a writable directory. 

			// If that is true, use that value as the external dir.

			String storedBackupFileLoc = getUserHomeDir() + FileUtil.getFS() + ".metacat"

					+ FileUtil.getFS() + "backup-location";

			if (FileUtil.getFileStatus(storedBackupFileLoc) >= FileUtil.EXISTS_READABLE) {

				String storedBackupDirLoc = FileUtil.readFileToString(storedBackupFileLoc);

				if (FileUtil.isDirectory(storedBackupDirLoc)

						&& FileUtil.getFileStatus(storedBackupDirLoc) > FileUtil.EXISTS_READABLE) {

					return storedBackupDirLoc;

				}

			}

		} catch (IOException ioe) {

			logMetacat.warn("Could not read stored backup location: " + ioe.getMessage());

		}

		// Set the default location using the os

			defaultBaseDir = PropertyService.getProperty("application.windowsBackupBaseDir");

		} else {

			defaultBaseDir = PropertyService.getProperty("application.linuxBackupBaseDir");

		String defaultBackupDir = defaultBaseDir + FileUtil.getFS() + "metacat";

		String defaultBackupHiddenDir = defaultBackupDir + FileUtil.getFS() + ".metacat";

		String userHomeBackupHiddenDir = userHomeDir + FileUtil.getFS() + ".metacat";

		// If <base_dir>/metacat/.metacat exists, return <base_dir>

		if ((FileUtil.getFileStatus(defaultBackupHiddenDir) >= FileUtil.EXISTS_READ_WRITABLE)) {

			return defaultBaseDir;

		}

		// Otherwise if <user_dir>/.metacat exists, return <user_dir>

		if ((FileUtil.getFileStatus(userHomeBackupHiddenDir) >= FileUtil.EXISTS_READ_WRITABLE)) {

			return userHomeDir;

		}

		// Otherwise if <base_dir>/metacat exists, return <base_dir>

		if ((FileUtil.getFileStatus(defaultBaseDir) >= FileUtil.EXISTS_READ_WRITABLE)) {

			return defaultBaseDir;

		}

		// Otherwise if <user_dir> exists, return <user_dir>

		if ((FileUtil.getFileStatus(userHomeDir) >= FileUtil.EXISTS_READ_WRITABLE)) {

			return userHomeDir;

		}

		// Otherwise, return userHomeDir

		return null;

	/**

	 * Store the location of the backup file location into a file at 

	 * <user_home>/.metacat/backup-location

	 * 

	 * @param externalDir the backup file location.

	 */

	public static void storeExternalDirLocation(String externalDir) {

		if (getUserHomeDir() != null) {

			String storedBackupDirLoc = getUserHomeDir() + FileUtil.getFS() + ".metacat"

					+ FileUtil.getFS() + "backup-location";

			try {

				FileUtil.writeFile(storedBackupDirLoc, externalDir);

			} catch (IOException ioe) {

				logMetacat.error("I/O error while trying to write stored backup directory: "

								+ storedBackupDirLoc + " : " + ioe.getMessage());

			}

		} else {

			logMetacat.warn("Could not write out stored backup directory." 

					+ " User directory does not exist");

		}

	}

	/**

	 * Get the current user's home directory

	 * 

	 * @return a string holding the home directory

	 */

	public static String getUserHomeDir() {

		return System.getProperty("user.home");

	}