stringutils.java

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	 *            the input Object (e.g. "myString")
	 * @return the quoted String (e.g. "'myString'"), or the
	 *         input object as-is if not a String
	 */
	public static Object quoteIfString(Object obj) {
		return (obj instanceof String ? quote((String) obj) : obj);
	}

	/**
	 * Unqualify a string qualified by a '.' dot character.
	 * For example, "this.name.is.qualified", returns
	 * "qualified".
	 * 
	 * @param qualifiedName
	 *            the qualified name
	 */
	public static String unqualify(String qualifiedName) {
		return unqualify(qualifiedName, '.');
	}

	/**
	 * Unqualify a string qualified by a separator
	 * character. For example, "this:name:is:qualified"
	 * returns "qualified" if using a ':' separator.
	 * 
	 * @param qualifiedName
	 *            the qualified name
	 * @param separator
	 *            the separator
	 */
	public static String unqualify(String qualifiedName, char separator) {
		return qualifiedName
				.substring(qualifiedName.lastIndexOf(separator) + 1);
	}

	/**
	 * Capitalize a <code>String</code>, changing the
	 * first letter to upper case as per
	 * {@link Character#toUpperCase(char)}. No other
	 * letters are changed.
	 * 
	 * @param str
	 *            the String to capitalize, may be
	 *            <code>null</code>
	 * @return the capitalized String, <code>null</code>
	 *         if null
	 */
	public static String capitalize(String str) {
		return changeFirstCharacterCase(str, true);
	}

	/**
	 * Uncapitalize a <code>String</code>, changing the
	 * first letter to lower case as per
	 * {@link Character#toLowerCase(char)}. No other
	 * letters are changed.
	 * 
	 * @param str
	 *            the String to uncapitalize, may be
	 *            <code>null</code>
	 * @return the uncapitalized String, <code>null</code>
	 *         if null
	 */
	public static String uncapitalize(String str) {
		return changeFirstCharacterCase(str, false);
	}

	private static String changeFirstCharacterCase(String str,
			boolean capitalize) {
		if (str == null || str.length() == 0) {
			return str;
		}
		StringBuffer buf = new StringBuffer(str.length());
		if (capitalize) {
			buf.append(Character.toUpperCase(str.charAt(0)));
		} else {
			buf.append(Character.toLowerCase(str.charAt(0)));
		}
		buf.append(str.substring(1));
		return buf.toString();
	}

	/**
	 * Extract the filename from the given path, e.g.
	 * "mypath/myfile.txt" -> "myfile.txt".
	 * 
	 * @param path
	 *            the file path (may be <code>null</code>)
	 * @return the extracted filename, or <code>null</code>
	 *         if none
	 */
	public static String getFilename(String path) {
		if (path == null) {
			return null;
		}
		int separatorIndex = path.lastIndexOf(FOLDER_SEPARATOR);
		return (separatorIndex != -1 ? path.substring(separatorIndex + 1)
				: path);
	}

	/**
	 * Extract the filename extension from the given path,
	 * e.g. "mypath/myfile.txt" -> "txt".
	 * 
	 * @param path
	 *            the file path (may be <code>null</code>)
	 * @return the extracted filename extension, or
	 *         <code>null</code> if none
	 */
	public static String getFilenameExtension(String path) {
		if (path == null) {
			return null;
		}
		int sepIndex = path.lastIndexOf(EXTENSION_SEPARATOR);
		return (sepIndex != -1 ? path.substring(sepIndex + 1) : null);
	}

	/**
	 * Strip the filename extension from the given path,
	 * e.g. "mypath/myfile.txt" -> "mypath/myfile".
	 * 
	 * @param path
	 *            the file path (may be <code>null</code>)
	 * @return the path with stripped filename extension, or
	 *         <code>null</code> if none
	 */
	public static String stripFilenameExtension(String path) {
		if (path == null) {
			return null;
		}
		int sepIndex = path.lastIndexOf(EXTENSION_SEPARATOR);
		return (sepIndex != -1 ? path.substring(0, sepIndex) : path);
	}

	/**
	 * Apply the given relative path to the given path,
	 * assuming standard Java folder separation (i.e. "/"
	 * separators);
	 * 
	 * @param path
	 *            the path to start from (usually a full
	 *            file path)
	 * @param relativePath
	 *            the relative path to apply (relative to
	 *            the full file path above)
	 * @return the full file path that results from applying
	 *         the relative path
	 */
	public static String applyRelativePath(String path, String relativePath) {
		int separatorIndex = path.lastIndexOf(FOLDER_SEPARATOR);
		if (separatorIndex != -1) {
			String newPath = path.substring(0, separatorIndex);
			if (!relativePath.startsWith(FOLDER_SEPARATOR)) {
				newPath += FOLDER_SEPARATOR;
			}
			return newPath + relativePath;
		} else {
			return relativePath;
		}
	}

	/**
	 * Normalize the path by suppressing sequences like
	 * "path/.." and inner simple dots.
	 * <p>
	 * The result is convenient for path comparison. For
	 * other uses, notice that Windows separators ("\") are
	 * replaced by simple slashes.
	 * 
	 * @param path
	 *            the original path
	 * @return the normalized path
	 */
	public static String cleanPath(String path) {
		String pathToUse = replace(path, WINDOWS_FOLDER_SEPARATOR,
				FOLDER_SEPARATOR);

		// Strip prefix from path to analyze, to not treat
		// it as part of the
		// first path element. This is necessary to
		// correctly parse paths like
		// "file:core/../core/io/Resource.class", where the
		// ".." should just
		// strip the first "core" directory while keeping
		// the "file:" prefix.
		int prefixIndex = pathToUse.indexOf(":");
		String prefix = "";
		if (prefixIndex != -1) {
			prefix = pathToUse.substring(0, prefixIndex + 1);
			pathToUse = pathToUse.substring(prefixIndex + 1);
		}

		String[] pathArray = delimitedListToStringArray(pathToUse,
				FOLDER_SEPARATOR);
		List pathElements = new LinkedList();
		int tops = 0;

		for (int i = pathArray.length - 1; i >= 0; i--) {
			if (CURRENT_PATH.equals(pathArray[i])) {
				// Points to current directory - drop it.
			} else if (TOP_PATH.equals(pathArray[i])) {
				// Registering top path found.
				tops++;
			} else {
				if (tops > 0) {
					// Merging path element with
					// corresponding to top path.
					tops--;
				} else {
					// Normal path element found.
					pathElements.add(0, pathArray[i]);
				}
			}
		}

		// Remaining top paths need to be retained.
		for (int i = 0; i < tops; i++) {
			pathElements.add(0, TOP_PATH);
		}

		return prefix
				+ collectionToDelimitedString(pathElements, FOLDER_SEPARATOR);
	}

	/**
	 * Compare two paths after normalization of them.
	 * 
	 * @param path1
	 *            First path for comparizon
	 * @param path2
	 *            Second path for comparizon
	 * @return whether the two paths are equivalent after
	 *         normalization
	 */
	public static boolean pathEquals(String path1, String path2) {
		return cleanPath(path1).equals(cleanPath(path2));
	}

	/**
	 * Parse the given locale string into a
	 * <code>java.util.Locale</code>. This is the inverse
	 * operation of Locale's <code>toString</code>.
	 * 
	 * @param localeString
	 *            the locale string, following
	 *            <code>java.util.Locale</code>'s
	 *            toString format ("en", "en_UK", etc). Also
	 *            accepts spaces as separators, as
	 *            alternative to underscores.
	 * @return a corresponding Locale instance
	 */
	public static Locale parseLocaleString(String localeString) {
		String[] parts = tokenizeToStringArray(localeString, "_ ", false, false);
		String language = (parts.length > 0 ? parts[0] : "");
		String country = (parts.length > 1 ? parts[1] : "");
		String variant = (parts.length > 2 ? parts[2] : "");
		return (language.length() > 0 ? new Locale(language, country, variant)
				: null);
	}

	// ---------------------------------------------------------------------
	// Convenience methods for working with String arrays
	// ---------------------------------------------------------------------

	/**
	 * Append the given String to the given String array,
	 * returning a new array consisting of the input array
	 * contents plus the given String.
	 * 
	 * @param array
	 *            the array to append to (can be
	 *            <code>null</code>)
	 * @param str
	 *            the String to append
	 * @return the new array (never <code>null</code>)
	 */
	public static String[] addStringToArray(String[] array, String str) {
		if (array == null || array.length < 0) {
			return new String[] { str };
		}
		String[] newArr = new String[array.length + 1];
		System.arraycopy(array, 0, newArr, 0, array.length);
		newArr[array.length] = str;
		return newArr;
	}

	/**
	 * Turn given source String array into sorted array.
	 * 
	 * @param array
	 *            the source array
	 * @return the sorted array (never <code>null</code>)
	 */
	public static String[] sortStringArray(String[] array) {
		if (array == null || array.length < 0) {
			return new String[0];
		}
		Arrays.sort(array);
		return array;
	}

	/**
	 * Copy the given Collection into a String array. The
	 * Collection must contain String elements only.
	 * 
	 * @param collection
	 *            the Collection to copy
	 * @return the String array (<code>null</code> if the
	 *         Collection was <code>null</code> as well)
	 */
	public static String[] toStringArray(Collection collection) {
		if (collection == null) {
			return null;
		}
		return (String[]) collection.toArray(new String[collection.size()]);
	}

	/**
	 * Remove duplicate Strings from the given array. Also
	 * sorts the array, as it uses a TreeSet.
	 * 
	 * @param array
	 *            the String array
	 * @return an array without duplicates, in natural sort
	 *         order
	 */
	public static String[] removeDuplicateStrings(String[] array) {
		if (array == null || array.length < 0) {
			return array;
		}
		Set set = new TreeSet();
		for (int i = 0; i < array.length; i++) {
			set.add(array[i]);
		}
		return toStringArray(set);
	}

	/**
	 * Split a String at the first occurrence of the
	 * delimiter. Does not include the delimiter in the
	 * result.
	 * 
	 * @param toSplit
	 *            the string to split
	 * @param delimiter
	 *            to split the string up with
	 * @return a two element array with index 0 being before
	 *         the delimiter, and index 1 being after the