package org.audit4j.core.schedule.util; import java.util.ArrayList; import java.util.Collection; import java.util.Collections; import java.util.Enumeration; import java.util.Iterator; import java.util.LinkedList; import java.util.List; import java.util.Locale; import java.util.Properties; import java.util.Set; import java.util.StringTokenizer; import java.util.TimeZone; import java.util.TreeSet; public class StringUtils { private static final String FOLDER_SEPARATOR = "/"; private static final String WINDOWS_FOLDER_SEPARATOR = "\\"; private static final String TOP_PATH = ".."; private static final String CURRENT_PATH = "."; private static final char EXTENSION_SEPARATOR = '.'; /** * private constructor to avoid instantiation of this class */ private StringUtils(){ } // --------------------------------------------------------------------- // General convenience methods for working with Strings // --------------------------------------------------------------------- /** * Check whether the given String is empty. * <p> * This method accepts any Object as an argument, comparing it to * {@code null} and the empty String. As a consequence, this method will * never return {@code true} for a non-null non-String object. * <p> * The Object signature is useful for general attribute handling code that * commonly deals with Strings but generally has to iterate over Objects * since attributes may e.g. be primitive value objects as well. * * @param str * the candidate String * @since 3.2.1 */ public static boolean isEmpty(Object str) { return str == null || "".equals(str); } /** * Check that the given CharSequence is neither {@code null} nor of length * 0. Note: Will return {@code true} for a CharSequence that purely consists * of whitespace. * <p> * * <pre class="code"> * StringUtils.hasLength(null) = false * StringUtils.hasLength("") = false * StringUtils.hasLength(" ") = true * StringUtils.hasLength("Hello") = true * </pre> * * @param str * the CharSequence to check (may be {@code null}) * @return {@code true} if the CharSequence is not null and has length * @see #hasText(String) */ public static boolean hasLength(CharSequence str) { return str != null && str.length() > 0; } /** * Check that the given String is neither {@code null} nor of length 0. * Note: Will return {@code true} for a String that purely consists of * whitespace. * * @param str * the String to check (may be {@code null}) * @return {@code true} if the String is not null and has length * @see #hasLength(CharSequence) */ public static boolean hasLength(String str) { return hasLength((CharSequence) str); } /** * Check whether the given CharSequence has actual text. More specifically, * returns {@code true} if the string not {@code null}, its length is * greater than 0, and it contains at least one non-whitespace character. * <p> * * <pre class="code"> * StringUtils.hasText(null) = false * StringUtils.hasText("") = false * StringUtils.hasText(" ") = false * StringUtils.hasText("12345") = true * StringUtils.hasText(" 12345 ") = true * </pre> * * @param str * the CharSequence to check (may be {@code null}) * @return {@code true} if the CharSequence is not {@code null}, its length * is greater than 0, and it does not contain whitespace only * @see Character#isWhitespace */ public static boolean hasText(CharSequence str) { if (!hasLength(str)) { return false; } int strLen = str.length(); for (int i = 0; i < strLen; i++) { if (!Character.isWhitespace(str.charAt(i))) { return true; } } return false; } /** * Check whether the given String has actual text. More specifically, * returns {@code true} if the string not {@code null}, its length is * greater than 0, and it contains at least one non-whitespace character. * * @param str * the String to check (may be {@code null}) * @return {@code true} if the String is not {@code null}, its length is * greater than 0, and it does not contain whitespace only * @see #hasText(CharSequence) */ public static boolean hasText(String str) { return hasText((CharSequence) str); } /** * Check whether the given CharSequence contains any whitespace characters. * * @param str * the CharSequence to check (may be {@code null}) * @return {@code true} if the CharSequence is not empty and contains at * least 1 whitespace character * @see Character#isWhitespace */ public static boolean containsWhitespace(CharSequence str) { if (!hasLength(str)) { return false; } int strLen = str.length(); for (int i = 0; i < strLen; i++) { if (Character.isWhitespace(str.charAt(i))) { return true; } } return false; } /** * Check whether the given String contains any whitespace characters. * * @param str * the String to check (may be {@code null}) * @return {@code true} if the String is not empty and contains at least 1 * whitespace character * @see #containsWhitespace(CharSequence) */ public static boolean containsWhitespace(String str) { return containsWhitespace((CharSequence) str); } /** * Trim leading and trailing whitespace from the given String. * * @param str * the String to check * @return the trimmed String * @see java.lang.Character#isWhitespace */ public static String trimWhitespace(String str) { if (!hasLength(str)) { return str; } StringBuilder sb = new StringBuilder(str); while (sb.length() > 0 && Character.isWhitespace(sb.charAt(0))) { sb.deleteCharAt(0); } while (sb.length() > 0 && Character.isWhitespace(sb.charAt(sb.length() - 1))) { sb.deleteCharAt(sb.length() - 1); } return sb.toString(); } /** * Trim <i>all</i> whitespace from the given String: leading, trailing, and * in between characters. * * @param str * the String to check * @return the trimmed String * @see java.lang.Character#isWhitespace */ public static String trimAllWhitespace(String str) { if (!hasLength(str)) { return str; } int len = str.length(); StringBuilder sb = new StringBuilder(str.length()); for (int i = 0; i < len; i++) { char c = str.charAt(i); if (!Character.isWhitespace(c)) { sb.append(c); } } return sb.toString(); } /** * Trim leading whitespace from the given String. * * @param str * the String to check * @return the trimmed String * @see java.lang.Character#isWhitespace */ public static String trimLeadingWhitespace(String str) { if (!hasLength(str)) { return str; } StringBuilder sb = new StringBuilder(str); while (sb.length() > 0 && Character.isWhitespace(sb.charAt(0))) { sb.deleteCharAt(0); } return sb.toString(); } /** * Trim trailing whitespace from the given String. * * @param str * the String to check * @return the trimmed String * @see java.lang.Character#isWhitespace */ public static String trimTrailingWhitespace(String str) { if (!hasLength(str)) { return str; } StringBuilder sb = new StringBuilder(str); while (sb.length() > 0 && Character.isWhitespace(sb.charAt(sb.length() - 1))) { sb.deleteCharAt(sb.length() - 1); } return sb.toString(); } /** * Trim all occurrences of the supplied leading character from the given * String. * * @param str * the String to check * @param leadingCharacter * the leading character to be trimmed * @return the trimmed String */ public static String trimLeadingCharacter(String str, char leadingCharacter) { if (!hasLength(str)) { return str; } StringBuilder sb = new StringBuilder(str); while (sb.length() > 0 && sb.charAt(0) == leadingCharacter) { sb.deleteCharAt(0); } return sb.toString(); } /** * Trim all occurrences of the supplied trailing character from the given * String. * * @param str * the String to check * @param trailingCharacter * the trailing character to be trimmed * @return the trimmed String */ public static String trimTrailingCharacter(String str, char trailingCharacter) { if (!hasLength(str)) { return str; } StringBuilder sb = new StringBuilder(str); while (sb.length() > 0 && sb.charAt(sb.length() - 1) == trailingCharacter) { sb.deleteCharAt(sb.length() - 1); } return sb.toString(); } /** * Test if the given String starts with the specified prefix, ignoring * upper/lower case. * * @param str * the String to check * @param prefix * the prefix to look for * @see java.lang.String#startsWith */ public static boolean startsWithIgnoreCase(String str, String prefix) { if (str == null || prefix == null) { return false; } if (str.startsWith(prefix)) { return true; } if (str.length() < prefix.length()) { return false; } String lcStr = str.substring(0, prefix.length()).toLowerCase(); String lcPrefix = prefix.toLowerCase(); return lcStr.equals(lcPrefix); } /** * Test if the given String ends with the specified suffix, ignoring * upper/lower case. * * @param str * the String to check * @param suffix * the suffix to look for * @see java.lang.String#endsWith */ public static boolean endsWithIgnoreCase(String str, String suffix) { if (str == null || suffix == null) { return false; } if (str.endsWith(suffix)) { return true; } if (str.length() < suffix.length()) { return false; } String lcStr = str.substring(str.length() - suffix.length()).toLowerCase(); String lcSuffix = suffix.toLowerCase(); return lcStr.equals(lcSuffix); } /** * Test whether the given string matches the given substring at the given * index. * * @param str * the original string (or StringBuilder) * @param index * the index in the original string to start matching against * @param substring * the substring to match at the given index */ public static boolean substringMatch(CharSequence str, int index, CharSequence substring) { for (int j = 0; j < substring.length(); j++) { int i = index + j; if (i >= str.length() || str.charAt(i) != substring.charAt(j)) { return false; } } return true; } /** * Count the occurrences of the substring in string s. * * @param str * string to search in. Return 0 if this is null. * @param sub * string to search for. Return 0 if this is null. */ public static int countOccurrencesOf(String str, String sub) { if (str == null || sub == null || str.length() == 0 || sub.length() == 0) { return 0; } int count = 0; int pos = 0; int idx; while ((idx = str.indexOf(sub, pos)) != -1) { ++count; pos = idx + sub.length(); } return count; } /** * Replace all occurrences of a substring within a string with another * string. * * @param inString * String to examine * @param oldPattern * String to replace * @param newPattern * String to insert * @return a String with the replacements */ public static String replace(String inString, String oldPattern, String newPattern) { if (!hasLength(inString) || !hasLength(oldPattern) || newPattern == null) { return inString; } StringBuilder sb = new StringBuilder(); int pos = 0; // our position in the old string int index = inString.indexOf(oldPattern); // the index of an occurrence we've found, or -1 int patLen = oldPattern.length(); while (index >= 0) { sb.append(inString.substring(pos, index)); sb.append(newPattern); pos = index + patLen; index = inString.indexOf(oldPattern, pos); } sb.append(inString.substring(pos)); // remember to append any characters to the right of a match return sb.toString(); } /** * Delete all occurrences of the given substring. * * @param inString * the original String * @param pattern * the pattern to delete all occurrences of * @return the resulting String */ public static String delete(String inString, String pattern) { return replace(inString, pattern, ""); } /** * Delete any character in a given String. * * @param inString * the original String * @param charsToDelete * a set of characters to delete. E.g. "az\n" will delete 'a's, * 'z's and new lines. * @return the resulting String */ public static String deleteAny(String inString, String charsToDelete) { if (!hasLength(inString) || !hasLength(charsToDelete)) { return inString; } StringBuilder sb = new StringBuilder(); for (int i = 0; i < inString.length(); i++) { char c = inString.charAt(i); if (charsToDelete.indexOf(c) == -1) { sb.append(c); } } return sb.toString(); } // --------------------------------------------------------------------- // Convenience methods for working with formatted Strings // --------------------------------------------------------------------- /** * Quote the given String with single quotes. * * @param str * the input String (e.g. "myString") * @return the quoted String (e.g. "'myString'"), or {@code null} if the * input was {@code null} */ public static String quote(String str) { return str != null ? "'" + str + "'" : null; } /** * Turn the given Object into a String with single quotes if it is a String; * keeping the Object as-is else. * * @param obj * 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}, 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} * @return the capitalized String, {@code null} if null */ public static String capitalize(String str) { return changeFirstCharacterCase(str, true); } /** * Uncapitalize a {@code String}, 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} * @return the uncapitalized String, {@code null} 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; } StringBuilder sb = new StringBuilder(str.length()); if (capitalize) { sb.append(Character.toUpperCase(str.charAt(0))); } else { sb.append(Character.toLowerCase(str.charAt(0))); } sb.append(str.substring(1)); return sb.toString(); } /** * Extract the filename from the given path, e.g. "mypath/myfile.txt" -> * "myfile.txt". * * @param path * the file path (may be {@code null}) * @return the extracted filename, or {@code null} 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}) * @return the extracted filename extension, or {@code null} if none */ public static String getFilenameExtension(String path) { if (path == null) { return null; } int extIndex = path.lastIndexOf(EXTENSION_SEPARATOR); if (extIndex == -1) { return null; } int folderIndex = path.lastIndexOf(FOLDER_SEPARATOR); if (folderIndex > extIndex) { return null; } return path.substring(extIndex + 1); } /** * Strip the filename extension from the given path, e.g. * "mypath/myfile.txt" -> "mypath/myfile". * * @param path * the file path (may be {@code null}) * @return the path with stripped filename extension, or {@code null} if * none */ public static String stripFilenameExtension(String path) { if (path == null) { return null; } int extIndex = path.lastIndexOf(EXTENSION_SEPARATOR); if (extIndex == -1) { return path; } int folderIndex = path.lastIndexOf(FOLDER_SEPARATOR); if (folderIndex > extIndex) { return path; } return path.substring(0, extIndex); } /** * 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) { if (path == null) { return null; } 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); if (prefix.contains("/")) { prefix = ""; } else { pathToUse = pathToUse.substring(prefixIndex + 1); } } if (pathToUse.startsWith(FOLDER_SEPARATOR)) { prefix = prefix + FOLDER_SEPARATOR; pathToUse = pathToUse.substring(1); } String[] pathArray = delimitedListToStringArray(pathToUse, FOLDER_SEPARATOR); List<String> pathElements = new LinkedList<String>(); int tops = 0; for (int i = pathArray.length - 1; i >= 0; i--) { String element = pathArray[i]; if (CURRENT_PATH.equals(element)) { // Points to current directory - drop it. } else if (TOP_PATH.equals(element)) { // Registering top path found. tops++; } else { if (tops > 0) { // Merging path element with element corresponding to top // path. tops--; } else { // Normal path element found. pathElements.add(0, element); } } } // 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 comparison * @param path2 * second path for comparison * @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 {@code localeString} value into a {@link Locale}. * <p> * This is the inverse operation of {@link Locale#toString Locale's * toString}. * * @param localeString * the locale String, following {@code Locale's} * {@code toString()} format ("en", "en_UK", etc); also accepts * spaces as separators, as an alternative to underscores * @return a corresponding {@code Locale} instance * @throws IllegalArgumentException * in case of an invalid locale specification */ 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] : ""; validateLocalePart(language); validateLocalePart(country); String variant = ""; if (parts.length > 2) { // There is definitely a variant, and it is everything after the // country // code sans the separator between the country code and the variant. int endIndexOfCountryCode = localeString.indexOf(country, language.length()) + country.length(); // Strip off any leading '_' and whitespace, what's left is the // variant. variant = trimLeadingWhitespace(localeString.substring(endIndexOfCountryCode)); if (variant.startsWith("_")) { variant = trimLeadingCharacter(variant, '_'); } } return language.length() > 0 ? new Locale(language, country, variant) : null; } private static void validateLocalePart(String localePart) { for (int i = 0; i < localePart.length(); i++) { char ch = localePart.charAt(i); if (ch != '_' && ch != ' ' && !Character.isLetterOrDigit(ch)) { throw new IllegalArgumentException("Locale part \"" + localePart + "\" contains invalid characters"); } } } /** * Determine the RFC 3066 compliant language tag, as used for the HTTP * "Accept-Language" header. * * @param locale * the Locale to transform to a language tag * @return the RFC 3066 compliant language tag as String */ public static String toLanguageTag(Locale locale) { return locale.getLanguage() + (hasText(locale.getCountry()) ? "-" + locale.getCountry() : ""); } /** * Parse the given {@code timeZoneString} value into a {@link TimeZone}. * * @param timeZoneString * the time zone String, following * {@link TimeZone#getTimeZone(String)} but throwing * {@link IllegalArgumentException} in case of an invalid time * zone specification * @return a corresponding {@link TimeZone} instance * @throws IllegalArgumentException * in case of an invalid time zone specification */ public static TimeZone parseTimeZoneString(String timeZoneString) { TimeZone timeZone = TimeZone.getTimeZone(timeZoneString); if ("GMT".equals(timeZone.getID()) && !timeZoneString.startsWith("GMT")) { // We don't want that GMT fallback... throw new IllegalArgumentException("Invalid time zone specification '" + timeZoneString + "'"); } return timeZone; } /** * 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} if the passed-in Collection was * {@code null}) */ public static String[] toStringArray(Collection<String> collection) { if (collection == null) { return null; } return collection.toArray(new String[collection.size()]); } /** * Copy the given Enumeration into a String array. The Enumeration must * contain String elements only. * * @param enumeration * the Enumeration to copy * @return the String array ({@code null} if the passed-in Enumeration was * {@code null}) */ public static String[] toStringArray(Enumeration<String> enumeration) { if (enumeration == null) { return null; } List<String> list = Collections.list(enumeration); return list.toArray(new String[list.size()]); } /** * 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 delimiter (neither element includes the * delimiter); or {@code null} if the delimiter wasn't found in the * given input String */ public static String[] split(String toSplit, String delimiter) { if (!hasLength(toSplit) || !hasLength(delimiter)) { return null; } int offset = toSplit.indexOf(delimiter); if (offset < 0) { return null; } String beforeDelimiter = toSplit.substring(0, offset); String afterDelimiter = toSplit.substring(offset + delimiter.length()); return new String[] { beforeDelimiter, afterDelimiter }; } /** * Take an array Strings and split each element based on the given * delimiter. A {@code Properties} instance is then generated, with the left * of the delimiter providing the key, and the right of the delimiter * providing the value. * <p> * Will trim both the key and value before adding them to the * {@code Properties} instance. * * @param array * the array to process * @param delimiter * to split each element using (typically the equals symbol) * @return a {@code Properties} instance representing the array contents, or * {@code null} if the array to process was null or empty */ public static Properties splitArrayElementsIntoProperties(String[] array, String delimiter) { return splitArrayElementsIntoProperties(array, delimiter, null); } /** * Take an array Strings and split each element based on the given * delimiter. A {@code Properties} instance is then generated, with the left * of the delimiter providing the key, and the right of the delimiter * providing the value. * <p> * Will trim both the key and value before adding them to the * {@code Properties} instance. * * @param array * the array to process * @param delimiter * to split each element using (typically the equals symbol) * @param charsToDelete * one or more characters to remove from each element prior to * attempting the split operation (typically the quotation mark * symbol), or {@code null} if no removal should occur * @return a {@code Properties} instance representing the array contents, or * {@code null} if the array to process was {@code null} or empty */ public static Properties splitArrayElementsIntoProperties(String[] array, String delimiter, String charsToDelete) { if (array == null || array.length == 0) { return null; } Properties result = new Properties(); for (String element : array) { if (charsToDelete != null) { element = deleteAny(element, charsToDelete); } String[] splittedElement = split(element, delimiter); if (splittedElement == null) { continue; } result.setProperty(splittedElement[0].trim(), splittedElement[1].trim()); } return result; } /** * Tokenize the given String into a String array via a StringTokenizer. * Trims tokens and omits empty tokens. * <p> * The given delimiters string is supposed to consist of any number of * delimiter characters. Each of those characters can be used to separate * tokens. A delimiter is always a single character; for multi-character * delimiters, consider using {@code delimitedListToStringArray} * * @param str * the String to tokenize * @param delimiters * the delimiter characters, assembled as String (each of those * characters is individually considered as delimiter). * @return an array of the tokens * @see java.util.StringTokenizer * @see String#trim() * @see #delimitedListToStringArray */ public static String[] tokenizeToStringArray(String str, String delimiters) { return tokenizeToStringArray(str, delimiters, true, true); } /** * Tokenize the given String into a String array via a StringTokenizer. * <p> * The given delimiters string is supposed to consist of any number of * delimiter characters. Each of those characters can be used to separate * tokens. A delimiter is always a single character; for multi-character * delimiters, consider using {@code delimitedListToStringArray} * * @param str * the String to tokenize * @param delimiters * the delimiter characters, assembled as String (each of those * characters is individually considered as delimiter) * @param trimTokens * trim the tokens via String's {@code trim} * @param ignoreEmptyTokens * omit empty tokens from the result array (only applies to * tokens that are empty after trimming; StringTokenizer will not * consider subsequent delimiters as token in the first place). * @return an array of the tokens ({@code null} if the input String was * {@code null}) * @see java.util.StringTokenizer * @see String#trim() * @see #delimitedListToStringArray */ public static String[] tokenizeToStringArray(String str, String delimiters, boolean trimTokens, boolean ignoreEmptyTokens) { if (str == null) { return null; } StringTokenizer st = new StringTokenizer(str, delimiters); List<String> tokens = new ArrayList<String>(); while (st.hasMoreTokens()) { String token = st.nextToken(); if (trimTokens) { token = token.trim(); } if (!ignoreEmptyTokens || token.length() > 0) { tokens.add(token); } } return toStringArray(tokens); } /** * Take a String which is a delimited list and convert it to a String array. * <p> * A single delimiter can consists of more than one character: It will still * be considered as single delimiter string, rather than as bunch of * potential delimiter characters - in contrast to * {@code tokenizeToStringArray}. * * @param str * the input String * @param delimiter * the delimiter between elements (this is a single delimiter, * rather than a bunch individual delimiter characters) * @return an array of the tokens in the list * @see #tokenizeToStringArray */ public static String[] delimitedListToStringArray(String str, String delimiter) { return delimitedListToStringArray(str, delimiter, null); } /** * Take a String which is a delimited list and convert it to a String array. * <p> * A single delimiter can consists of more than one character: It will still * be considered as single delimiter string, rather than as bunch of * potential delimiter characters - in contrast to * {@code tokenizeToStringArray}. * * @param str * the input String * @param delimiter * the delimiter between elements (this is a single delimiter, * rather than a bunch individual delimiter characters) * @param charsToDelete * a set of characters to delete. Useful for deleting unwanted * line breaks: e.g. "\r\n\f" will delete all new lines and line * feeds in a String. * @return an array of the tokens in the list * @see #tokenizeToStringArray */ public static String[] delimitedListToStringArray(String str, String delimiter, String charsToDelete) { if (str == null) { return new String[0]; } if (delimiter == null) { return new String[] { str }; } List<String> result = new ArrayList<String>(); if ("".equals(delimiter)) { for (int i = 0; i < str.length(); i++) { result.add(deleteAny(str.substring(i, i + 1), charsToDelete)); } } else { int pos = 0; int delPos; while ((delPos = str.indexOf(delimiter, pos)) != -1) { result.add(deleteAny(str.substring(pos, delPos), charsToDelete)); pos = delPos + delimiter.length(); } if (str.length() > 0 && pos <= str.length()) { // Add rest of String, but not in case of empty input. result.add(deleteAny(str.substring(pos), charsToDelete)); } } return toStringArray(result); } /** * Convert a CSV list into an array of Strings. * * @param str * the input String * @return an array of Strings, or the empty array in case of empty input */ public static String[] commaDelimitedListToStringArray(String str) { return delimitedListToStringArray(str, ","); } /** * Convenience method to convert a CSV string list to a set. Note that this * will suppress duplicates. * * @param str * the input String * @return a Set of String entries in the list */ public static Set<String> commaDelimitedListToSet(String str) { Set<String> set = new TreeSet<String>(); String[] tokens = commaDelimitedListToStringArray(str); for (String token : tokens) { set.add(token); } return set; } /** * Convenience method to return a Collection as a delimited (e.g. CSV) * String. E.g. useful for {@code toString()} implementations. * * @param coll * the Collection to display * @param delim * the delimiter to use (probably a ",") * @param prefix * the String to start each element with * @param suffix * the String to end each element with * @return the delimited String */ public static String collectionToDelimitedString(Collection<?> coll, String delim, String prefix, String suffix) { if (coll.isEmpty()) { return ""; } StringBuilder sb = new StringBuilder(); Iterator<?> it = coll.iterator(); while (it.hasNext()) { sb.append(prefix).append(it.next()).append(suffix); if (it.hasNext()) { sb.append(delim); } } return sb.toString(); } /** * Convenience method to return a Collection as a delimited (e.g. CSV) * String. E.g. useful for {@code toString()} implementations. * * @param coll * the Collection to display * @param delim * the delimiter to use (probably a ",") * @return the delimited String */ public static String collectionToDelimitedString(Collection<?> coll, String delim) { return collectionToDelimitedString(coll, delim, "", ""); } /** * Convenience method to return a Collection as a CSV String. E.g. useful * for {@code toString()} implementations. * * @param coll * the Collection to display * @return the delimited String */ public static String collectionToCommaDelimitedString(Collection<?> coll) { return collectionToDelimitedString(coll, ","); } /** * Convenience method to return a String array as a delimited (e.g. CSV) * String. E.g. useful for {@code toString()} implementations. * * @param arr * the array to display * @param delim * the delimiter to use (probably a ",") * @return the delimited String */ public static String arrayToDelimitedString(Object[] arr, String delim) { if (arr == null || arr.length ==0) { return ""; } if (arr.length == 1) { return (String) arr[0]; } StringBuilder sb = new StringBuilder(); for (int i = 0; i < arr.length; i++) { if (i > 0) { sb.append(delim); } sb.append(arr[i]); } return sb.toString(); } /** * Convenience method to return a String array as a CSV String. E.g. useful * for {@code toString()} implementations. * * @param arr * the array to display * @return the delimited String */ public static String arrayToCommaDelimitedString(Object[] arr) { return arrayToDelimitedString(arr, ","); } }