Package yakworks.util

Class StringUtils

  • public abstract class StringUtils
extends java.lang.Object
    Miscellaneous String utility methods.

    Mainly for internal use within the framework; consider Apache's Commons Lang for a more comprehensive suite of String utilities.

    This class delivers some simple functionality that should really be provided by the core Java String and StringBuilder classes. It also provides easy-to-use methods to convert between delimited strings, such as CSV strings, and collections and arrays.

    Since:
    16 April 2001

    • Constructor Summary

      Constructors 
      Constructor Description
      StringUtils()  

    • Method Summary

      All Methods Static Methods Concrete Methods Deprecated Methods 
      Modifier and Type Method Description
      static java.lang.String[] addStringToArray​(java.lang.String[] array, java.lang.String str)
      Append the given String to the given String array, returning a new array consisting of the input array contents plus the given String.
      static java.lang.String applyRelativePath​(java.lang.String path, java.lang.String relativePath)
      Apply the given relative path to the given Java resource path, assuming standard Java folder separation (i.e.
      static java.lang.String arrayToCommaDelimitedString​(java.lang.Object[] arr)
      Convert a String array into a comma delimited String (i.e., CSV).
      static java.lang.String arrayToDelimitedString​(java.lang.Object[] arr, java.lang.String delim)
      Convert a String array into a delimited String (e.g.
      static java.lang.String capitalize​(java.lang.String str)
      Capitalize a String, changing the first letter to upper case as per Character.toUpperCase(char).
      static java.lang.String cleanPath​(java.lang.String path)
      Normalize the path by suppressing sequences like "path/.." and inner simple dots.
      static java.lang.String collectionToCommaDelimitedString​(java.util.Collection<?> coll)
      Convert a Collection into a delimited String (e.g., CSV).
      static java.lang.String collectionToDelimitedString​(java.util.Collection<?> coll, java.lang.String delim)
      Convert a Collection into a delimited String (e.g.
      static java.lang.String collectionToDelimitedString​(java.util.Collection<?> coll, java.lang.String delim, java.lang.String prefix, java.lang.String suffix)
      Convert a Collection to a delimited String (e.g.
      static java.util.Set<java.lang.String> commaDelimitedListToSet​(java.lang.String str)
      Convert a comma delimited list (e.g., a row from a CSV file) into a set.
      static java.lang.String[] commaDelimitedListToStringArray​(java.lang.String str)
      Convert a comma delimited list (e.g., a row from a CSV file) into an array of strings.
      static java.lang.String[] concatenateStringArrays​(java.lang.String[] array1, java.lang.String[] array2)
      Concatenate the given String arrays into one, with overlapping array elements included twice.
      static boolean containsWhitespace​(java.lang.CharSequence str)
      Check whether the given CharSequence contains any whitespace characters.
      static boolean containsWhitespace​(java.lang.String str)
      Check whether the given String contains any whitespace characters.
      static int countOccurrencesOf​(java.lang.String str, java.lang.String sub)
      Count the occurrences of the substring sub in string str.
      static java.lang.String delete​(java.lang.String inString, java.lang.String pattern)
      Delete all occurrences of the given substring.
      static java.lang.String deleteAny​(java.lang.String inString, java.lang.String charsToDelete)
      Delete any character in a given String.
      static java.lang.String[] delimitedListToStringArray​(java.lang.String str, java.lang.String delimiter)
      Take a String that is a delimited list and convert it into a String array.
      static java.lang.String[] delimitedListToStringArray​(java.lang.String str, java.lang.String delimiter, java.lang.String charsToDelete)
      Take a String that is a delimited list and convert it into a String array.
      static boolean endsWithIgnoreCase​(java.lang.String str, java.lang.String suffix)
      Test if the given String ends with the specified suffix, ignoring upper/lower case.
      static java.lang.String getFilename​(java.lang.String path)
      Extract the filename from the given Java resource path, e.g.
      static java.lang.String getFilenameExtension​(java.lang.String path)
      Extract the filename extension from the given Java resource path, e.g.
      static boolean hasLength​(java.lang.CharSequence str)
      Check that the given CharSequence is neither null nor of length 0.
      static boolean hasLength​(java.lang.String str)
      Check that the given String is neither null nor of length 0.
      static boolean hasText​(java.lang.CharSequence str)
      Check whether the given CharSequence contains actual text.
      static boolean hasText​(java.lang.String str)
      Check whether the given String contains actual text.
      static boolean isEmpty​(java.lang.Object str)
      Deprecated.
      as of 5.3, in favor of hasLength(String) and hasText(String) (or ObjectUtils.isEmpty(Object))
      static boolean matchesCharacter​(java.lang.String str, char singleCharacter)
      Test if the given String matches the given single character.
      static java.lang.String[] mergeStringArrays​(java.lang.String[] array1, java.lang.String[] array2)
      Deprecated.
      as of 4.3.15, in favor of manual merging via LinkedHashSet (with every entry included at most once, even entries within the first array)
      static java.util.Locale parseLocale​(java.lang.String localeValue)
      Parse the given String value into a Locale, accepting the Locale.toString() format as well as BCP 47 language tags as specified by Locale.forLanguageTag(java.lang.String).
      static java.util.Locale parseLocaleString​(java.lang.String localeString)
      Parse the given String representation into a Locale.
      static java.util.TimeZone parseTimeZoneString​(java.lang.String timeZoneString)
      Parse the given timeZoneString value into a TimeZone.
      static boolean pathEquals​(java.lang.String path1, java.lang.String path2)
      Compare two paths after normalization of them.
      static java.lang.String quote​(java.lang.String str)
      Quote the given String with single quotes.
      static java.lang.Object quoteIfString​(java.lang.Object obj)
      Turn the given Object into a String with single quotes if it is a String; keeping the Object as-is else.
      static java.lang.String[] removeDuplicateStrings​(java.lang.String[] array)
      Remove duplicate strings from the given array.
      static java.lang.String replace​(java.lang.String inString, java.lang.String oldPattern, java.lang.String newPattern)
      Replace all occurrences of a substring within a string with another string.
      static java.lang.String[] sortStringArray​(java.lang.String[] array)
      Sort the given String array if necessary.
      static java.lang.String[] split​(java.lang.String toSplit, java.lang.String delimiter)
      Split a String at the first occurrence of the delimiter.
      static java.util.Properties splitArrayElementsIntoProperties​(java.lang.String[] array, java.lang.String delimiter)
      Take an array of strings and split each element based on the given delimiter.
      static java.util.Properties splitArrayElementsIntoProperties​(java.lang.String[] array, java.lang.String delimiter, java.lang.String charsToDelete)
      Take an array of strings and split each element based on the given delimiter.
      static boolean startsWithIgnoreCase​(java.lang.String str, java.lang.String prefix)
      Test if the given String starts with the specified prefix, ignoring upper/lower case.
      static java.lang.String stripFilenameExtension​(java.lang.String path)
      Strip the filename extension from the given Java resource path, e.g.
      static boolean substringMatch​(java.lang.CharSequence str, int index, java.lang.CharSequence substring)
      Test whether the given string matches the given substring at the given index.
      static java.lang.String[] tokenizeToStringArray​(java.lang.String str, java.lang.String delimiters)
      Tokenize the given String into a String array via a StringTokenizer.
      static java.lang.String[] tokenizeToStringArray​(java.lang.String str, java.lang.String delimiters, boolean trimTokens, boolean ignoreEmptyTokens)
      Tokenize the given String into a String array via a StringTokenizer.
      static java.lang.String toLanguageTag​(java.util.Locale locale)
      Deprecated.
      as of 5.0.4, in favor of Locale.toLanguageTag()
      static java.lang.String[] toStringArray​(java.util.Collection<java.lang.String> collection)
      Copy the given Collection into a String array.
      static java.lang.String[] toStringArray​(java.util.Enumeration<java.lang.String> enumeration)
      Copy the given Enumeration into a String array.
      static java.lang.CharSequence trimAllWhitespace​(java.lang.CharSequence text)
      Trim all whitespace from the given CharSequence: leading, trailing, and in between characters.
      static java.lang.String trimAllWhitespace​(java.lang.String str)
      Trim all whitespace from the given String: leading, trailing, and in between characters.
      static java.lang.String[] trimArrayElements​(java.lang.String[] array)
      Trim the elements of the given String array, calling String.trim() on each non-null element.
      static java.lang.String trimLeadingCharacter​(java.lang.String str, char leadingCharacter)
      Trim all occurrences of the supplied leading character from the given String.
      static java.lang.String trimLeadingWhitespace​(java.lang.String str)
      Trim leading whitespace from the given String.
      static java.lang.String trimTrailingCharacter​(java.lang.String str, char trailingCharacter)
      Trim all occurrences of the supplied trailing character from the given String.
      static java.lang.String trimTrailingWhitespace​(java.lang.String str)
      Trim trailing whitespace from the given String.
      static java.lang.String trimWhitespace​(java.lang.String str)
      Trim leading and trailing whitespace from the given String.
      static java.lang.String uncapitalize​(java.lang.String str)
      Uncapitalize a String, changing the first letter to lower case as per Character.toLowerCase(char).
      static java.lang.String unqualify​(java.lang.String qualifiedName)
      Unqualify a string qualified by a '.' dot character.
      static java.lang.String unqualify​(java.lang.String qualifiedName, char separator)
      Unqualify a string qualified by a separator character.
      static java.lang.String uriDecode​(java.lang.String source, java.nio.charset.Charset charset)
      Decode the given encoded URI component value.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • StringUtils

        public StringUtils()

    • Method Detail

      • isEmpty

        @Deprecated
public static boolean isEmpty​(@Nullable
                              java.lang.Object str)
        Deprecated.
        as of 5.3, in favor of hasLength(String) and hasText(String) (or ObjectUtils.isEmpty(Object))
        Check whether the given object (possibly a String) is empty. This is effectively a shortcut for !hasLength(String).

        This method accepts any Object as an argument, comparing it to null and the empty String. As a consequence, this method will never return true for a non-null non-String object.

        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.

        Note: If the object is typed to String upfront, prefer hasLength(String) or hasText(String) instead.

        Parameters:
        str - the candidate object (possibly a String)
        Since:
        3.2.1

      • hasLength

        public static boolean hasLength​(@Nullable
                                java.lang.CharSequence str)
        Check that the given CharSequence is neither null nor of length 0.

        Note: this method returns true for a CharSequence that purely consists of whitespace. 

         StringUtils.hasLength(null) = false
 StringUtils.hasLength("") = false
 StringUtils.hasLength(" ") = true
 StringUtils.hasLength("Hello") = true
        Parameters:
        str - the CharSequence to check (may be null)
        Returns:
        true if the CharSequence is not null and has length
        See Also:
        hasLength(String), hasText(CharSequence)

      • hasLength

        public static boolean hasLength​(@Nullable
                                java.lang.String str)
        Check that the given String is neither null nor of length 0.

        Note: this method returns true for a String that purely consists of whitespace.

        Parameters:
        str - the String to check (may be null)
        Returns:
        true if the String is not null and has length
        See Also:
        hasLength(CharSequence), hasText(String)

      • hasText

        public static boolean hasText​(@Nullable
                              java.lang.CharSequence str)
        Check whether the given CharSequence contains actual text.

        More specifically, this method returns true if the CharSequence is not null, its length is greater than 0, and it contains at least one non-whitespace character. 

         StringUtils.hasText(null) = false
 StringUtils.hasText("") = false
 StringUtils.hasText(" ") = false
 StringUtils.hasText("12345") = true
 StringUtils.hasText(" 12345 ") = true
        Parameters:
        str - the CharSequence to check (may be null)
        Returns:
        true if the CharSequence is not null, its length is greater than 0, and it does not contain whitespace only
        See Also:
        hasText(String), hasLength(CharSequence), Character.isWhitespace(char)

      • hasText

        public static boolean hasText​(@Nullable
                              java.lang.String str)
        Check whether the given String contains actual text.

        More specifically, this method returns true if the String is not null, its length is greater than 0, and it contains at least one non-whitespace character.

        Parameters:
        str - the String to check (may be null)
        Returns:
        true if the String is not null, its length is greater than 0, and it does not contain whitespace only
        See Also:
        hasText(CharSequence), hasLength(String), Character.isWhitespace(char)

      • containsWhitespace

        public static boolean containsWhitespace​(@Nullable
                                         java.lang.CharSequence str)
        Check whether the given CharSequence contains any whitespace characters.
        Parameters:
        str - the CharSequence to check (may be null)
        Returns:
        true if the CharSequence is not empty and contains at least 1 whitespace character
        See Also:
        Character.isWhitespace(char)

      • containsWhitespace

        public static boolean containsWhitespace​(@Nullable
                                         java.lang.String str)
        Check whether the given String contains any whitespace characters.
        Parameters:
        str - the String to check (may be null)
        Returns:
        true if the String is not empty and contains at least 1 whitespace character
        See Also:
        containsWhitespace(CharSequence)

      • trimWhitespace

        public static java.lang.String trimWhitespace​(java.lang.String str)
        Trim leading and trailing whitespace from the given String.
        Parameters:
        str - the String to check
        Returns:
        the trimmed String
        See Also:
        Character.isWhitespace(char)

      • trimAllWhitespace

        public static java.lang.CharSequence trimAllWhitespace​(java.lang.CharSequence text)
        Trim all whitespace from the given CharSequence: leading, trailing, and in between characters.
        Parameters:
        text - the CharSequence to check
        Returns:
        the trimmed CharSequence
        Since:
        5.3.22
        See Also:
        trimAllWhitespace(String), Character.isWhitespace(char)

      • trimAllWhitespace

        public static java.lang.String trimAllWhitespace​(java.lang.String str)
        Trim all whitespace from the given String: leading, trailing, and in between characters.
        Parameters:
        str - the String to check
        Returns:
        the trimmed String
        See Also:
        trimAllWhitespace(CharSequence), Character.isWhitespace(char)

      • trimLeadingWhitespace

        public static java.lang.String trimLeadingWhitespace​(java.lang.String str)
        Trim leading whitespace from the given String.
        Parameters:
        str - the String to check
        Returns:
        the trimmed String
        See Also:
        Character.isWhitespace(char)

      • trimTrailingWhitespace

        public static java.lang.String trimTrailingWhitespace​(java.lang.String str)
        Trim trailing whitespace from the given String.
        Parameters:
        str - the String to check
        Returns:
        the trimmed String
        See Also:
        Character.isWhitespace(char)

      • trimLeadingCharacter

        public static java.lang.String trimLeadingCharacter​(java.lang.String str,
                                                    char leadingCharacter)
        Trim all occurrences of the supplied leading character from the given String.
        Parameters:
        str - the String to check
        leadingCharacter - the leading character to be trimmed
        Returns:
        the trimmed String

      • trimTrailingCharacter

        public static java.lang.String trimTrailingCharacter​(java.lang.String str,
                                                     char trailingCharacter)
        Trim all occurrences of the supplied trailing character from the given String.
        Parameters:
        str - the String to check
        trailingCharacter - the trailing character to be trimmed
        Returns:
        the trimmed String

      • matchesCharacter

        public static boolean matchesCharacter​(@Nullable
                                       java.lang.String str,
                                       char singleCharacter)
        Test if the given String matches the given single character.
        Parameters:
        str - the String to check
        singleCharacter - the character to compare to
        Since:
        5.2.9

      • startsWithIgnoreCase

        public static boolean startsWithIgnoreCase​(@Nullable
                                           java.lang.String str,
                                           @Nullable
                                           java.lang.String prefix)
        Test if the given String starts with the specified prefix, ignoring upper/lower case.
        Parameters:
        str - the String to check
        prefix - the prefix to look for
        See Also:
        String.startsWith(java.lang.String, int)

      • endsWithIgnoreCase

        public static boolean endsWithIgnoreCase​(@Nullable
                                         java.lang.String str,
                                         @Nullable
                                         java.lang.String suffix)
        Test if the given String ends with the specified suffix, ignoring upper/lower case.
        Parameters:
        str - the String to check
        suffix - the suffix to look for
        See Also:
        String.endsWith(java.lang.String)

      • substringMatch

        public static boolean substringMatch​(java.lang.CharSequence str,
                                     int index,
                                     java.lang.CharSequence substring)
        Test whether the given string matches the given substring at the given index.
        Parameters:
        str - the original string (or StringBuilder)
        index - the index in the original string to start matching against
        substring - the substring to match at the given index

      • countOccurrencesOf

        public static int countOccurrencesOf​(java.lang.String str,
                                     java.lang.String sub)
        Count the occurrences of the substring sub in string str.
        Parameters:
        str - string to search in
        sub - string to search for

      • replace

        public static java.lang.String replace​(java.lang.String inString,
                                       java.lang.String oldPattern,
                                       @Nullable
                                       java.lang.String newPattern)
        Replace all occurrences of a substring within a string with another string.
        Parameters:
        inString - String to examine
        oldPattern - String to replace
        newPattern - String to insert
        Returns:
        a String with the replacements

      • delete

        public static java.lang.String delete​(java.lang.String inString,
                                      java.lang.String pattern)
        Delete all occurrences of the given substring.
        Parameters:
        inString - the original String
        pattern - the pattern to delete all occurrences of
        Returns:
        the resulting String

      • deleteAny

        public static java.lang.String deleteAny​(java.lang.String inString,
                                         @Nullable
                                         java.lang.String charsToDelete)
        Delete any character in a given String.
        Parameters:
        inString - the original String
        charsToDelete - a set of characters to delete. E.g. "az\n" will delete 'a's, 'z's and new lines.
        Returns:
        the resulting String

      • quote

        @Nullable
public static java.lang.String quote​(@Nullable
                                     java.lang.String str)
        Quote the given String with single quotes.
        Parameters:
        str - the input String (e.g. "myString")
        Returns:
        the quoted String (e.g. "'myString'"), or null if the input was null

      • quoteIfString

        @Nullable
public static java.lang.Object quoteIfString​(@Nullable
                                             java.lang.Object obj)
        Turn the given Object into a String with single quotes if it is a String; keeping the Object as-is else.
        Parameters:
        obj - the input Object (e.g. "myString")
        Returns:
        the quoted String (e.g. "'myString'"), or the input object as-is if not a String

      • unqualify

        public static java.lang.String unqualify​(java.lang.String qualifiedName)
        Unqualify a string qualified by a '.' dot character. For example, "this.name.is.qualified", returns "qualified".
        Parameters:
        qualifiedName - the qualified name

      • unqualify

        public static java.lang.String unqualify​(java.lang.String qualifiedName,
                                         char separator)
        Unqualify a string qualified by a separator character. For example, "this:name:is:qualified" returns "qualified" if using a ':' separator.
        Parameters:
        qualifiedName - the qualified name
        separator - the separator

      • capitalize

        public static java.lang.String capitalize​(java.lang.String str)
        Capitalize a String, changing the first letter to upper case as per Character.toUpperCase(char). No other letters are changed.
        Parameters:
        str - the String to capitalize
        Returns:
        the capitalized String

      • uncapitalize

        public static java.lang.String uncapitalize​(java.lang.String str)
        Uncapitalize a String, changing the first letter to lower case as per Character.toLowerCase(char). No other letters are changed.
        Parameters:
        str - the String to uncapitalize
        Returns:
        the uncapitalized String

      • getFilename

        @Nullable
public static java.lang.String getFilename​(@Nullable
                                           java.lang.String path)
        Extract the filename from the given Java resource path, e.g. "mypath/myfile.txt" &rarr; "myfile.txt".
        Parameters:
        path - the file path (may be null)
        Returns:
        the extracted filename, or null if none

      • getFilenameExtension

        @Nullable
public static java.lang.String getFilenameExtension​(@Nullable
                                                    java.lang.String path)
        Extract the filename extension from the given Java resource path, e.g. "mypath/myfile.txt" → "txt".
        Parameters:
        path - the file path (may be null)
        Returns:
        the extracted filename extension, or null if none

      • stripFilenameExtension

        public static java.lang.String stripFilenameExtension​(java.lang.String path)
        Strip the filename extension from the given Java resource path, e.g. "mypath/myfile.txt" → "mypath/myfile".
        Parameters:
        path - the file path
        Returns:
        the path with stripped filename extension

      • applyRelativePath

        public static java.lang.String applyRelativePath​(java.lang.String path,
                                                 java.lang.String relativePath)
        Apply the given relative path to the given Java resource path, assuming standard Java folder separation (i.e. "/" separators).
        Parameters:
        path - the path to start from (usually a full file path)
        relativePath - the relative path to apply (relative to the full file path above)
        Returns:
        the full file path that results from applying the relative path

      • cleanPath

        public static java.lang.String cleanPath​(java.lang.String path)
        Normalize the path by suppressing sequences like "path/.." and inner simple dots.

        The result is convenient for path comparison. For other uses, notice that Windows separators ("\") are replaced by simple slashes.

        NOTE that cleanPath should not be depended upon in a security context. Other mechanisms should be used to prevent path-traversal issues.

        Parameters:
        path - the original path
        Returns:
        the normalized path

      • pathEquals

        public static boolean pathEquals​(java.lang.String path1,
                                 java.lang.String path2)
        Compare two paths after normalization of them.
        Parameters:
        path1 - first path for comparison
        path2 - second path for comparison
        Returns:
        whether the two paths are equivalent after normalization

      • uriDecode

        public static java.lang.String uriDecode​(java.lang.String source,
                                         java.nio.charset.Charset charset)
        Decode the given encoded URI component value. Based on the following rules:
        • Alphanumeric characters "a" through "z", "A" through "Z", and "0" through "9" stay the same.
        • Special characters "-", "_", ".", and "*" stay the same.
        • A sequence "%<i>xy</i>" is interpreted as a hexadecimal representation of the character.
        Parameters:
        source - the encoded String
        charset - the character set
        Returns:
        the decoded value
        Throws:
        java.lang.IllegalArgumentException - when the given source contains invalid encoded sequences
        Since:
        5.0
        See Also:
        URLDecoder.decode(String, String)

      • parseLocale

        @Nullable
public static java.util.Locale parseLocale​(java.lang.String localeValue)
        Parse the given String value into a Locale, accepting the Locale.toString() format as well as BCP 47 language tags as specified by Locale.forLanguageTag(java.lang.String).
        Parameters:
        localeValue - the locale value: following either Locale's toString() format ("en", "en_UK", etc), also accepting spaces as separators (as an alternative to underscores), or BCP 47 (e.g. "en-UK")
        Returns:
        a corresponding Locale instance, or null if none
        Throws:
        java.lang.IllegalArgumentException - in case of an invalid locale specification
        Since:
        5.0.4
        See Also:
        parseLocaleString(java.lang.String), Locale.forLanguageTag(java.lang.String)

      • parseLocaleString

        @Nullable
public static java.util.Locale parseLocaleString​(java.lang.String localeString)
        Parse the given String representation into a Locale.

        For many parsing scenarios, this is an inverse operation of Locale's toString, in a lenient sense. This method does not aim for strict Locale design compliance; it is rather specifically tailored for typical Spring parsing needs.

        Note: This delegate does not accept the BCP 47 language tag format. Please use parseLocale(java.lang.String) for lenient parsing of both formats.

        Parameters:
        localeString - the locale String: following Locale's toString() format ("en", "en_UK", etc), also accepting spaces as separators (as an alternative to underscores)
        Returns:
        a corresponding Locale instance, or null if none
        Throws:
        java.lang.IllegalArgumentException - in case of an invalid locale specification

      • toLanguageTag

        @Deprecated
public static java.lang.String toLanguageTag​(java.util.Locale locale)
        Deprecated.
        as of 5.0.4, in favor of Locale.toLanguageTag()
        Determine the RFC 3066 compliant language tag, as used for the HTTP "Accept-Language" header.
        Parameters:
        locale - the Locale to transform to a language tag
        Returns:
        the RFC 3066 compliant language tag as String

      • parseTimeZoneString

        public static java.util.TimeZone parseTimeZoneString​(java.lang.String timeZoneString)
        Parse the given timeZoneString value into a TimeZone.
        Parameters:
        timeZoneString - the time zone String, following TimeZone.getTimeZone(String) but throwing IllegalArgumentException in case of an invalid time zone specification
        Returns:
        a corresponding TimeZone instance
        Throws:
        java.lang.IllegalArgumentException - in case of an invalid time zone specification

      • toStringArray

        public static java.lang.String[] toStringArray​(@Nullable
                                               java.util.Collection<java.lang.String> collection)
        Copy the given Collection into a String array.

        The Collection must contain String elements only.

        Parameters:
        collection - the Collection to copy (potentially null or empty)
        Returns:
        the resulting String array

      • toStringArray

        public static java.lang.String[] toStringArray​(@Nullable
                                               java.util.Enumeration<java.lang.String> enumeration)
        Copy the given Enumeration into a String array.

        The Enumeration must contain String elements only.

        Parameters:
        enumeration - the Enumeration to copy (potentially null or empty)
        Returns:
        the resulting String array

      • addStringToArray

        public static java.lang.String[] addStringToArray​(@Nullable
                                                  java.lang.String[] array,
                                                  java.lang.String str)
        Append the given String to the given String array, returning a new array consisting of the input array contents plus the given String.
        Parameters:
        array - the array to append to (can be null)
        str - the String to append
        Returns:
        the new array (never null)

      • concatenateStringArrays

        @Nullable
public static java.lang.String[] concatenateStringArrays​(@Nullable
                                                         java.lang.String[] array1,
                                                         @Nullable
                                                         java.lang.String[] array2)
        Concatenate the given String arrays into one, with overlapping array elements included twice.

        The order of elements in the original arrays is preserved.

        Parameters:
        array1 - the first array (can be null)
        array2 - the second array (can be null)
        Returns:
        the new array (null if both given arrays were null)

      • mergeStringArrays

        @Deprecated
@Nullable
public static java.lang.String[] mergeStringArrays​(@Nullable
                                                   java.lang.String[] array1,
                                                   @Nullable
                                                   java.lang.String[] array2)
        Deprecated.
        as of 4.3.15, in favor of manual merging via LinkedHashSet (with every entry included at most once, even entries within the first array)
        Merge the given String arrays into one, with overlapping array elements only included once.

        The order of elements in the original arrays is preserved (with the exception of overlapping elements, which are only included on their first occurrence).

        Parameters:
        array1 - the first array (can be null)
        array2 - the second array (can be null)
        Returns:
        the new array (null if both given arrays were null)

      • sortStringArray

        public static java.lang.String[] sortStringArray​(java.lang.String[] array)
        Sort the given String array if necessary.
        Parameters:
        array - the original array (potentially empty)
        Returns:
        the array in sorted form (never null)

      • trimArrayElements

        public static java.lang.String[] trimArrayElements​(java.lang.String[] array)
        Trim the elements of the given String array, calling String.trim() on each non-null element.
        Parameters:
        array - the original String array (potentially empty)
        Returns:
        the resulting array (of the same size) with trimmed elements

      • removeDuplicateStrings

        public static java.lang.String[] removeDuplicateStrings​(java.lang.String[] array)
        Remove duplicate strings from the given array.

        As of 4.2, it preserves the original order, as it uses a LinkedHashSet.

        Parameters:
        array - the String array (potentially empty)
        Returns:
        an array without duplicates, in natural sort order

      • split

        @Nullable
public static java.lang.String[] split​(@Nullable
                                       java.lang.String toSplit,
                                       @Nullable
                                       java.lang.String delimiter)
        Split a String at the first occurrence of the delimiter. Does not include the delimiter in the result.
        Parameters:
        toSplit - the string to split (potentially null or empty)
        delimiter - to split the string up with (potentially null or empty)
        Returns:
        a two element array with index 0 being before the delimiter, and index 1 being after the delimiter (neither element includes the delimiter); or null if the delimiter wasn't found in the given input String

      • splitArrayElementsIntoProperties

        @Nullable
public static java.util.Properties splitArrayElementsIntoProperties​(java.lang.String[] array,
                                                                    java.lang.String delimiter)
        Take an array of strings and split each element based on the given delimiter. A Properties instance is then generated, with the left of the delimiter providing the key, and the right of the delimiter providing the value.

        Will trim both the key and value before adding them to the Properties.

        Parameters:
        array - the array to process
        delimiter - to split each element using (typically the equals symbol)
        Returns:
        a Properties instance representing the array contents, or null if the array to process was null or empty

      • splitArrayElementsIntoProperties

        @Nullable
public static java.util.Properties splitArrayElementsIntoProperties​(java.lang.String[] array,
                                                                    java.lang.String delimiter,
                                                                    @Nullable
                                                                    java.lang.String charsToDelete)
        Take an array of strings and split each element based on the given delimiter. A Properties instance is then generated, with the left of the delimiter providing the key, and the right of the delimiter providing the value.

        Will trim both the key and value before adding them to the Properties instance.

        Parameters:
        array - the array to process
        delimiter - to split each element using (typically the equals symbol)
        charsToDelete - one or more characters to remove from each element prior to attempting the split operation (typically the quotation mark symbol), or null if no removal should occur
        Returns:
        a Properties instance representing the array contents, or null if the array to process was null or empty

      • tokenizeToStringArray

        public static java.lang.String[] tokenizeToStringArray​(@Nullable
                                                       java.lang.String str,
                                                       java.lang.String delimiters)
        Tokenize the given String into a String array via a StringTokenizer.

        Trims tokens and omits empty tokens.

        The given delimiters string can 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 delimitedListToStringArray(java.lang.String, java.lang.String).

        Parameters:
        str - the String to tokenize (potentially null or empty)
        delimiters - the delimiter characters, assembled as a String (each of the characters is individually considered as a delimiter)
        Returns:
        an array of the tokens
        See Also:
        StringTokenizer, String.trim(), delimitedListToStringArray(java.lang.String, java.lang.String)

      • tokenizeToStringArray

        public static java.lang.String[] tokenizeToStringArray​(@Nullable
                                                       java.lang.String str,
                                                       java.lang.String delimiters,
                                                       boolean trimTokens,
                                                       boolean ignoreEmptyTokens)
        Tokenize the given String into a String array via a StringTokenizer.

        The given delimiters string can 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 delimitedListToStringArray(java.lang.String, java.lang.String).

        Parameters:
        str - the String to tokenize (potentially null or empty)
        delimiters - the delimiter characters, assembled as a String (each of the characters is individually considered as a delimiter)
        trimTokens - trim the tokens via String.trim()
        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).
        Returns:
        an array of the tokens
        See Also:
        StringTokenizer, String.trim(), delimitedListToStringArray(java.lang.String, java.lang.String)

      • delimitedListToStringArray

        public static java.lang.String[] delimitedListToStringArray​(@Nullable
                                                            java.lang.String str,
                                                            @Nullable
                                                            java.lang.String delimiter)
        Take a String that is a delimited list and convert it into a String array.

        A single delimiter may consist of more than one character, but it will still be considered as a single delimiter string, rather than as a bunch of potential delimiter characters, in contrast to tokenizeToStringArray(java.lang.String, java.lang.String).

        Parameters:
        str - the input String (potentially null or empty)
        delimiter - the delimiter between elements (this is a single delimiter, rather than a bunch individual delimiter characters)
        Returns:
        an array of the tokens in the list
        See Also:
        tokenizeToStringArray(java.lang.String, java.lang.String)

      • delimitedListToStringArray

        public static java.lang.String[] delimitedListToStringArray​(@Nullable
                                                            java.lang.String str,
                                                            @Nullable
                                                            java.lang.String delimiter,
                                                            @Nullable
                                                            java.lang.String charsToDelete)
        Take a String that is a delimited list and convert it into a String array.

        A single delimiter may consist of more than one character, but it will still be considered as a single delimiter string, rather than as a bunch of potential delimiter characters, in contrast to tokenizeToStringArray(java.lang.String, java.lang.String).

        Parameters:
        str - the input String (potentially null or empty)
        delimiter - the delimiter between elements (this is a single delimiter, rather than a bunch individual delimiter characters)
        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
        Returns:
        an array of the tokens in the list
        See Also:
        tokenizeToStringArray(java.lang.String, java.lang.String)

      • commaDelimitedListToStringArray

        public static java.lang.String[] commaDelimitedListToStringArray​(@Nullable
                                                                 java.lang.String str)
        Convert a comma delimited list (e.g., a row from a CSV file) into an array of strings.
        Parameters:
        str - the input String (potentially null or empty)
        Returns:
        an array of strings, or the empty array in case of empty input

      • commaDelimitedListToSet

        public static java.util.Set<java.lang.String> commaDelimitedListToSet​(@Nullable
                                                                      java.lang.String str)
        Convert a comma delimited list (e.g., a row from a CSV file) into a set.

        Note that this will suppress duplicates, and as of 4.2, the elements in the returned set will preserve the original order in a LinkedHashSet.

        Parameters:
        str - the input String (potentially null or empty)
        Returns:
        a set of String entries in the list
        See Also:
        removeDuplicateStrings(String[])

      • collectionToDelimitedString

        public static java.lang.String collectionToDelimitedString​(@Nullable
                                                           java.util.Collection<?> coll,
                                                           java.lang.String delim,
                                                           java.lang.String prefix,
                                                           java.lang.String suffix)
        Convert a Collection to a delimited String (e.g. CSV).

        Useful for toString() implementations.

        Parameters:
        coll - the Collection to convert (potentially null or empty)
        delim - the delimiter to use (typically a ",")
        prefix - the String to start each element with
        suffix - the String to end each element with
        Returns:
        the delimited String

      • collectionToDelimitedString

        public static java.lang.String collectionToDelimitedString​(@Nullable
                                                           java.util.Collection<?> coll,
                                                           java.lang.String delim)
        Convert a Collection into a delimited String (e.g. CSV).

        Useful for toString() implementations.

        Parameters:
        coll - the Collection to convert (potentially null or empty)
        delim - the delimiter to use (typically a ",")
        Returns:
        the delimited String

      • collectionToCommaDelimitedString

        public static java.lang.String collectionToCommaDelimitedString​(@Nullable
                                                                java.util.Collection<?> coll)
        Convert a Collection into a delimited String (e.g., CSV).

        Useful for toString() implementations.

        Parameters:
        coll - the Collection to convert (potentially null or empty)
        Returns:
        the delimited String

      • arrayToDelimitedString

        public static java.lang.String arrayToDelimitedString​(@Nullable
                                                      java.lang.Object[] arr,
                                                      java.lang.String delim)
        Convert a String array into a delimited String (e.g. CSV).

        Useful for toString() implementations.

        Parameters:
        arr - the array to display (potentially null or empty)
        delim - the delimiter to use (typically a ",")
        Returns:
        the delimited String

      • arrayToCommaDelimitedString

        public static java.lang.String arrayToCommaDelimitedString​(@Nullable
                                                           java.lang.Object[] arr)
        Convert a String array into a comma delimited String (i.e., CSV).

        Useful for toString() implementations.

        Parameters:
        arr - the array to display (potentially null or empty)
        Returns:
        the delimited String