Package co.aikar.commands.apachecommonslang

Class ApacheCommonsLangUtil

java.lang.Object
co.aikar.commands.apachecommonslang.ApacheCommonsLangUtil
public class ApacheCommonsLangUtil extends Object
Select methods copied from Apache Commons to avoid importing entire lib No changes to logic

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final String
    EMPTY
    The empty String "".
    static final int
    INDEX_NOT_FOUND
    The index value when an element is not found in a list or array: -1.

  • Constructor Summary

    Constructors
    Constructor
    Description
    ApacheCommonsLangUtil()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static <T> T[]
    addAll(T[] array1, T... array2)
    Adds all the elements of the given arrays into a new array.
    static String
    capitalize(String str)
    Capitalizes all the whitespace separated words in a String.
    static String
    capitalize(String str, char... delimiters)
    Capitalizes all the delimiter separated words in a String.
    static String
    capitalizeFully(String str)
    Converts all the whitespace separated words in a String into capitalized words, that is each word is made up of a titlecase character and then a series of lowercase characters.
    static String
    capitalizeFully(String str, char... delimiters)
    Converts all the delimiter separated words in a String into capitalized words, that is each word is made up of a titlecase character and then a series of lowercase characters.
    static <T> T[]
    clone(T[] array)
    Shallow clones an array returning a typecast result and handling null.
    static int
    indexOf(Object[] array, Object objectToFind)
    Finds the index of the given object in the array.
    static int
    indexOf(Object[] array, Object objectToFind, int startIndex)
    Finds the index of the given object in the array starting at the given index.
    static boolean
    isDelimiter(char ch, char[] delimiters)
    Is the character a delimiter.
    static boolean
    isNumeric(CharSequence cs)
    Checks if the CharSequence contains only Unicode digits.
    static String
    join(byte[] array, char separator)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(byte[] array, char separator, int startIndex, int endIndex)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(char[] array, char separator)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(char[] array, char separator, int startIndex, int endIndex)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(double[] array, char separator)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(double[] array, char separator, int startIndex, int endIndex)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(float[] array, char separator)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(float[] array, char separator, int startIndex, int endIndex)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(int[] array, char separator)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(int[] array, char separator, int startIndex, int endIndex)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(long[] array, char separator)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(long[] array, char separator, int startIndex, int endIndex)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(short[] array, char separator)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(short[] array, char separator, int startIndex, int endIndex)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(Iterable<?> iterable, char separator)
    Joins the elements of the provided Iterable into a single String containing the provided elements.
    static String
    join(Iterable<?> iterable, String separator)
    Joins the elements of the provided Iterable into a single String containing the provided elements.
    static String
    join(Object[] array, char separator)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(Object[] array, char separator, int startIndex, int endIndex)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(Object[] array, String separator)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(Object[] array, String separator, int startIndex, int endIndex)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static String
    join(Iterator<?> iterator, char separator)
    Joins the elements of the provided Iterator into a single String containing the provided elements.
    static String
    join(Iterator<?> iterator, String separator)
    Joins the elements of the provided Iterator into a single String containing the provided elements.
    static <T> String
    join(T... elements)
    Joins the elements of the provided array into a single String containing the provided list of elements.
    static boolean
    startsWith(CharSequence str, CharSequence prefix)
    Check if a CharSequence starts with a specified prefix.
    static boolean
    startsWithIgnoreCase(CharSequence str, CharSequence prefix)
    Case insensitive check if a CharSequence starts with a specified prefix.

    Methods inherited from class java.lang.Object

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

  • Field Details

    • EMPTY

      public static final String EMPTY
      The empty String "".
      Since:
      2.0
      See Also:

    • INDEX_NOT_FOUND

      public static final int INDEX_NOT_FOUND
      The index value when an element is not found in a list or array: -1. This value is returned by methods in this class and can also be used in comparisons with values returned by various method from List.
      See Also:

  • Constructor Details

  • Method Details

    • clone

      public static <T> T[] clone(T[] array)

      Shallow clones an array returning a typecast result and handling null.

      The objects in the array are not cloned, thus there is no special handling for multi-dimensional arrays.

      This method returns null for a null input array.

      Type Parameters:
      T - the component type of the array
      Parameters:
      array - the array to shallow clone, may be null
      Returns:
      the cloned array, null if null input

    • addAll

      public static <T> T[] addAll(T[] array1, T... array2)

      Adds all the elements of the given arrays into a new array.

      The new array contains all of the element of array1 followed by all of the elements array2. When an array is returned, it is always a new array. 

       ArrayUtils.addAll(null, null)     = null
 ArrayUtils.addAll(array1, null)   = cloned copy of array1
 ArrayUtils.addAll(null, array2)   = cloned copy of array2
 ArrayUtils.addAll([], [])         = []
 ArrayUtils.addAll([null], [null]) = [null, null]
 ArrayUtils.addAll(["a", "b", "c"], ["1", "2", "3"]) = ["a", "b", "c", "1", "2", "3"]
      Type Parameters:
      T - the component type of the array
      Parameters:
      array1 - the first array whose elements are added to the new array, may be null
      array2 - the second array whose elements are added to the new array, may be null
      Returns:
      The new array, null if both arrays are null. The type of the new array is the type of the first array, unless the first array is null, in which case the type is the same as the second array.
      Throws:
      IllegalArgumentException - if the array types are incompatible
      Since:
      2.1

    • capitalizeFully

      public static String capitalizeFully(String str)

      Converts all the whitespace separated words in a String into capitalized words, that is each word is made up of a titlecase character and then a series of lowercase characters.

      Whitespace is defined by Character.isWhitespace(char). A null input String returns null. Capitalization uses the Unicode title case, normally equivalent to upper case.

       WordUtils.capitalizeFully(null)        = null
 WordUtils.capitalizeFully("")          = ""
 WordUtils.capitalizeFully("i am FINE") = "I Am Fine"
      Parameters:
      str - the String to capitalize, may be null
      Returns:
      capitalized String, null if null String input

    • capitalizeFully

      public static String capitalizeFully(String str, char... delimiters)

      Converts all the delimiter separated words in a String into capitalized words, that is each word is made up of a titlecase character and then a series of lowercase characters.

      The delimiters represent a set of characters understood to separate words. The first string character and the first non-delimiter character after a delimiter will be capitalized.

      A null input String returns null. Capitalization uses the Unicode title case, normally equivalent to upper case.

       WordUtils.capitalizeFully(null, *)            = null
 WordUtils.capitalizeFully("", *)              = ""
 WordUtils.capitalizeFully(*, null)            = *
 WordUtils.capitalizeFully(*, new char[0])     = *
 WordUtils.capitalizeFully("i aM.fine", {'.'}) = "I am.Fine"
      Parameters:
      str - the String to capitalize, may be null
      delimiters - set of characters to determine capitalization, null means whitespace
      Returns:
      capitalized String, null if null String input
      Since:
      2.1

    • capitalize

      public static String capitalize(String str)

      Capitalizes all the whitespace separated words in a String. Only the first character of each word is changed. To convert the rest of each word to lowercase at the same time, use capitalizeFully(String).

      Whitespace is defined by Character.isWhitespace(char). A null input String returns null. Capitalization uses the Unicode title case, normally equivalent to upper case.

       WordUtils.capitalize(null)        = null
 WordUtils.capitalize("")          = ""
 WordUtils.capitalize("i am FINE") = "I Am FINE"
      Parameters:
      str - the String to capitalize, may be null
      Returns:
      capitalized String, null if null String input
      See Also:

    • capitalize

      public static String capitalize(String str, char... delimiters)

      Capitalizes all the delimiter separated words in a String. Only the first character of each word is changed. To convert the rest of each word to lowercase at the same time, use capitalizeFully(String, char[]).

      The delimiters represent a set of characters understood to separate words. The first string character and the first non-delimiter character after a delimiter will be capitalized.

      A null input String returns null. Capitalization uses the Unicode title case, normally equivalent to upper case.

       WordUtils.capitalize(null, *)            = null
 WordUtils.capitalize("", *)              = ""
 WordUtils.capitalize(*, new char[0])     = *
 WordUtils.capitalize("i am fine", null)  = "I Am Fine"
 WordUtils.capitalize("i aM.fine", {'.'}) = "I aM.Fine"
      Parameters:
      str - the String to capitalize, may be null
      delimiters - set of characters to determine capitalization, null means whitespace
      Returns:
      capitalized String, null if null String input
      Since:
      2.1
      See Also:

    • isDelimiter

      public static boolean isDelimiter(char ch, char[] delimiters)
      Is the character a delimiter.
      Parameters:
      ch - the character to check
      delimiters - the delimiters
      Returns:
      true if it is a delimiter

    • join

      @SafeVarargs public static <T> String join(T... elements)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No separator is added to the joined String. Null objects or empty strings within the array are represented by empty strings.

       StringUtils.join(null)            = null
 StringUtils.join([])              = ""
 StringUtils.join([null])          = ""
 StringUtils.join(["a", "b", "c"]) = "abc"
 StringUtils.join([null, "", "a"]) = "a"
      Type Parameters:
      T - the specific type of values to join together
      Parameters:
      elements - the values to join together, may be null
      Returns:
      the joined String, null if null array input
      Since:
      2.0, 3.0 Changed signature to use varargs

    • join

      public static String join(Object[] array, char separator)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings.

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join(["a", "b", "c"], ';')  = "a;b;c"
 StringUtils.join(["a", "b", "c"], null) = "abc"
 StringUtils.join([null, "", "a"], ';')  = ";;a"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      Returns:
      the joined String, null if null array input
      Since:
      2.0

    • join

      public static String join(long[] array, char separator)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(int[] array, char separator)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(short[] array, char separator)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(byte[] array, char separator)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(char[] array, char separator)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(float[] array, char separator)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(double[] array, char separator)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(Object[] array, char separator, int startIndex, int endIndex)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings.

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join(["a", "b", "c"], ';')  = "a;b;c"
 StringUtils.join(["a", "b", "c"], null) = "abc"
 StringUtils.join([null, "", "a"], ';')  = ";;a"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      startIndex - the first index to start joining from. It is an error to pass in an end index past the end of the array
      endIndex - the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the array
      Returns:
      the joined String, null if null array input
      Since:
      2.0

    • join

      public static String join(long[] array, char separator, int startIndex, int endIndex)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      startIndex - the first index to start joining from. It is an error to pass in an end index past the end of the array
      endIndex - the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the array
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(int[] array, char separator, int startIndex, int endIndex)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      startIndex - the first index to start joining from. It is an error to pass in an end index past the end of the array
      endIndex - the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the array
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(byte[] array, char separator, int startIndex, int endIndex)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      startIndex - the first index to start joining from. It is an error to pass in an end index past the end of the array
      endIndex - the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the array
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(short[] array, char separator, int startIndex, int endIndex)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      startIndex - the first index to start joining from. It is an error to pass in an end index past the end of the array
      endIndex - the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the array
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(char[] array, char separator, int startIndex, int endIndex)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      startIndex - the first index to start joining from. It is an error to pass in an end index past the end of the array
      endIndex - the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the array
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(double[] array, char separator, int startIndex, int endIndex)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      startIndex - the first index to start joining from. It is an error to pass in an end index past the end of the array
      endIndex - the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the array
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(float[] array, char separator, int startIndex, int endIndex)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. 

       StringUtils.join(null, *)               = null
 StringUtils.join([], *)                 = ""
 StringUtils.join([null], *)             = ""
 StringUtils.join([1, 2, 3], ';')  = "1;2;3"
 StringUtils.join([1, 2, 3], null) = "123"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use
      startIndex - the first index to start joining from. It is an error to pass in an end index past the end of the array
      endIndex - the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the array
      Returns:
      the joined String, null if null array input
      Since:
      3.2

    • join

      public static String join(Object[] array, String separator)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. A null separator is the same as an empty String (""). Null objects or empty strings within the array are represented by empty strings.

       StringUtils.join(null, *)                = null
 StringUtils.join([], *)                  = ""
 StringUtils.join([null], *)              = ""
 StringUtils.join(["a", "b", "c"], "--")  = "a--b--c"
 StringUtils.join(["a", "b", "c"], null)  = "abc"
 StringUtils.join(["a", "b", "c"], "")    = "abc"
 StringUtils.join([null, "", "a"], ',')   = ",,a"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use, null treated as ""
      Returns:
      the joined String, null if null array input

    • join

      public static String join(Object[] array, String separator, int startIndex, int endIndex)

      Joins the elements of the provided array into a single String containing the provided list of elements.

      No delimiter is added before or after the list. A null separator is the same as an empty String (""). Null objects or empty strings within the array are represented by empty strings.

       StringUtils.join(null, *, *, *)                = null
 StringUtils.join([], *, *, *)                  = ""
 StringUtils.join([null], *, *, *)              = ""
 StringUtils.join(["a", "b", "c"], "--", 0, 3)  = "a--b--c"
 StringUtils.join(["a", "b", "c"], "--", 1, 3)  = "b--c"
 StringUtils.join(["a", "b", "c"], "--", 2, 3)  = "c"
 StringUtils.join(["a", "b", "c"], "--", 2, 2)  = ""
 StringUtils.join(["a", "b", "c"], null, 0, 3)  = "abc"
 StringUtils.join(["a", "b", "c"], "", 0, 3)    = "abc"
 StringUtils.join([null, "", "a"], ',', 0, 3)   = ",,a"
      Parameters:
      array - the array of values to join together, may be null
      separator - the separator character to use, null treated as ""
      startIndex - the first index to start joining from.
      endIndex - the index to stop joining from (exclusive).
      Returns:
      the joined String, null if null array input; or the empty string if endIndex - startIndex <= 0. The number of joined entries is given by endIndex - startIndex
      Throws:
      ArrayIndexOutOfBoundsException - ife
      startIndex < 0 or
      startIndex >= array.length() or
      endIndex < 0 or
      endIndex > array.length()

    • join

      public static String join(Iterator<?> iterator, char separator)

      Joins the elements of the provided Iterator into a single String containing the provided elements.

      No delimiter is added before or after the list. Null objects or empty strings within the iteration are represented by empty strings.

      See the examples here: join(Object[],char).

      Parameters:
      iterator - the Iterator of values to join together, may be null
      separator - the separator character to use
      Returns:
      the joined String, null if null iterator input
      Since:
      2.0

    • join

      public static String join(Iterator<?> iterator, String separator)

      Joins the elements of the provided Iterator into a single String containing the provided elements.

      No delimiter is added before or after the list. A null separator is the same as an empty String ("").

      See the examples here: join(Object[],String).

      Parameters:
      iterator - the Iterator of values to join together, may be null
      separator - the separator character to use, null treated as ""
      Returns:
      the joined String, null if null iterator input

    • join

      public static String join(Iterable<?> iterable, char separator)

      Joins the elements of the provided Iterable into a single String containing the provided elements.

      No delimiter is added before or after the list. Null objects or empty strings within the iteration are represented by empty strings.

      See the examples here: join(Object[],char).

      Parameters:
      iterable - the Iterable providing the values to join together, may be null
      separator - the separator character to use
      Returns:
      the joined String, null if null iterator input
      Since:
      2.3

    • join

      public static String join(Iterable<?> iterable, String separator)

      Joins the elements of the provided Iterable into a single String containing the provided elements.

      No delimiter is added before or after the list. A null separator is the same as an empty String ("").

      See the examples here: join(Object[],String).

      Parameters:
      iterable - the Iterable providing the values to join together, may be null
      separator - the separator character to use, null treated as ""
      Returns:
      the joined String, null if null iterator input
      Since:
      2.3

    • isNumeric

      public static boolean isNumeric(CharSequence cs)

      Checks if the CharSequence contains only Unicode digits. A decimal point is not a Unicode digit and returns false.

      null will return false. An empty CharSequence (length()=0) will return false.

      Note that the method does not allow for a leading sign, either positive or negative. Also, if a String passes the numeric test, it may still generate a NumberFormatException when parsed by Integer.parseInt or Long.parseLong, e.g. if the value is outside the range for int or long respectively.

       StringUtils.isNumeric(null)   = false
 StringUtils.isNumeric("")     = false
 StringUtils.isNumeric("  ")   = false
 StringUtils.isNumeric("123")  = true
 StringUtils.isNumeric("१२३")  = true
 StringUtils.isNumeric("12 3") = false
 StringUtils.isNumeric("ab2c") = false
 StringUtils.isNumeric("12-3") = false
 StringUtils.isNumeric("12.3") = false
 StringUtils.isNumeric("-123") = false
 StringUtils.isNumeric("+123") = false
      Parameters:
      cs - the CharSequence to check, may be null
      Returns:
      true if only contains digits, and is non-null
      Since:
      3.0 Changed signature from isNumeric(String) to isNumeric(CharSequence), 3.0 Changed "" to return false and not true

    • startsWith

      public static boolean startsWith(CharSequence str, CharSequence prefix)

      Check if a CharSequence starts with a specified prefix.

      nulls are handled without exceptions. Two null references are considered to be equal. The comparison is case sensitive.

       StringUtils.startsWith(null, null)      = true
 StringUtils.startsWith(null, "abc")     = false
 StringUtils.startsWith("abcdef", null)  = false
 StringUtils.startsWith("abcdef", "abc") = true
 StringUtils.startsWith("ABCDEF", "abc") = false
      Parameters:
      str - the CharSequence to check, may be null
      prefix - the prefix to find, may be null
      Returns:
      true if the CharSequence starts with the prefix, case sensitive, or both null
      Since:
      2.4, 3.0 Changed signature from startsWith(String, String) to startsWith(CharSequence, CharSequence)
      See Also:

    • startsWithIgnoreCase

      public static boolean startsWithIgnoreCase(CharSequence str, CharSequence prefix)

      Case insensitive check if a CharSequence starts with a specified prefix.

      nulls are handled without exceptions. Two null references are considered to be equal. The comparison is case insensitive.

       StringUtils.startsWithIgnoreCase(null, null)      = true
 StringUtils.startsWithIgnoreCase(null, "abc")     = false
 StringUtils.startsWithIgnoreCase("abcdef", null)  = false
 StringUtils.startsWithIgnoreCase("abcdef", "abc") = true
 StringUtils.startsWithIgnoreCase("ABCDEF", "abc") = true
      Parameters:
      str - the CharSequence to check, may be null
      prefix - the prefix to find, may be null
      Returns:
      true if the CharSequence starts with the prefix, case insensitive, or both null
      Since:
      2.4, 3.0 Changed signature from startsWithIgnoreCase(String, String) to startsWithIgnoreCase(CharSequence, CharSequence)
      See Also:

    • indexOf

      public static int indexOf(Object[] array, Object objectToFind)

      Finds the index of the given object in the array.

      This method returns INDEX_NOT_FOUND (-1) for a null input array.

      Parameters:
      array - the array to search through for the object, may be null
      objectToFind - the object to find, may be null
      Returns:
      the index of the object within the array, INDEX_NOT_FOUND (-1) if not found or null array input

    • indexOf

      public static int indexOf(Object[] array, Object objectToFind, int startIndex)

      Finds the index of the given object in the array starting at the given index.

      This method returns INDEX_NOT_FOUND (-1) for a null input array.

      A negative startIndex is treated as zero. A startIndex larger than the array length will return INDEX_NOT_FOUND (-1).

      Parameters:
      array - the array to search through for the object, may be null
      objectToFind - the object to find, may be null
      startIndex - the index to start searching at
      Returns:
      the index of the object within the array starting at the index, INDEX_NOT_FOUND (-1) if not found or null array input