Class RegExUtils

java.lang.Object
org.apache.commons.lang3.RegExUtils

public class RegExUtils extends Object
Helpers to process Strings using regular expressions.
Since:
3.8
See Also:
  • Constructor Details

  • Method Details

    • dotAll

      public static Pattern dotAll(String regex)
      Compiles the given regular expression into a pattern with the Pattern.DOTALL flag.
      Parameters:
      regex - The expression to be compiled
      Returns:
      the given regular expression compiled into a pattern with the Pattern.DOTALL flag.
      Since:
      3.13.0
    • dotAllMatcher

      public static Matcher dotAllMatcher(String regex, String text)
      Compiles the given regular expression into a pattern with the Pattern.DOTALL flag, then creates a matcher that will match the given text against this pattern.
      Parameters:
      regex - The expression to be compiled.
      text - The character sequence to be matched.
      Returns:
      A new matcher for this pattern.
      Since:
      3.13.0
    • removeAll

      public static String removeAll(String text, Pattern regex)
      Removes each substring of the text String that matches the given regular expression pattern. This method is a null safe equivalent to:
      • pattern.matcher(text).replaceAll(StringUtils.EMPTY)

      A null reference passed to this method is a no-op.

      
       StringUtils.removeAll(null, *)      = null
       StringUtils.removeAll("any", (Pattern) null)  = "any"
       StringUtils.removeAll("any", Pattern.compile(""))    = "any"
       StringUtils.removeAll("any", Pattern.compile(".*"))  = ""
       StringUtils.removeAll("any", Pattern.compile(".+"))  = ""
       StringUtils.removeAll("abc", Pattern.compile(".?"))  = ""
       StringUtils.removeAll("A<__>\n<__>B", Pattern.compile("<.*>"))      = "A\nB"
       StringUtils.removeAll("A<__>\n<__>B", Pattern.compile("(?s)<.*>"))  = "AB"
       StringUtils.removeAll("A<__>\n<__>B", Pattern.compile("<.*>", Pattern.DOTALL))  = "AB"
       StringUtils.removeAll("ABCabc123abc", Pattern.compile("[a-z]"))     = "ABC123"
       
      Parameters:
      text - text to remove from, may be null
      regex - the regular expression to which this string is to be matched
      Returns:
      the text with any removes processed, null if null String input
      See Also:
    • removeAll

      public static String removeAll(String text, String regex)
      Removes each substring of the text String that matches the given regular expression. This method is a null safe equivalent to:
      • text.replaceAll(regex, StringUtils.EMPTY)
      • Pattern.compile(regex).matcher(text).replaceAll(StringUtils.EMPTY)

      A null reference passed to this method is a no-op.

      Unlike in the removePattern(String, String) method, the Pattern.DOTALL option is NOT automatically added. To use the DOTALL option prepend "(?s)" to the regex. DOTALL is also known as single-line mode in Perl.

      
       StringUtils.removeAll(null, *)      = null
       StringUtils.removeAll("any", (String) null)  = "any"
       StringUtils.removeAll("any", "")    = "any"
       StringUtils.removeAll("any", ".*")  = ""
       StringUtils.removeAll("any", ".+")  = ""
       StringUtils.removeAll("abc", ".?")  = ""
       StringUtils.removeAll("A<__>\n<__>B", "<.*>")      = "A\nB"
       StringUtils.removeAll("A<__>\n<__>B", "(?s)<.*>")  = "AB"
       StringUtils.removeAll("ABCabc123abc", "[a-z]")     = "ABC123"
       
      Parameters:
      text - text to remove from, may be null
      regex - the regular expression to which this string is to be matched
      Returns:
      the text with any removes processed, null if null String input
      Throws:
      PatternSyntaxException - if the regular expression's syntax is invalid
      See Also:
    • removeFirst

      public static String removeFirst(String text, Pattern regex)
      Removes the first substring of the text string that matches the given regular expression pattern. This method is a null safe equivalent to:
      • pattern.matcher(text).replaceFirst(StringUtils.EMPTY)

      A null reference passed to this method is a no-op.

      
       StringUtils.removeFirst(null, *)      = null
       StringUtils.removeFirst("any", (Pattern) null)  = "any"
       StringUtils.removeFirst("any", Pattern.compile(""))    = "any"
       StringUtils.removeFirst("any", Pattern.compile(".*"))  = ""
       StringUtils.removeFirst("any", Pattern.compile(".+"))  = ""
       StringUtils.removeFirst("abc", Pattern.compile(".?"))  = "bc"
       StringUtils.removeFirst("A<__>\n<__>B", Pattern.compile("<.*>"))      = "A\n<__>B"
       StringUtils.removeFirst("A<__>\n<__>B", Pattern.compile("(?s)<.*>"))  = "AB"
       StringUtils.removeFirst("ABCabc123", Pattern.compile("[a-z]"))          = "ABCbc123"
       StringUtils.removeFirst("ABCabc123abc", Pattern.compile("[a-z]+"))      = "ABC123abc"
       
      Parameters:
      text - text to remove from, may be null
      regex - the regular expression pattern to which this string is to be matched
      Returns:
      the text with the first replacement processed, null if null String input
      See Also:
    • removeFirst

      public static String removeFirst(String text, String regex)
      Removes the first substring of the text string that matches the given regular expression. This method is a null safe equivalent to:
      • text.replaceFirst(regex, StringUtils.EMPTY)
      • Pattern.compile(regex).matcher(text).replaceFirst(StringUtils.EMPTY)

      A null reference passed to this method is a no-op.

      The Pattern.DOTALL option is NOT automatically added. To use the DOTALL option prepend "(?s)" to the regex. DOTALL is also known as single-line mode in Perl.

      
       StringUtils.removeFirst(null, *)      = null
       StringUtils.removeFirst("any", (String) null)  = "any"
       StringUtils.removeFirst("any", "")    = "any"
       StringUtils.removeFirst("any", ".*")  = ""
       StringUtils.removeFirst("any", ".+")  = ""
       StringUtils.removeFirst("abc", ".?")  = "bc"
       StringUtils.removeFirst("A<__>\n<__>B", "<.*>")      = "A\n<__>B"
       StringUtils.removeFirst("A<__>\n<__>B", "(?s)<.*>")  = "AB"
       StringUtils.removeFirst("ABCabc123", "[a-z]")          = "ABCbc123"
       StringUtils.removeFirst("ABCabc123abc", "[a-z]+")      = "ABC123abc"
       
      Parameters:
      text - text to remove from, may be null
      regex - the regular expression to which this string is to be matched
      Returns:
      the text with the first replacement processed, null if null String input
      Throws:
      PatternSyntaxException - if the regular expression's syntax is invalid
      See Also:
    • removePattern

      public static String removePattern(String text, String regex)
      Removes each substring of the source String that matches the given regular expression using the DOTALL option. This call is a null safe equivalent to:
      • text.replaceAll(&quot;(?s)&quot; + regex, StringUtils.EMPTY)
      • Pattern.compile(regex, Pattern.DOTALL).matcher(text).replaceAll(StringUtils.EMPTY)

      A null reference passed to this method is a no-op.

      
       StringUtils.removePattern(null, *)       = null
       StringUtils.removePattern("any", (String) null)   = "any"
       StringUtils.removePattern("A<__>\n<__>B", "<.*>")  = "AB"
       StringUtils.removePattern("ABCabc123", "[a-z]")    = "ABC123"
       
      Parameters:
      text - the source string
      regex - the regular expression to which this string is to be matched
      Returns:
      The resulting String
      See Also:
    • replaceAll

      public static String replaceAll(String text, Pattern regex, String replacement)
      Replaces each substring of the text String that matches the given regular expression pattern with the given replacement. This method is a null safe equivalent to:
      • pattern.matcher(text).replaceAll(replacement)

      A null reference passed to this method is a no-op.

      
       StringUtils.replaceAll(null, *, *)       = null
       StringUtils.replaceAll("any", (Pattern) null, *)   = "any"
       StringUtils.replaceAll("any", *, null)   = "any"
       StringUtils.replaceAll("", Pattern.compile(""), "zzz")    = "zzz"
       StringUtils.replaceAll("", Pattern.compile(".*"), "zzz")  = "zzz"
       StringUtils.replaceAll("", Pattern.compile(".+"), "zzz")  = ""
       StringUtils.replaceAll("abc", Pattern.compile(""), "ZZ")  = "ZZaZZbZZcZZ"
       StringUtils.replaceAll("<__>\n<__>", Pattern.compile("<.*>"), "z")                 = "z\nz"
       StringUtils.replaceAll("<__>\n<__>", Pattern.compile("<.*>", Pattern.DOTALL), "z") = "z"
       StringUtils.replaceAll("<__>\n<__>", Pattern.compile("(?s)<.*>"), "z")             = "z"
       StringUtils.replaceAll("ABCabc123", Pattern.compile("[a-z]"), "_")       = "ABC___123"
       StringUtils.replaceAll("ABCabc123", Pattern.compile("[^A-Z0-9]+"), "_")  = "ABC_123"
       StringUtils.replaceAll("ABCabc123", Pattern.compile("[^A-Z0-9]+"), "")   = "ABC123"
       StringUtils.replaceAll("Lorem ipsum  dolor   sit", Pattern.compile("( +)([a-z]+)"), "_$2")  = "Lorem_ipsum_dolor_sit"
       
      Parameters:
      text - text to search and replace in, may be null
      regex - the regular expression pattern to which this string is to be matched
      replacement - the string to be substituted for each match
      Returns:
      the text with any replacements processed, null if null String input
      See Also:
    • replaceAll

      public static String replaceAll(String text, String regex, String replacement)
      Replaces each substring of the text String that matches the given regular expression with the given replacement. This method is a null safe equivalent to:
      • text.replaceAll(regex, replacement)
      • Pattern.compile(regex).matcher(text).replaceAll(replacement)

      A null reference passed to this method is a no-op.

      Unlike in the replacePattern(String, String, String) method, the Pattern.DOTALL option is NOT automatically added. To use the DOTALL option prepend "(?s)" to the regex. DOTALL is also known as single-line mode in Perl.

      
       StringUtils.replaceAll(null, *, *)       = null
       StringUtils.replaceAll("any", (String) null, *)   = "any"
       StringUtils.replaceAll("any", *, null)   = "any"
       StringUtils.replaceAll("", "", "zzz")    = "zzz"
       StringUtils.replaceAll("", ".*", "zzz")  = "zzz"
       StringUtils.replaceAll("", ".+", "zzz")  = ""
       StringUtils.replaceAll("abc", "", "ZZ")  = "ZZaZZbZZcZZ"
       StringUtils.replaceAll("<__>\n<__>", "<.*>", "z")      = "z\nz"
       StringUtils.replaceAll("<__>\n<__>", "(?s)<.*>", "z")  = "z"
       StringUtils.replaceAll("ABCabc123", "[a-z]", "_")       = "ABC___123"
       StringUtils.replaceAll("ABCabc123", "[^A-Z0-9]+", "_")  = "ABC_123"
       StringUtils.replaceAll("ABCabc123", "[^A-Z0-9]+", "")   = "ABC123"
       StringUtils.replaceAll("Lorem ipsum  dolor   sit", "( +)([a-z]+)", "_$2")  = "Lorem_ipsum_dolor_sit"
       
      Parameters:
      text - text to search and replace in, may be null
      regex - the regular expression to which this string is to be matched
      replacement - the string to be substituted for each match
      Returns:
      the text with any replacements processed, null if null String input
      Throws:
      PatternSyntaxException - if the regular expression's syntax is invalid
      See Also:
    • replaceFirst

      public static String replaceFirst(String text, Pattern regex, String replacement)
      Replaces the first substring of the text string that matches the given regular expression pattern with the given replacement. This method is a null safe equivalent to:
      • pattern.matcher(text).replaceFirst(replacement)

      A null reference passed to this method is a no-op.

      
       StringUtils.replaceFirst(null, *, *)       = null
       StringUtils.replaceFirst("any", (Pattern) null, *)   = "any"
       StringUtils.replaceFirst("any", *, null)   = "any"
       StringUtils.replaceFirst("", Pattern.compile(""), "zzz")    = "zzz"
       StringUtils.replaceFirst("", Pattern.compile(".*"), "zzz")  = "zzz"
       StringUtils.replaceFirst("", Pattern.compile(".+"), "zzz")  = ""
       StringUtils.replaceFirst("abc", Pattern.compile(""), "ZZ")  = "ZZabc"
       StringUtils.replaceFirst("<__>\n<__>", Pattern.compile("<.*>"), "z")      = "z\n<__>"
       StringUtils.replaceFirst("<__>\n<__>", Pattern.compile("(?s)<.*>"), "z")  = "z"
       StringUtils.replaceFirst("ABCabc123", Pattern.compile("[a-z]"), "_")          = "ABC_bc123"
       StringUtils.replaceFirst("ABCabc123abc", Pattern.compile("[^A-Z0-9]+"), "_")  = "ABC_123abc"
       StringUtils.replaceFirst("ABCabc123abc", Pattern.compile("[^A-Z0-9]+"), "")   = "ABC123abc"
       StringUtils.replaceFirst("Lorem ipsum  dolor   sit", Pattern.compile("( +)([a-z]+)"), "_$2")  = "Lorem_ipsum  dolor   sit"
       
      Parameters:
      text - text to search and replace in, may be null
      regex - the regular expression pattern to which this string is to be matched
      replacement - the string to be substituted for the first match
      Returns:
      the text with the first replacement processed, null if null String input
      See Also:
    • replaceFirst

      public static String replaceFirst(String text, String regex, String replacement)
      Replaces the first substring of the text string that matches the given regular expression with the given replacement. This method is a null safe equivalent to:
      • text.replaceFirst(regex, replacement)
      • Pattern.compile(regex).matcher(text).replaceFirst(replacement)

      A null reference passed to this method is a no-op.

      The Pattern.DOTALL option is NOT automatically added. To use the DOTALL option prepend "(?s)" to the regex. DOTALL is also known as single-line mode in Perl.

      
       StringUtils.replaceFirst(null, *, *)       = null
       StringUtils.replaceFirst("any", (String) null, *)   = "any"
       StringUtils.replaceFirst("any", *, null)   = "any"
       StringUtils.replaceFirst("", "", "zzz")    = "zzz"
       StringUtils.replaceFirst("", ".*", "zzz")  = "zzz"
       StringUtils.replaceFirst("", ".+", "zzz")  = ""
       StringUtils.replaceFirst("abc", "", "ZZ")  = "ZZabc"
       StringUtils.replaceFirst("<__>\n<__>", "<.*>", "z")      = "z\n<__>"
       StringUtils.replaceFirst("<__>\n<__>", "(?s)<.*>", "z")  = "z"
       StringUtils.replaceFirst("ABCabc123", "[a-z]", "_")          = "ABC_bc123"
       StringUtils.replaceFirst("ABCabc123abc", "[^A-Z0-9]+", "_")  = "ABC_123abc"
       StringUtils.replaceFirst("ABCabc123abc", "[^A-Z0-9]+", "")   = "ABC123abc"
       StringUtils.replaceFirst("Lorem ipsum  dolor   sit", "( +)([a-z]+)", "_$2")  = "Lorem_ipsum  dolor   sit"
       
      Parameters:
      text - text to search and replace in, may be null
      regex - the regular expression to which this string is to be matched
      replacement - the string to be substituted for the first match
      Returns:
      the text with the first replacement processed, null if null String input
      Throws:
      PatternSyntaxException - if the regular expression's syntax is invalid
      See Also:
    • replacePattern

      public static String replacePattern(String text, String regex, String replacement)
      Replaces each substring of the source String that matches the given regular expression with the given replacement using the Pattern.DOTALL option. DOTALL is also known as single-line mode in Perl. This call is a null safe equivalent to:
      • text.replaceAll(&quot;(?s)&quot; + regex, replacement)
      • Pattern.compile(regex, Pattern.DOTALL).matcher(text).replaceAll(replacement)

      A null reference passed to this method is a no-op.

      
       StringUtils.replacePattern(null, *, *)       = null
       StringUtils.replacePattern("any", (String) null, *)   = "any"
       StringUtils.replacePattern("any", *, null)   = "any"
       StringUtils.replacePattern("", "", "zzz")    = "zzz"
       StringUtils.replacePattern("", ".*", "zzz")  = "zzz"
       StringUtils.replacePattern("", ".+", "zzz")  = ""
       StringUtils.replacePattern("<__>\n<__>", "<.*>", "z")       = "z"
       StringUtils.replacePattern("ABCabc123", "[a-z]", "_")       = "ABC___123"
       StringUtils.replacePattern("ABCabc123", "[^A-Z0-9]+", "_")  = "ABC_123"
       StringUtils.replacePattern("ABCabc123", "[^A-Z0-9]+", "")   = "ABC123"
       StringUtils.replacePattern("Lorem ipsum  dolor   sit", "( +)([a-z]+)", "_$2")  = "Lorem_ipsum_dolor_sit"
       
      Parameters:
      text - the source string
      regex - the regular expression to which this string is to be matched
      replacement - the string to be substituted for each match
      Returns:
      The resulting String
      See Also: