Package org.apache.camel.util

Class StringHelper

java.lang.Object
org.apache.camel.util.StringHelper
public final class StringHelper extends Object
Helper methods for working with Strings.

  • Method Details

    • sanitize

      public static String sanitize(String s)
      Ensures that s is friendly for a URL or file system.
      Parameters:
      s - String to be sanitized.
      Returns:
      sanitized version of s.
      Throws:
      NullPointerException - if s is null.

    • removeCRLF

      public static String removeCRLF(String s)
      Remove carriage return and line feeds from a String, replacing them with an empty String.
      Parameters:
      s - String to be sanitized of carriage return / line feed characters
      Returns:
      sanitized version of s.
      Throws:
      NullPointerException - if s is null.

    • countChar

      public static int countChar(String s, char ch)
      Counts the number of times the given char is in the string
      Parameters:
      s - the string
      ch - the char
      Returns:
      number of times char is located in the string

    • countChar

      public static int countChar(String s, char ch, int end)
      Counts the number of times the given char is in the string
      Parameters:
      s - the string
      ch - the char
      end - end index
      Returns:
      number of times char is located in the string

    • limitLength

      public static String limitLength(String s, int maxLength)
      Limits the length of a string
      Parameters:
      s - the string
      maxLength - the maximum length of the returned string
      Returns:
      s if the length of s is less than maxLength or the first maxLength characters of s

    • removeQuotes

      public static String removeQuotes(String s)
      Removes all quotes (single and double) from the string
      Parameters:
      s - the string
      Returns:
      the string without quotes (single and double)

    • removeLeadingAndEndingQuotes

      public static String removeLeadingAndEndingQuotes(String s)
      Removes all leading and ending quotes (single and double) from the string
      Parameters:
      s - the string
      Returns:
      the string without leading and ending quotes (single and double)

    • isQuoted

      public static boolean isQuoted(String s)
      Whether the string starts and ends with either single or double quotes.
      Parameters:
      s - the string
      Returns:
      true if the string starts and ends with either single or double quotes.

    • isSingleQuoted

      public static boolean isSingleQuoted(String s)
      Whether the string starts and ends with single quotes.
      Parameters:
      s - the string
      Returns:
      true if the string starts and ends with single quotes.

    • isDoubleQuoted

      public static boolean isDoubleQuoted(String s)
      Whether the string starts and ends with double quotes.
      Parameters:
      s - the string
      Returns:
      true if the string starts and ends with double quotes.

    • xmlEncode

      public static String xmlEncode(String text)
      Encodes the text into safe XML by replacing < > and & with XML tokens
      Parameters:
      text - the text
      Returns:
      the encoded text

    • hasUpperCase

      public static boolean hasUpperCase(String text)
      Determines if the string has at least one letter in upper case
      Parameters:
      text - the text
      Returns:
      true if at least one letter is upper case, false otherwise

    • isClassName

      public static boolean isClassName(String text)
      Determines if the string is a fully qualified class name

    • hasStartToken

      public static boolean hasStartToken(String expression, String language)
      Does the expression have the language start token?
      Parameters:
      expression - the expression
      language - the name of the language, such as simple
      Returns:
      true if the expression contains the start token, false otherwise

    • replaceFirst

      public static String replaceFirst(String input, String from, String to)
      Replaces the first from token in the given input string.

      This implementation is not recursive, not does it check for tokens in the replacement string.

      Parameters:
      input - the input string
      from - the from string, must not be null or empty
      to - the replacement string, must not be empty
      Returns:
      the replaced string, or the input string if no replacement was needed
      Throws:
      IllegalArgumentException - if the input arguments is invalid

    • toJson

      public static String toJson(String name, String value, boolean isMap)
      Creates a json tuple with the given name/value pair.
      Parameters:
      name - the name
      value - the value
      isMap - whether the tuple should be map
      Returns:
      the json

    • notEmpty

      public static String notEmpty(String value, String name)
      Asserts whether the string is not empty.
      Parameters:
      value - the string to test
      name - the key that resolved the value
      Returns:
      the passed value as is
      Throws:
      IllegalArgumentException - is thrown if assertion fails

    • notEmpty

      public static String notEmpty(String value, String name, Object on)
      Asserts whether the string is not empty.
      Parameters:
      value - the string to test
      on - additional description to indicate where this problem occurred (appended as toString())
      name - the key that resolved the value
      Returns:
      the passed value as is
      Throws:
      IllegalArgumentException - is thrown if assertion fails

    • splitOnCharacter

      public static String[] splitOnCharacter(String value, String needle, int count)

    • splitOnCharacterAsIterator

      public static Iterator<String> splitOnCharacterAsIterator(String value, char needle, int count)

    • splitOnCharacterAsList

      public static List<String> splitOnCharacterAsList(String value, char needle, int count)

    • removeStartingCharacters

      public static String removeStartingCharacters(String text, char ch)
      Removes any starting characters on the given text which match the given character
      Parameters:
      text - the string
      ch - the initial characters to remove
      Returns:
      either the original string or the new substring

    • capitalize

      public static String capitalize(String text)
      Capitalize the string (upper case first character)
      Parameters:
      text - the string
      Returns:
      the string capitalized (upper case first character)

    • capitalize

      public static String capitalize(String text, boolean dashToCamelCase)
      Capitalize the string (upper case first character)
      Parameters:
      text - the string
      dashToCamelCase - whether to also convert dash format into camel case (hello-great-world -> helloGreatWorld)
      Returns:
      the string capitalized (upper case first character)

    • dashToCamelCase

      public static String dashToCamelCase(String text)
      Converts the string from dash format into camel case (hello-great-world -> helloGreatWorld)
      Parameters:
      text - the string
      Returns:
      the string camel cased

    • after

      public static String after(String text, String after)
      Returns the string after the given token
      Parameters:
      text - the text
      after - the token
      Returns:
      the text after the token, or null if text does not contain the token

    • after

      public static String after(String text, String after, String defaultValue)
      Returns the string after the given token, or the default value
      Parameters:
      text - the text
      after - the token
      defaultValue - the value to return if text does not contain the token
      Returns:
      the text after the token, or the supplied defaultValue if text does not contain the token

    • after

      public static <T> Optional<T> after(String text, String after, Function<String,T> mapper)
      Returns an object after the given token
      Parameters:
      text - the text
      after - the token
      mapper - a mapping function to convert the string after the token to type T
      Returns:
      an Optional describing the result of applying a mapping function to the text after the token.

    • afterLast

      public static String afterLast(String text, String after)
      Returns the string after the the last occurrence of the given token
      Parameters:
      text - the text
      after - the token
      Returns:
      the text after the token, or null if text does not contain the token

    • afterLast

      public static String afterLast(String text, String after, String defaultValue)
      Returns the string after the the last occurrence of the given token, or the default value
      Parameters:
      text - the text
      after - the token
      defaultValue - the value to return if text does not contain the token
      Returns:
      the text after the token, or the supplied defaultValue if text does not contain the token

    • before

      public static String before(String text, String before)
      Returns the string before the given token
      Parameters:
      text - the text
      before - the token
      Returns:
      the text before the token, or null if text does not contain the token

    • before

      public static String before(String text, String before, String defaultValue)
      Returns the string before the given token, or the default value
      Parameters:
      text - the text
      before - the token
      defaultValue - the value to return if text does not contain the token
      Returns:
      the text before the token, or the supplied defaultValue if text does not contain the token

    • before

      public static <T> Optional<T> before(String text, String before, Function<String,T> mapper)
      Returns an object before the given token
      Parameters:
      text - the text
      before - the token
      mapper - a mapping function to convert the string before the token to type T
      Returns:
      an Optional describing the result of applying a mapping function to the text before the token.

    • beforeLast

      public static String beforeLast(String text, String before)
      Returns the string before the last occurrence of the given token
      Parameters:
      text - the text
      before - the token
      Returns:
      the text before the token, or null if text does not contain the token

    • beforeLast

      public static String beforeLast(String text, String before, String defaultValue)
      Returns the string before the last occurrence of the given token, or the default value
      Parameters:
      text - the text
      before - the token
      defaultValue - the value to return if text does not contain the token
      Returns:
      the text before the token, or the supplied defaultValue if text does not contain the token

    • between

      public static String between(String text, String after, String before)
      Returns the string between the given tokens
      Parameters:
      text - the text
      after - the before token
      before - the after token
      Returns:
      the text between the tokens, or null if text does not contain the tokens

    • between

      public static <T> Optional<T> between(String text, String after, String before, Function<String,T> mapper)
      Returns an object between the given token
      Parameters:
      text - the text
      after - the before token
      before - the after token
      mapper - a mapping function to convert the string between the token to type T
      Returns:
      an Optional describing the result of applying a mapping function to the text between the token.

    • betweenOuterPair

      public static String betweenOuterPair(String text, char before, char after)
      Returns the string between the most outer pair of tokens

      The number of token pairs must be evenly, eg there must be same number of before and after tokens, otherwise null is returned

      This implementation skips matching when the text is either single or double quoted. For example: ${body.matches("foo('bar')") Will not match the parenthesis from the quoted text.

      Parameters:
      text - the text
      after - the before token
      before - the after token
      Returns:
      the text between the outer most tokens, or null if text does not contain the tokens

    • betweenOuterPair

      public static <T> Optional<T> betweenOuterPair(String text, char before, char after, Function<String,T> mapper)
      Returns an object between the most outer pair of tokens
      Parameters:
      text - the text
      after - the before token
      before - the after token
      mapper - a mapping function to convert the string between the most outer pair of tokens to type T
      Returns:
      an Optional describing the result of applying a mapping function to the text between the most outer pair of tokens.

    • isJavaIdentifier

      public static boolean isJavaIdentifier(String name)
      Returns true if the given name is a valid java identifier

    • normalizeClassName

      public static String normalizeClassName(String name)
      Cleans the string to a pure Java identifier so we can use it for loading class names.

      Especially from Spring DSL people can have \n \t or other characters that otherwise would result in ClassNotFoundException

      Parameters:
      name - the class name
      Returns:
      normalized classname that can be load by a class loader.

    • changedLines

      public static List<Integer> changedLines(String oldText, String newText)
      Compares old and new text content and report back which lines are changed
      Parameters:
      oldText - the old text
      newText - the new text
      Returns:
      a list of line numbers that are changed in the new text

    • trimToNull

      public static String trimToNull(String given)
      Removes the leading and trailing whitespace and if the resulting string is empty returns null. Examples:

      Examples: 

       trimToNull("abc") -> "abc"
 trimToNull(" abc") -> "abc"
 trimToNull(" abc ") -> "abc"
 trimToNull(" ") -> null
 trimToNull("") -> null

    • containsIgnoreCase

      public static boolean containsIgnoreCase(String src, String what)
      Checks if the src string contains what
      Parameters:
      src - is the source string to be checked
      what - is the string which will be looked up in the src argument
      Returns:
      true/false

    • humanReadableBytes

      public static String humanReadableBytes(Locale locale, long bytes)
      Outputs the bytes in human readable format in units of KB,MB,GB etc.
      Parameters:
      locale - The locale to apply during formatting. If l is null then no localization is applied.
      bytes - number of bytes
      Returns:
      human readable output
      See Also:

    • humanReadableBytes

      public static String humanReadableBytes(long bytes)
      Outputs the bytes in human readable format in units of KB,MB,GB etc. The locale always used is the one returned by Locale.getDefault().
      Parameters:
      bytes - number of bytes
      Returns:
      human readable output
      See Also:

    • matches

      public static boolean matches(String pattern, String target)
      Check for string pattern matching with a number of strategies in the following order: - equals - null pattern always matches - * always matches - Ant style matching - Regexp
      Parameters:
      pattern - the pattern
      target - the string to test
      Returns:
      true if target matches the pattern

    • camelCaseToDash

      public static String camelCaseToDash(String text)
      Converts the string from camel case into dash format (helloGreatWorld -> hello-great-world)
      Parameters:
      text - the string
      Returns:
      the string camel cased

    • startsWithIgnoreCase

      public static boolean startsWithIgnoreCase(String text, String prefix)
      Does the string starts with the given prefix (ignore case).
      Parameters:
      text - the string
      prefix - the prefix

    • asEnumConstantValue

      public static String asEnumConstantValue(String value)
      Converts the value to an enum constant value that is in the form of upper cased with underscore.

    • splitWords

      public static String[] splitWords(String text)
      Split the text on words, eg hello/world => becomes array with hello in index 0, and world in index 1.

    • splitAsStream

      public static Stream<String> splitAsStream(CharSequence text, String regex)
      Creates a stream from the given input sequence around matches of the regex
      Parameters:
      text - the input
      regex - the expression used to split the input
      Returns:
      the stream of strings computed by splitting the input with the given regex

    • countOccurrence

      public static int countOccurrence(String text, String search)
      Returns the occurrence of a search string in to a string.
      Parameters:
      text - the text
      search - the string to search
      Returns:
      an integer reporting the number of occurrence of the searched string in to the text

    • replaceFromSecondOccurrence

      public static String replaceFromSecondOccurrence(String text, String search, String replacement)
      Replaces a string in to a text starting from his second occurrence.
      Parameters:
      text - the text
      search - the string to search
      replacement - the replacement for the string
      Returns:
      the string with the replacement

    • padString

      public static String padString(int level)
      Pad the string with leading spaces
      Parameters:
      level - level (2 blanks per level)

    • padString

      public static String padString(int level, int blanks)
      Pad the string with leading spaces
      Parameters:
      level - level
      blanks - number of blanks per level

    • fillChars

      public static String fillChars(char ch, int count)
      Fills the string with repeating chars
      Parameters:
      ch - the char
      count - number of chars

    • isDigit

      public static boolean isDigit(String s)