Module org.htmlunit
Package org.htmlunit.util

Class StringUtils

java.lang.Object
org.htmlunit.util.StringUtils
public final class StringUtils extends Object
String utilities class for utility functions not covered by third party libraries.
Author:
Daniel Gredler, Ahmed Ashour, Martin Tamme, Ronald Brill

  • Field Details

  • Method Details

    • isEmptyString

      public static boolean isEmptyString(CharSequence s)
      Returns true if the param is not null and empty. This is different from StringUtils.isEmpty(CharSequence) because this returns false if the provided string is null.
      Parameters:
      s - the string to check
      Returns:
      true if the param is not null and empty

    • isEmptyOrNull

      public static boolean isEmptyOrNull(CharSequence s)
      Returns true if the param is null or empty.
      Parameters:
      s - the string to check
      Returns:
      true if the param is null or empty

    • defaultIfEmptyOrNull

      public static <T extends CharSequence> T defaultIfEmptyOrNull(T s, T defaultString)
      Returns either the passed in CharSequence, or if the CharSequence is empty or null, the default value.
      Type Parameters:
      T - the kind of CharSequence
      Parameters:
      s - the CharSequence to check
      defaultString - the default to return if the input is empty or null
      Returns:
      the passed in CharSequence, or the defaultString

    • isBlank

      public static boolean isBlank(CharSequence s)
      Tests if a CharSequence is null, empty, or contains only whitespace.
      Parameters:
      s - the CharSequence to check
      Returns:
      true if a CharSequence is null, empty, or contains only whitespace

    • isNotBlank

      public static boolean isNotBlank(CharSequence s)
      Tests if a CharSequence is NOT null, empty, or contains only whitespace.
      Parameters:
      s - the CharSequence to check
      Returns:
      false if a CharSequence is null, empty, or contains only whitespace

    • equalsChar

      public static boolean equalsChar(char expected, CharSequence s)
      Parameters:
      expected - the char that we expect
      s - the string to check
      Returns:
      true if the provided string has only one char and this matches the expectation

    • startsWithIgnoreCase

      public static boolean startsWithIgnoreCase(String s, String expectedStart)
      Tests if a CharSequence starts with a specified prefix.
      Parameters:
      s - the string to check
      expectedStart - the string that we expect at the beginning (has to be not null and not empty)
      Returns:
      true if the provided string has only one char and this matches the expectation

    • endsWithIgnoreCase

      public static boolean endsWithIgnoreCase(String s, String expectedEnd)
      Tests if a CharSequence ends with a specified prefix.
      Parameters:
      s - the string to check
      expectedEnd - the string that we expect at the end (has to be not null and not empty)
      Returns:
      true if the provided string has only one char and this matches the expectation

    • containsIgnoreCase

      public static boolean containsIgnoreCase(String s, String expected)
      Tests if a CharSequence ends with a specified prefix.
      Parameters:
      s - the string to check
      expected - the string that we expect to be a substring (has to be not null and not empty)
      Returns:
      true if the provided string has only one char and this matches the expectation

    • replaceChars

      public static String replaceChars(String str, String searchChars, String replaceChars)
      Replaces multiple characters in a String in one go. This method can also be used to delete characters.
      Parameters:
      str - String to replace characters in, may be null.
      searchChars - a set of characters to search for, may be null.
      replaceChars - a set of characters to replace, may be null.
      Returns:
      modified String, or the input string if no replace was done.

    • substringAfter

      public static String substringAfter(String str, String find)
      Gets the substring after the first occurrence of a separator. The separator is not returned.

      A null string input will return null. An empty ("") string input will return the empty string. A null separator will return the empty string if the input string is not null.

      If nothing is found, the empty string is returned.

      Parameters:
      str - the String to get a substring from, may be null.
      find - the String to find, may be null.
      Returns:
      the substring after the first occurrence of the specified string, null if null String input.

    • escapeXmlChars

      public static String escapeXmlChars(String s)
      Escapes the characters '<', '>' and '&' into their XML entity equivalents.
      Parameters:
      s - the string to escape
      Returns:
      the escaped form of the specified string

    • escapeXml

      public static String escapeXml(String text)
      Escape the string to be used as xml 1.0 content be replacing the characters '"', '&', ''', '<', and '>' into their XML entity equivalents.
      Parameters:
      text - the attribute value
      Returns:
      the escaped value

    • escapeXmlAttributeValue

      public static String escapeXmlAttributeValue(String attValue)
      Escape the string to be used as attribute value. Only <, & and " have to be escaped (see http://www.w3.org/TR/REC-xml/#d0e888).
      Parameters:
      attValue - the attribute value
      Returns:
      the escaped value

    • indexOf

      public static int indexOf(String s, char searchChar, int beginIndex, int endIndex)
      Returns the index within the specified string of the first occurrence of the specified search character.
      Parameters:
      s - the string to search
      searchChar - the character to search for
      beginIndex - the index at which to start the search
      endIndex - the index at which to stop the search
      Returns:
      the index of the first occurrence of the character in the string or -1

    • asColorHexadecimal

      public static Color asColorHexadecimal(String token)
      Returns a Color parsed from the given RGB in hexadecimal notation.
      Parameters:
      token - the token to parse
      Returns:
      a Color whether the token is a color RGB in hexadecimal notation; otherwise null

    • findColorRGB

      public static Color findColorRGB(String token)
      Returns a Color parsed from the given rgb notation if found inside the given string.
      Parameters:
      token - the token to parse
      Returns:
      a Color whether the token contains a color in RGB notation; otherwise null

    • findColorRGBA

      public static Color findColorRGBA(String token)
      Returns a Color parsed from the given rgb notation.
      Parameters:
      token - the token to parse
      Returns:
      a Color whether the token is a color in RGB notation; otherwise null

    • findColorHSL

      public static Color findColorHSL(String token)
      Returns a Color parsed from the given hsl notation if found inside the given string.
      Parameters:
      token - the token to parse
      Returns:
      a Color whether the token contains a color in RGB notation; otherwise null

    • formatColor

      public static String formatColor(Color color)
      Formats the specified color.
      Parameters:
      color - the color to format
      Returns:
      the specified color, formatted

    • sanitizeForAppendReplacement

      public static String sanitizeForAppendReplacement(String toSanitize)
      Sanitize a string for use in Matcher.appendReplacement. Replaces all \ with \\ and $ as \$ because they are used as control characters in appendReplacement.
      Parameters:
      toSanitize - the string to sanitize
      Returns:
      sanitized version of the given string

    • sanitizeForFileName

      public static String sanitizeForFileName(String toSanitize)
      Sanitizes a string for use as filename. Replaces \, /, |, :, ?, *, ", <, >, control chars by _ (underscore).
      Parameters:
      toSanitize - the string to sanitize
      Returns:
      sanitized version of the given string

    • cssCamelize

      public static String cssCamelize(String string)
      Transforms the specified string from delimiter-separated (e.g. font-size) to camel-cased (e.g. fontSize).
      Parameters:
      string - the string to camelize
      Returns:
      the transformed string

    • toRootLowerCase

      public static String toRootLowerCase(String s)
      Lowercases a string by checking and check for null first. There is no cache involved and the ROOT locale is used to convert it.
      Parameters:
      s - the string to lowercase
      Returns:
      the lowercased string

    • toByteArray

      public static byte[] toByteArray(String content, Charset charset)
      Converts a string into a byte array using the specified encoding.
      Parameters:
      charset - the charset
      content - the string to convert
      Returns:
      the String as a byte[]; if the specified encoding is not supported an empty byte[] will be returned

    • splitAtJavaWhitespace

      public static String[] splitAtJavaWhitespace(String str)
      Splits the provided text into an array, using whitespace as the separator. Whitespace is defined by Character.isWhitespace(char).
      Parameters:
      str - the String to parse, may be null
      Returns:
      an array of parsed Strings, an empty array if null String input

    • splitAtBlank

      public static String[] splitAtBlank(String str)
      Splits the provided text into an array, using blank as the separator.
      Parameters:
      str - the String to parse, may be null
      Returns:
      an array of parsed Strings, an empty array if null String input

    • splitAtComma

      public static String[] splitAtComma(String str)
      Splits the provided text into an array, using blank as the separator.
      Parameters:
      str - the String to parse, may be null
      Returns:
      an array of parsed Strings, an empty array if null String input

    • splitAtCommaOrBlank

      public static String[] splitAtCommaOrBlank(String str)
      Splits the provided text into an array, using comma or blank as the separator.
      Parameters:
      str - the String to parse, may be null
      Returns:
      an array of parsed Strings, an empty array if null String input

    • substringBefore

      public static String substringBefore(String str, String find)
      Gets the substring before the first occurrence of a separator. The separator is not returned. A null string input will return null. An empty ("") string input will return the empty string. A null or empty separator is not allowed (will throw).
      Parameters:
      str - the String to get a substring from, may be null.
      find - the String to find, not null and not empty
      Returns:
      the substring before the first occurrence of the specified string, null if null String input.

    • toInt

      public static int toInt(String str, int defaultValue)
      Tries to converts a String into an int, returning a default value if the conversion fails. If the string is null, the default value is returned.
      Parameters:
      str - the string to convert, may be null.
      defaultValue - the default value.
      Returns:
      the int represented by the string, or the default if conversion fails or the provides str is null

    • toFloat

      public static float toFloat(String str, float defaultValue)
      Tries to converts a String into an float, returning a default value if the conversion fails. If the string is null, the default value is returned.
      Parameters:
      str - the string to convert, may be null.
      defaultValue - the default value.
      Returns:
      the float represented by the string, or the default if conversion fails or the provides str is null

    • trimRight

      public static String trimRight(String str)
      Strips any whitespace from the end of a String.

      A null input String returns null. An empty string ("") input returns the empty string.

      Parameters:
      str - the String to remove characters from, may be null.
      Returns:
      the stripped String, null if null String input.

    • containsOnly

      public static boolean containsOnly(CharSequence cs, char... valid)
      Parameters:
      cs - the String to check, may be null.
      valid - an array of valid chars, may be null.
      Returns:
      true if it only contains valid chars and is non-null.