Class StringUtil

java.lang.Object
io.netty.util.internal.StringUtil
public final class StringUtil extends Object
String utility class.

  • Field Details

  • Method Details

    • substringAfter

      public static String substringAfter(String value, char delim)
      Get the item after one char delim if the delim is found (else null). This operation is a simplified and optimized version of String.split(String, int).

    • substringBefore

      public static String substringBefore(String value, char delim)
      Get the item before one char delim if the delim is found (else null). This operation is a simplified and optimized version of String.split(String, int).

    • commonSuffixOfLength

      public static boolean commonSuffixOfLength(String s, String p, int len)
      Checks if two strings have the same suffix of specified length
      Parameters:
      s - string
      p - string
      len - length of the common suffix
      Returns:
      true if both s and p are not null and both have the same suffix. Otherwise - false

    • byteToHexStringPadded

      public static String byteToHexStringPadded(int value)
      Converts the specified byte value into a 2-digit hexadecimal integer.

    • byteToHexStringPadded

      public static <T extends Appendable> T byteToHexStringPadded(T buf, int value)
      Converts the specified byte value into a 2-digit hexadecimal integer and appends it to the specified buffer.

    • toHexStringPadded

      public static String toHexStringPadded(byte[] src)
      Converts the specified byte array into a hexadecimal value.

    • toHexStringPadded

      public static String toHexStringPadded(byte[] src, int offset, int length)
      Converts the specified byte array into a hexadecimal value.

    • toHexStringPadded

      public static <T extends Appendable> T toHexStringPadded(T dst, byte[] src)
      Converts the specified byte array into a hexadecimal value and appends it to the specified buffer.

    • toHexStringPadded

      public static <T extends Appendable> T toHexStringPadded(T dst, byte[] src, int offset, int length)
      Converts the specified byte array into a hexadecimal value and appends it to the specified buffer.

    • byteToHexString

      public static String byteToHexString(int value)
      Converts the specified byte value into a hexadecimal integer.

    • byteToHexString

      public static <T extends Appendable> T byteToHexString(T buf, int value)
      Converts the specified byte value into a hexadecimal integer and appends it to the specified buffer.

    • toHexString

      public static String toHexString(byte[] src)
      Converts the specified byte array into a hexadecimal value.

    • toHexString

      public static String toHexString(byte[] src, int offset, int length)
      Converts the specified byte array into a hexadecimal value.

    • toHexString

      public static <T extends Appendable> T toHexString(T dst, byte[] src)
      Converts the specified byte array into a hexadecimal value and appends it to the specified buffer.

    • toHexString

      public static <T extends Appendable> T toHexString(T dst, byte[] src, int offset, int length)
      Converts the specified byte array into a hexadecimal value and appends it to the specified buffer.

    • decodeHexNibble

      public static int decodeHexNibble(char c)
      Helper to decode half of a hexadecimal number from a string.
      Parameters:
      c - The ASCII character of the hexadecimal number to decode. Must be in the range [0-9a-fA-F].
      Returns:
      The hexadecimal value represented in the ASCII character given, or -1 if the character is invalid.

    • decodeHexNibble

      public static int decodeHexNibble(byte b)
      Helper to decode half of a hexadecimal number from a string.
      Parameters:
      b - The ASCII character of the hexadecimal number to decode. Must be in the range [0-9a-fA-F].
      Returns:
      The hexadecimal value represented in the ASCII character given, or -1 if the character is invalid.

    • decodeHexByte

      public static byte decodeHexByte(CharSequence s, int pos)
      Decode a 2-digit hex byte from within a string.

    • decodeHexDump

      public static byte[] decodeHexDump(CharSequence hexDump, int fromIndex, int length)
      Decodes part of a string with hex dump
      Parameters:
      hexDump - a CharSequence which contains the hex dump
      fromIndex - start of hex dump in hexDump
      length - hex string length

    • decodeHexDump

      public static byte[] decodeHexDump(CharSequence hexDump)
      Decodes a hex dump

    • className

      public static String className(Object o)
      Generates a class name from a Class. Similar to Class.getName(), but null-safe.

    • simpleClassName

      public static String simpleClassName(Object o)
      The shortcut to simpleClassName(o.getClass()).

    • simpleClassName

      public static String simpleClassName(Class<?> clazz)
      Generates a simplified name from a Class. Similar to Class.getSimpleName(), but it works fine with anonymous classes.

    • escapeCsv

      public static CharSequence escapeCsv(CharSequence value)
      Escapes the specified value, if necessary according to RFC-4180.
      Parameters:
      value - The value which will be escaped according to RFC-4180
      Returns:
      CharSequence the escaped value if necessary, or the value unchanged

    • escapeCsv

      public static CharSequence escapeCsv(CharSequence value, boolean trimWhiteSpace)
      Escapes the specified value, if necessary according to RFC-4180.
      Parameters:
      value - The value which will be escaped according to RFC-4180
      trimWhiteSpace - The value will first be trimmed of its optional white-space characters, according to RFC-7230
      Returns:
      CharSequence the escaped value if necessary, or the value unchanged

    • unescapeCsv

      public static CharSequence unescapeCsv(CharSequence value)
      Unescapes the specified escaped CSV field, if necessary according to RFC-4180.
      Parameters:
      value - The escaped CSV field which will be unescaped according to RFC-4180
      Returns:
      CharSequence the unescaped value if necessary, or the value unchanged

    • unescapeCsvFields

      public static List<CharSequence> unescapeCsvFields(CharSequence value)
      Unescapes the specified escaped CSV fields according to RFC-4180.
      Parameters:
      value - A string with multiple CSV escaped fields which will be unescaped according to RFC-4180
      Returns:
      List the list of unescaped fields

    • length

      public static int length(String s)
      Get the length of a string, null input is considered 0 length.

    • isNullOrEmpty

      public static boolean isNullOrEmpty(String s)
      Determine if a string is null or String.isEmpty() returns true.

    • indexOfNonWhiteSpace

      public static int indexOfNonWhiteSpace(CharSequence seq, int offset)
      Find the index of the first non-white space character in s starting at offset.
      Parameters:
      seq - The string to search.
      offset - The offset to start searching at.
      Returns:
      the index of the first non-white space character or <-1 if none was found.

    • indexOfWhiteSpace

      public static int indexOfWhiteSpace(CharSequence seq, int offset)
      Find the index of the first white space character in s starting at offset.
      Parameters:
      seq - The string to search.
      offset - The offset to start searching at.
      Returns:
      the index of the first white space character or <-1 if none was found.

    • isSurrogate

      public static boolean isSurrogate(char c)
      Determine if c lies within the range of values defined for Surrogate Code Point.
      Parameters:
      c - the character to check.
      Returns:
      true if c lies within the range of values defined for Surrogate Code Point. false otherwise.

    • endsWith

      public static boolean endsWith(CharSequence s, char c)
      Determine if the string s ends with the char c.
      Parameters:
      s - the string to test
      c - the tested char
      Returns:
      true if s ends with the char c

    • trimOws

      public static CharSequence trimOws(CharSequence value)
      Trim optional white-space characters from the specified value, according to RFC-7230.
      Parameters:
      value - the value to trim
      Returns:
      CharSequence the trimmed value if necessary, or the value unchanged

    • join

      public static CharSequence join(CharSequence separator, Iterable<? extends CharSequence> elements)
      Returns a char sequence that contains all elements joined by a given separator.
      Parameters:
      separator - for each element
      elements - to join together
      Returns:
      a char sequence joined by a given separator.