StringUtil (Netty API Reference (4.1.115.Final))

java.lang.Object
- io.netty.util.internal.StringUtil

public final class StringUtil
extends Object

String utility class.

Field Summary

Fields
Modifier and Type	Field and Description
`static char`	`CARRIAGE_RETURN`
`static char`	`COMMA`
`static char`	`DOUBLE_QUOTE`
`static String`	`EMPTY_STRING`
`static char`	`LINE_FEED`
`static String`	`NEWLINE`
`static char`	`SPACE`
`static char`	`TAB`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static String`	`byteToHexString(int value)` Converts the specified byte value into a hexadecimal integer.
`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.
`static String`	`byteToHexStringPadded(int value)` Converts the specified byte value into a 2-digit hexadecimal integer.
`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.
`static boolean`	`commonSuffixOfLength(String s, String p, int len)` Checks if two strings have the same suffix of specified length
`static byte`	`decodeHexByte(CharSequence s, int pos)` Decode a 2-digit hex byte from within a string.
`static byte[]`	`decodeHexDump(CharSequence hexDump)` Decodes a hex dump
`static byte[]`	`decodeHexDump(CharSequence hexDump, int fromIndex, int length)` Decodes part of a string with hex dump
`static int`	`decodeHexNibble(byte b)` Helper to decode half of a hexadecimal number from a string.
`static int`	`decodeHexNibble(char c)` Helper to decode half of a hexadecimal number from a string.
`static boolean`	`endsWith(CharSequence s, char c)` Determine if the string `s` ends with the char `c`.
`static CharSequence`	`escapeCsv(CharSequence value)` Escapes the specified value, if necessary according to RFC-4180.
`static CharSequence`	`escapeCsv(CharSequence value, boolean trimWhiteSpace)` Escapes the specified value, if necessary according to RFC-4180.
`static int`	`indexOfNonWhiteSpace(CharSequence seq, int offset)` Find the index of the first non-white space character in `s` starting at `offset`.
`static int`	`indexOfWhiteSpace(CharSequence seq, int offset)` Find the index of the first white space character in `s` starting at `offset`.
`static boolean`	`isNullOrEmpty(String s)` Determine if a string is `null` or `String.isEmpty()` returns `true`.
`static boolean`	`isSurrogate(char c)` Determine if `c` lies within the range of values defined for Surrogate Code Point.
`static CharSequence`	`join(CharSequence separator, Iterable<? extends CharSequence> elements)` Returns a char sequence that contains all `elements` joined by a given separator.
`static int`	`length(String s)` Get the length of a string, `null` input is considered `0` length.
`static String`	`simpleClassName(Class<?> clazz)` Generates a simplified name from a `Class`.
`static String`	`simpleClassName(Object o)` The shortcut to `simpleClassName(o.getClass())`.
`static String`	`substringAfter(String value, char delim)` Get the item after one char delim if the delim is found (else null).
`static String`	`substringBefore(String value, char delim)` Get the item before one char delim if the delim is found (else null).
`static String`	`toHexString(byte[] src)` Converts the specified byte array into a hexadecimal value.
`static String`	`toHexString(byte[] src, int offset, int length)` Converts the specified byte array into a hexadecimal value.
`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.
`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.
`static String`	`toHexStringPadded(byte[] src)` Converts the specified byte array into a hexadecimal value.
`static String`	`toHexStringPadded(byte[] src, int offset, int length)` Converts the specified byte array into a hexadecimal value.
`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.
`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.
`static CharSequence`	`trimOws(CharSequence value)` Trim optional white-space characters from the specified value, according to RFC-7230.
`static CharSequence`	`unescapeCsv(CharSequence value)` Unescapes the specified escaped CSV field, if necessary according to RFC-4180.
`static List<CharSequence>`	`unescapeCsvFields(CharSequence value)` Unescapes the specified escaped CSV fields according to RFC-4180.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - EMPTY_STRING
```
public static final String EMPTY_STRING
```
    See Also:
    
    Constant Field Values
  - NEWLINE
```
public static final String NEWLINE
```
  - DOUBLE_QUOTE
```
public static final char DOUBLE_QUOTE
```
    See Also:
    
    Constant Field Values
  - COMMA
```
public static final char COMMA
```
    See Also:
    
    Constant Field Values
  - LINE_FEED
```
public static final char LINE_FEED
```
    See Also:
    
    Constant Field Values
  - CARRIAGE_RETURN
```
public static final char CARRIAGE_RETURN
```
    See Also:
    
    Constant Field Values
  - TAB
```
public static final char TAB
```
    See Also:
    
    Constant Field Values
  - SPACE
```
public static final char SPACE
```
    See Also:
    
    Constant Field Values
- Method Detail
  - 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
  - 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.

Class StringUtil

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

EMPTY_STRING

NEWLINE

DOUBLE_QUOTE

COMMA

LINE_FEED

CARRIAGE_RETURN

TAB

SPACE

Method Detail

substringAfter

substringBefore

commonSuffixOfLength

byteToHexStringPadded

byteToHexStringPadded

toHexStringPadded

toHexStringPadded

toHexStringPadded

toHexStringPadded

byteToHexString

byteToHexString

toHexString

toHexString

toHexString

toHexString

decodeHexNibble

decodeHexNibble

decodeHexByte

decodeHexDump

decodeHexDump

simpleClassName

simpleClassName

escapeCsv

escapeCsv

unescapeCsv

unescapeCsvFields

length

isNullOrEmpty

indexOfNonWhiteSpace

indexOfWhiteSpace

isSurrogate

endsWith

trimOws

join