org.mailster.util
Class StringUtilities

java.lang.Object
  org.mailster.util.StringUtilities

public class StringUtilities
extends java.lang.Object

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Mailster (C) 2007-2009 De Oliveira Edouard

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

See Mailster Web Site
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StringUtilities.java - Various methods to handle strings.

Version:

$Revision: 1.7 $, $Date: 2008/12/06 13:57:17 $

Author:

Edouard De Oliveira

Field Summary

static java.lang.String

EMPTY_STRING Constant for the empty String

Constructor Summary

StringUtilities()

Method Summary

private static void	extractDirective(java.util.HashMap<java.lang.String,java.lang.String> map, java.lang.String key, java.lang.String value) Processes directive/value pairs from the digest-challenge and fill out the provided map.
static java.lang.String	intToFixedLengthHex(int value, int length) Takes value and return its HEX value prefixed with zeros .
static boolean	isEmpty(java.lang.String str) Tests if the given String is empty.
static boolean	isLws(byte b) Is character a linear white space ?
static int	occ(java.lang.String s, char c, int start, int length) Returns the occurence count of char c in a substring of the String s starting at position start and containing length chars.
static java.util.HashMap<java.lang.String,java.lang.String>	parseDirectives(byte[] buf) Parses digest-challenge string, extracting each token and value(s)
static java.lang.String	replace(java.lang.String text, java.lang.String repl, java.lang.String with) Replaces all occurrences of a String within another String.
static java.lang.String	replace(java.lang.String text, java.lang.String repl, java.lang.String with, int max) Replaces a String with another String inside a larger String, for the first max values of the search String.
private static int	skipLws(byte[] buf, int start) Skip all linear white spaces
static java.lang.String[]	split(java.lang.String s) Split a String into an array of String[] using the space character as token.
static java.lang.String[]	split(java.lang.String s, java.lang.String token) Split a String into an array of String[].
static java.lang.String	stringTo_8859_1(java.lang.String str, boolean useUTF8) Used to convert username-value, passwd or realm to 8859_1 encoding if all chars in string are within the 8859_1 (Latin 1) encoding range.
static java.lang.String	strip(java.lang.String str) Strips whitespace from the start and end of a String.
static java.lang.String	strip(java.lang.String str, java.lang.String stripChars) Strips any of a set of characters from the start and end of a String.
static java.lang.String	stripEnd(java.lang.String str, java.lang.String stripChars) Strips any of a set of characters from the end of a String.
static java.lang.String	stripStart(java.lang.String str, java.lang.String stripChars) Strips any of a set of characters from the start of a String.

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 java.lang.String EMPTY_STRING

Constant for the empty String

See Also:

Constant Field Values

Constructor Detail

StringUtilities

public StringUtilities()

Method Detail

isEmpty

public static boolean isEmpty(java.lang.String str)

Tests if the given String is empty. A String object is considered empty if it is either null or its trimmed length is zero.

Parameters:

str - the String to test

Returns:

true if the given String is empty; false otherwise

split

public static java.lang.String[] split(java.lang.String s)

Split a String into an array of String[] using the space character as token.

Parameters:

s - the string to split

Returns:

the splitted string array

split

public static java.lang.String[] split(java.lang.String s,
                                       java.lang.String token)

Split a String into an array of String[].

Parameters:

s - the string to split

token - the character token

Returns:

the splitted string array

intToFixedLengthHex

public static java.lang.String intToFixedLengthHex(int value,
                                                   int length)

Takes value and return its HEX value prefixed with zeros .

Parameters:

value - the value to be converted

length - the length to pad to.

Returns:

a non-null String fixed width representing the HEX of value

stringTo_8859_1

public static java.lang.String stringTo_8859_1(java.lang.String str,
                                               boolean useUTF8)
                                        throws AuthException

Used to convert username-value, passwd or realm to 8859_1 encoding if all chars in string are within the 8859_1 (Latin 1) encoding range.

Parameters:

str - a non-null String

useUTF8 - a boolean value set to true if UT8 is in use.

Returns:

a non-null String containing the correct character encoding for username, paswd or realm.

Throws:

AuthException

occ

public static int occ(java.lang.String s,
                      char c,
                      int start,
                      int length)

Returns the occurence count of char c in a substring of the String s starting at position start and containing length chars.

Parameters:

s - the string to parse

c - the character to search for

Returns:

the occurence count

parseDirectives

public static java.util.HashMap<java.lang.String,java.lang.String> parseDirectives(byte[] buf)
                                                                            throws javax.security.sasl.SaslException

Parses digest-challenge string, extracting each token and value(s)

Parameters:

buf - A non-null digest-challenge string.

Throws:

java.io.UnsupportedEncodingException

javax.security.sasl.SaslException - if the String cannot be parsed according to RFC 2831

extractDirective

private static void extractDirective(java.util.HashMap<java.lang.String,java.lang.String> map,
                                     java.lang.String key,
                                     java.lang.String value)
                              throws javax.security.sasl.SaslException

Processes directive/value pairs from the digest-challenge and fill out the provided map.

Parameters:

key - A non-null String challenge token name.

value - A non-null String token value.

Throws:

javax.security.sasl.SaslException - if either the key or the value is null or if the key already has a value.

isLws

public static boolean isLws(byte b)

Is character a linear white space ? LWS = [CRLF] 1*( SP | HT ) Note that we're checking individual bytes instead of CRLF

Parameters:

b - the byte to check

Returns:

true if it's a linear white space

skipLws

private static int skipLws(byte[] buf,
                           int start)

Skip all linear white spaces

replace

public static java.lang.String replace(java.lang.String text,
                                       java.lang.String repl,
                                       java.lang.String with)

Replaces all occurrences of a String within another String.

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

 StringUtils.replace(null, *, *)        = null
 StringUtils.replace("", *, *)          = ""
 StringUtils.replace("any", null, *)    = "any"
 StringUtils.replace("any", *, null)    = "any"
 StringUtils.replace("any", "", *)      = "any"
 StringUtils.replace("aba", "a", null)  = "aba"
 StringUtils.replace("aba", "a", "")    = "b"
 StringUtils.replace("aba", "a", "z")   = "zbz"
 

Parameters:

text - text to search and replace in, may be null

repl - the String to search for, may be null

with - the String to replace with, may be null

Returns:

the text with any replacements processed, null if null String input

See Also:

replace(String text, String repl, String with, int max)

replace

public static java.lang.String replace(java.lang.String text,
                                       java.lang.String repl,
                                       java.lang.String with,
                                       int max)

Replaces a String with another String inside a larger String, for the first max values of the search String.

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

 StringUtils.replace(null, *, *, *)         = null
 StringUtils.replace("", *, *, *)           = ""
 StringUtils.replace("any", null, *, *)     = "any"
 StringUtils.replace("any", *, null, *)     = "any"
 StringUtils.replace("any", "", *, *)       = "any"
 StringUtils.replace("any", *, *, 0)        = "any"
 StringUtils.replace("abaa", "a", null, -1) = "abaa"
 StringUtils.replace("abaa", "a", "", -1)   = "b"
 StringUtils.replace("abaa", "a", "z", 0)   = "abaa"
 StringUtils.replace("abaa", "a", "z", 1)   = "zbaa"
 StringUtils.replace("abaa", "a", "z", 2)   = "zbza"
 StringUtils.replace("abaa", "a", "z", -1)  = "zbzz"
 

Parameters:

text - text to search and replace in, may be null

repl - the String to search for, may be null

with - the String to replace with, may be null

max - maximum number of values to replace, or -1 if no maximum

Returns:

the text with any replacements processed, null if null String input

strip

public static java.lang.String strip(java.lang.String str)

Strips whitespace from the start and end of a String.

This is similar to String.trim() but removes whitespace. Whitespace is defined by Character.isWhitespace(char).

A null input String returns null.

 StringUtils.strip(null)     = null
 StringUtils.strip("")       = ""
 StringUtils.strip("   ")    = ""
 StringUtils.strip("abc")    = "abc"
 StringUtils.strip("  abc")  = "abc"
 StringUtils.strip("abc  ")  = "abc"
 StringUtils.strip(" abc ")  = "abc"
 StringUtils.strip(" ab c ") = "ab c"
 

Parameters:

str - the String to remove whitespace from, may be null

Returns:

the stripped String, null if null String input

strip

public static java.lang.String strip(java.lang.String str,
                                     java.lang.String stripChars)

Strips any of a set of characters from the start and end of a String. This is similar to String.trim() but allows the characters to be stripped to be controlled.

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

If the stripChars String is null, whitespace is stripped as defined by Character.isWhitespace(char). Alternatively use strip(String).

 StringUtils.strip(null, *)          = null
 StringUtils.strip("", *)            = ""
 StringUtils.strip("abc", null)      = "abc"
 StringUtils.strip("  abc", null)    = "abc"
 StringUtils.strip("abc  ", null)    = "abc"
 StringUtils.strip(" abc ", null)    = "abc"
 StringUtils.strip("  abcyx", "xyz") = "  abc"
 

Parameters:

str - the String to remove characters from, may be null

stripChars - the characters to remove, null treated as whitespace

Returns:

the stripped String, null if null String input

stripStart

public static java.lang.String stripStart(java.lang.String str,
                                          java.lang.String stripChars)

Strips any of a set of characters from the start of a String.

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

If the stripChars String is null, whitespace is stripped as defined by Character.isWhitespace(char).

 StringUtils.stripStart(null, *)          = null
 StringUtils.stripStart("", *)            = ""
 StringUtils.stripStart("abc", "")        = "abc"
 StringUtils.stripStart("abc", null)      = "abc"
 StringUtils.stripStart("  abc", null)    = "abc"
 StringUtils.stripStart("abc  ", null)    = "abc  "
 StringUtils.stripStart(" abc ", null)    = "abc "
 StringUtils.stripStart("yxabc  ", "xyz") = "abc  "
 

Parameters:

str - the String to remove characters from, may be null

stripChars - the characters to remove, null treated as whitespace

Returns:

the stripped String, null if null String input

stripEnd

public static java.lang.String stripEnd(java.lang.String str,
                                        java.lang.String stripChars)

Strips any of a set of characters from the end of a String.

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

If the stripChars String is null, whitespace is stripped as defined by Character.isWhitespace(char).

 StringUtils.stripEnd(null, *)          = null
 StringUtils.stripEnd("", *)            = ""
 StringUtils.stripEnd("abc", "")        = "abc"
 StringUtils.stripEnd("abc", null)      = "abc"
 StringUtils.stripEnd("  abc", null)    = "  abc"
 StringUtils.stripEnd("abc  ", null)    = "abc"
 StringUtils.stripEnd(" abc ", null)    = " abc"
 StringUtils.stripEnd("  abcyx", "xyz") = "  abc"
 

Parameters:

str - the String to remove characters from, may be null

stripChars - the characters to remove, null treated as whitespace

Returns:

the stripped String, null if null String input