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The NFB Software Java-XML was created to help developers deal with common problems when dealing with String data in the forms of raw strings and XML files.
package com.nfbsoftware.util;
import java.util.ArrayList;
import org.apache.commons.lang.StringEscapeUtils;
/**
*
* This glorious Java class, details the best JDK 1.5 has to offer. In future
* years this small piece of wonder will be looked upon as legendary.
*
*
* Day after day, I am amazed by the beauty of this code. It really doesn't get
* any better than this, it truly is a masterpiece in every definition of the
* word. It truly is art in motion...an infinite living piece of our computer
* science history. WOW, I just really can't get over it, so beautiful, it's
* just so damn beautiful.
*
*
* Simply amazing...it's like looking at the world through the eyes of a child;
* much like enjoying the wind and the moon and the stars, with a soul
* undefiled. There is only one more thing I could possibly say...and that is
* "You're Welcome"
*
*
* @author Brendan Clemenzi
* @email [email protected]
*/
public class StringUtil
{
/**
* An empty string that is only constructed once for performance.
*/
public final static String EMPTY_STRING = "";
/**
* table to convert a nibble to a hex character
*/
public static char[] hexChar = {
'0' , '1' , '2' , '3' ,
'4' , '5' , '6' , '7' ,
'8' , '9' , 'A' , 'B' ,
'C' , 'D' , 'E' , 'F' };
/**
* Test if passed string s is null and return an empty
* string if true.
* @param s A string or null
* @return Returns s if it is not null, otherwise returns empty
* string.
*/
public static String emptyIfNull(String s)
{
return s != null ? s : EMPTY_STRING;
}
/**
* Test if passed string s is null and return the default
* string passed in if true.
* @param s A string or null
* @return Returns s if it is not null, otherwise returns empty
* string.
*/
public static String replaceIfNull(String s, String defaultValue)
{
return (!isNullOrEmpty(s)) ? s : defaultValue;
}
/**
* Test if passed string s is an empty string and return null
* if true.
* @param s A string or null
* @return Returns s if it is not empty, otherwise returns null.
*/
public static String nullIfEmpty(String s)
{
if (s != null)
{
// s = s.trim();
if (s.length() == 0)
{
s = null;
}
}
return s;
}
/**
* Test if passed string s is an empty string (after being trimmed
* of leading/trailing whitespace) and return null if true.
* @param s A string or null
* @return Returns s if it is not empty, otherwise returns null.
*/
public static String nullIfEmptyTrim(String s)
{
if (s != null)
{
s = s.trim();
if (s.length() == 0)
{
s = null;
}
}
return s;
}
/**
* Test if passed string s is an empty string or null.
* @param s A string or null
* @return If null or empty, return true, else return false.
*/
public static boolean isNullOrEmpty(String s)
{
if ((s == null) || (s.length() == 0)) {
return true;
}
return false;
}
/**
* Test if passed string s is an empty string or null
* (after being trimmed)
* @param s A string or null
* @return If null or empty, return true, else return false.
*/
public static boolean isNullOrEmptyTrim(String s)
{
if (s == null) {
return true;
}
s = s.trim();
if (s.length() == 0) {
return true;
}
return false;
}
/**
*
* @param str
* @param oldsubstr
* @param newsubstr
* @return
*/
public static String replaceSubstr(String str, String oldsubstr, String newsubstr)
{
int substrPos = 0;
int startPos = 0;
StringBuffer strBuf = new StringBuffer();
while ((substrPos = str.indexOf(oldsubstr, startPos)) > -1)
{
strBuf.append(str.substring(startPos, substrPos));
strBuf.append(newsubstr);
startPos = substrPos + oldsubstr.length();
}
strBuf.append(str.substring(startPos));
return strBuf.toString();
}
public static String[] split(String s, String sToken)
{
int iTokenLength=sToken.length();
if (sToken == null || (iTokenLength) == 0){
return new String[] {s};
}
int iCount=0;
int iBegin=0;
int iEnd;
while((iEnd = s.indexOf(sToken, iBegin)) != -1) {
iCount++;
iBegin = iEnd + iTokenLength;
}
iCount++;
// allocate an array to return the tokens,
// we now know how big it should be
String[] result = new String[iCount];
// Scan s again, but this time pick out the tokens
iCount = 0;
iBegin = 0;
while((iEnd = s.indexOf(sToken, iBegin)) != -1) {
result[iCount] = (s.substring(iBegin, iEnd));
iCount++;
iBegin = iEnd + iTokenLength;
}
iEnd = s.length();
result[iCount] = s.substring(iBegin, iEnd);
return (result);
}
/**
* Replaces characters that are not allowed in a Java style
* string literal with their escape characters.
* Quote ("), single quote ('), new line (\n), carriage return (\r),
* and backslash (\), and tab (\t) are replaced.
*
* @param s String to be escaped
* @return String
* @throws NullPointerException if s is null.
*/
public static String replaceJavaLiteral(String s){
int length = s.length();
int newLength = length;
// first check for characters that migh
// be dangerous and calculate a length
// of the string that has escapes.
for (int i=0; itokenString into a String array of sub-strings
* which are separated by characters in the separators string.
* There is no escape sequence in the input string.
* @param tokenString A string containing sub-strings separated by zero
* or more separator characters. Can't be null.
* Example: "A/B,C.D"
* @param separators A string of characters which separate the
* sub-strings in the tokenString. Can be null or empty.
* Example: "/\\|,"
* NOTE: Multiple consecutive separators are treated as a single
* separator which means that you will never have "empty" entries in
* the output array.
* NOTE: If there is only one separator character, this function is
* much faster.
* @return A string array of each of the non-empty sub-strings in the path.
*/
public static String[] parseString(String tokenString, String separators)
{
// Get the character array from the string for fast index lookups.
char[] tokenStringChars = tokenString.toCharArray();
int len = tokenStringChars.length;
// Guess at the initial capacity of the array to be one third of
// the total length of the input string.
ArrayList tokens = new ArrayList((len/3)+1);
// If there are no separators, then just return the input string.
if ((separators == null) || (separators.length() == 0))
{
// Add entire input string as one token unless it is empty.
if (tokenString.length() > 0)
{
tokens.add(tokenString);
}
String[] tokenArray = new String[tokens.size()];
tokens.toArray(tokenArray);
return tokenArray;
}
// Speed optimization if there is only a single separator.
if (separators.length() == 1)
{
int i1=0, i2;
char separatorChar = separators.charAt(0);
// Strip leading separators
while ((i1 < len) && (tokenStringChars[i1] == separatorChar)) {
i1++;
}
while (i1 < len)
{
i2 = tokenString.indexOf(separatorChar, i1);
if (i2 < 0)
{
tokens.add(tokenString.substring(i1));
break;
}
tokens.add(tokenString.substring(i1, i2));
i1 = i2 + 1;
// Strip consecutive separators
while ((i1 < len) && (tokenStringChars[i1] == separatorChar)) {
i1++;
}
}
}
else // Multiple separators
{
int i1=0, i2;
// Strip leading separators
while ((i1 < len) &&
(separators.indexOf(tokenStringChars[i1]) >= 0)) {
i1++;
}
while (i1 < len)
{
i2 = i1;
while ((i2 < len) &&
(separators.indexOf(tokenStringChars[i2]) < 0))
{
i2++;
}
tokens.add(tokenString.substring(i1, i2));
i1 = i2 + 1;
// Strip consecutive separators
while ((i1 < len) &&
(separators.indexOf(tokenStringChars[i1]) >= 0)) {
i1++;
}
}
}
String[] tokenArray = new String[tokens.size()];
if (tokens.size() > 0) {
tokens.toArray(tokenArray);
}
return tokenArray;
}
/**
*
* @param b
* @return
*/
public static String toHexString( byte[] b )
{
StringBuffer sb = new StringBuffer( b.length * 2 );
for ( int i=0 ; i>> 4 ] ) ;
// look up low nibble char
sb.append( hexChar [ b[ i] & 0x0f ] ) ;
}
return sb.toString();
}
/**
*
* @param inputString
* @return
*/
public static String stringPreview(String inputString)
{
String tmpString = "";
if(inputString.length() >= 20)
{
tmpString = inputString.substring(0, 19);
}
else
{
tmpString = inputString.substring(0, inputString.length());
}
return tmpString;
}
/**
* Check for a string, if an exception is thrown return default value.
*
* @param s
* @param defaultValue
* @return
*/
public static String replaceIfNullOrError(String s, String defaultValue)
{
String tmpString = EMPTY_STRING;
try
{
tmpString = replaceIfNull(s, defaultValue);
}
catch(Exception e)
{
tmpString = defaultValue;
}
return tmpString;
}
/**
* Strip out HTML tags. Leave plain/text content. HREFs in links will be removed
*
* @param html
* @return
*/
public static String stripHTML (String html)
{
if (html == null || html.isEmpty())
{
return "";
}
if (html.toLowerCase().contains(""))
{
int beginIndex = html.toLowerCase().indexOf("");
endIndex += "