org.jgrasstools.gears.io.grasslegacy.utils.JlsTokenizer Maven / Gradle / Ivy
/*
* JGrass - Free Open Source Java GIS http://www.jgrass.org
* (C) HydroloGIS - www.hydrologis.com
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 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 Lesser General Public License
* along with this program. If not, see
x,,y
yields a blank token between x
and y, whereas with StringTokenizer it is swallowed.
,a,
yields a blank token both before
and after a, whereas with StringTokenizer both are
swallowed.
Some pieces of StringTokenizer aren't supported, such
as returning delimiters and changing delimiters during
operation.
This class is deliberately not a subclass of
StringTokenizer as the behaviour is significantly
different. It can, however, be used in many places
where StringTokenizer is appropriate.
NOTES:
AUTHOR: JSkeet
EMAIL:
COMPANY:
COPYRIGHT:
VERSION:
CREATED:
REVISION: ---
******************************************************************************
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
******************************************************************************
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comments: changes
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*****************************************************************************/
package org.jgrasstools.gears.io.grasslegacy.utils;
//import java.util.NoSuchElementException;
public class JlsTokenizer
{
/* Data to parse */
private String data;
/* Length of data */
private int dataLength;
/* Delimiter string */
private String delimiters;
/* Current position. This is usually one place
* after the previously seen delimiter, so if the
* character at this position *is* a delimiter, the
* next token is empty. If the position is at the
* end of the string (after the last character), that
* shows that there is one final empty token to return.
* If the position is *past* the very end of the string
* (ie dataLength+1 or higher) then there are no more
* tokens. */
private int position=0;
/**
* Constructs a string tokenizer for the specified string. The
* tokenizer uses the default delimiter set, which is
* " \t\n\r\f": the space character,
* the tab character, the newline character, the carriage-return character,
* and the form-feed character. Delimiter characters themselves will
* not be treated as tokens.
*
* @param str a string to be parsed.
*/
public JlsTokenizer (String str)
{
this (str, "\t\n\r\f");
}
/**
* Constructs a string tokenizer for the specified string. The
* characters in the delim argument are the delimiters
* for separating tokens. Delimiter characters themselves will not
* be treated as tokens.
*
* @param str a string to be parsed.
* @param delim the delimiters.
*/
public JlsTokenizer (String str, String delim)
{
this.data = str;
this.delimiters=delim;
this.dataLength = data.length();
}
/**
* Tests if there are more tokens available from this tokenizer's string.
* If this method returns true, then a subsequent call to
* nextToken with no argument will successfully return a token.
*
* @return true if and only if there is at least one token
* in the string after the current position; false
* otherwise.
*/
public boolean hasMoreTokens()
{
return !(position > dataLength);
}
/**
* Returns the next token from this string tokenizer.
*
* @return the next token from this string tokenizer.
* @exception NoSuchElementException if there are no more tokens in this
* tokenizer's string.
*/
public String nextToken()
{
int delPos;
/* Scan for the next delimiter or end of data */
for (delPos = position; delPos < dataLength; delPos++)
{
char c = data.charAt (delPos);
if (delimiters.indexOf (c) != -1)
break;
}
/* Find out what the token should be */
String ret = data.substring (position, delPos);
/* Set the position to the next position */
position = delPos+1;
return ret;
}
/**
* Returns the rest of the string.
*
* @return the rest of the string.
* @exception NoSuchElementException if there are no more tokens in this
* tokenizer's string.
*/
public String remainingToken()
{
return data.substring(position);
// int delPos;
// /* Scan for the next delimiter or end of data */
// for (delPos = position; delPos < dataLength; delPos++)
// {
// char c = data.charAt (delPos);
// if (delimiters.indexOf (c) != -1)
// break;
// }
// /* Find out what the token should be */
// String ret = data.substring (position, delPos);
// /* Set the position to the next position */
// position = delPos+1;
// return ret;
}
/**
* Returns the same value as the hasMoreTokens
* method. It exists so that this class can implement the
* Enumeration interface.
*
* @return true if there are more tokens;
* false otherwise.
*/
public boolean hasMoreElements()
{
return hasMoreTokens();
}
/**
* Returns the same value as the nextToken method,
* except that its declared return value is Object rather than
* String. It exists so that this class can implement the
* Enumeration interface.
*
* @return the next token in the string.
* @exception NoSuchElementException if there are no more tokens in this
* tokenizer's string.
*/
public Object nextElement()
{
return nextToken();
}
/**
* Calculates the number of times that this tokenizer's
* nextToken method can be called before it generates an
* exception. The current position is not advanced.
*
* @return the number of tokens remaining in the string using the current
* delimiter set.
* @see uk.org.skeet.util.JlsTokenizer#nextToken()
*/
public int countTokens()
{
int savedPosition = position;
int count=0;
while (hasMoreTokens())
{
nextToken();
count++;
}
position = savedPosition;
return count;
}
}