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Carrot2 search results clustering framework. Minimal functional subset
(core algorithms and infrastructure, no document sources).
/*
* Carrot2 project.
*
* Copyright (C) 2002-2019, Dawid Weiss, Stanisław Osiński.
* All rights reserved.
*
* Refer to the full license file "carrot2.LICENSE"
* in the root folder of the repository checkout or at:
* http://www.carrot2.org/carrot2.LICENSE
*/
package org.carrot2.util;
/**
* A number of useful methods for working with char [] arrays.
*/
public class CharArrayUtils
{
public final static char [] EMPTY_ARRAY = new char [0];
/**
* In place to lower case conversion. In input array is returned for convenience.
*/
public static char [] toLowerCaseInPlace(char [] array)
{
for (int i = array.length; --i >= 0;)
{
array[i] = Character.toLowerCase(array[i]);
}
return array;
}
/**
* To lower case conversion. A copy of the input array will be created.
*/
public static char [] toLowerCaseCopy(char [] array)
{
return toLowerCaseInPlace((char []) array.clone());
}
/**
* Computes and returns the ratio of capitalized
* letters in the string to the numbers of all letters.
*/
public static float getCapitalizedRatio(char [] string)
{
final int len = string.length;
if (len == 0) return 0;
int capitalized = 0;
for (int i = len; --i >= 0;)
{
if (Character.isUpperCase(string[i]))
capitalized++;
}
return capitalized / (float) len;
}
/**
* Returns true if the input array contains any capitalized
* characters.
*/
public static boolean hasCapitalizedLetters(char [] string)
{
for (int i = string.length; --i >= 0;)
{
if (Character.isUpperCase(string[i]))
return true;
}
return false;
}
/**
* Returns a capitalized copy of the input character array.
*/
public static char [] toCapitalizedCopy(char [] string)
{
final int len = string.length;
if (len == 0) return string;
final char [] lowerCase = toLowerCaseCopy(string);
lowerCase[0] = Character.toUpperCase(lowerCase[0]);
return lowerCase;
}
/**
* Convert to lower case (character-by-character) and save the result
* into buffer.
*
* @param word The word to be converted to lower case.
* @param buffer The buffer where the result should be saved.
* @return Returns true if at least one character was changed
* between word and buffer. false indicates
* an identical copy.
* @throws AssertionError If buffer is smaller than word.
*/
public static boolean toLowerCase(char [] word, char [] buffer)
{
return toLowerCase(word, buffer, 0, word.length);
}
/**
* Convert to lower case (character-by-character) and save the result
* into buffer. The buffer must have at least length
* characters.
*
* @param word The word to be converted to lower case.
* @param buffer The buffer where the result should be saved.
* @param start the index in the word at which to start
* @param length the number of characters from word to process
* @return Returns true if at least one character was changed
* between word and buffer. false indicates
* an identical copy.
* @throws AssertionError If buffer is smaller than length.
* @throws AssertionError If start + length is smaller than the length word.
*/
public static boolean toLowerCase(char [] word, char [] buffer, int start, int length)
{
assert buffer.length >= length: "Buffer too small.";
assert start + length <= word.length : "Word too short.";
assert start >= 0 : "Start must be >= 0";
boolean different = false;
char in, out;
for (int i = length; --i >= 0;)
{
buffer[i] = out = Character.toLowerCase(in = word[i + start]);
different |= (in != out);
}
return different;
}
}