Java String Occurence Count countOccurences(String str, int ch)

Description

Return the number of occurences of a character in a string.

License

Open Source License

Parameter

Parameter	Description
str	The string to check.
ch	The character check for.

Return

The number of times ch occurs in str.

Declaration

public static int countOccurences(String str, int ch) 

Method Source Code

//package com.java2s;
/*//  ww w  .  j  a  v a  2s .  c o m
 * Copyright (C) 2001-2003 Colin Bell
 * colbell@users.sourceforge.net
 *
 * This library 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 2.1 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

public class Main {
    /**
     * Return the number of occurences of a character in a string.
     *
     * @param str   The string to check.
     * @param ch   The character check for.
     *
     * @return   The number of times <tt>ch</tt> occurs in <tt>str</tt>.
     */
    public static int countOccurences(String str, int ch) {
        if (isEmpty(str)) {
            return 0;
        }

        int count = 0;
        int idx = -1;
        do {
            idx = str.indexOf(ch, ++idx);
            if (idx != -1) {
                ++count;
            }
        } while (idx != -1);
        return count;
    }

    /**
     * Return <tt>true</tt> if the passed string is <tt>null</tt> or empty.
     *
     * @param   str      String to be tested.
     *
     * @return   <tt>true</tt> if the passed string is <tt>null</tt> or empty.
     */
    public static boolean isEmpty(String str) {
        return str == null || str.length() == 0;
    }
}

Related

1. countOccurence(String matchedString, char occurence)
2. countOccurences(String from, String word)
3. countOccurences(String haystack, String needle)
4. countOccurences(String s, char c)
5. countOccurences(String str, String subStr)
6. countOccurences(String text, char find)
7. countOccurences(String text, String subtext)
8. countOccurences(String text, String target)