Java String countMatches() Utility Method - Check Count for Character in a String

This page contains the source code of the Java String countMatches() utility method - This method counts how many times the char appears in the given string.

This Utility method is very useful if you want to count how many times a given character appears in the given String.
 Java String countMatches() Utility Method
The following String countMatches() utility method counts how many times the char appears in the given string:
/**
  * <p>
  * Counts how many times the char appears in the given string.
  * </p>
  *
  * <p>
  * A {@code null} or empty ("") String input returns {@code 0}.
  * </p>
  * 
  * @param str
  *            the CharSequence to check, may be null
  * @param ch
  *            the char to count
  * @return the number of occurrences, 0 if the CharSequence is {@code null}
  * @since 3.4
  */
 public static int countMatches(final CharSequence str, final char ch) {
     if (isEmpty(str)) {
         return 0;
     }
     int count = 0;
     // We could also call str.toCharArray() for faster look ups but that
     // would generate more garbage.
     for (int i = 0; i < str.length(); i++) {
         if (ch == str.charAt(i)) {
             count++;
         }
     }
     return count;
 }
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