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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