Java String getDigits() Utility Method

Java String Utility Methods


This page contains the source code of Java String getDigits() utility method - This method checks if a String contains Unicode digits, if yes then concatenate all the digits in and return it as a String.

Java String getDigits() Utility Method

The following String getDigits() utility method checks if a String contains Unicode digits, if yes then concatenate all the digits in and return it as a String:
/**
 * <p>
 * Checks if a String {@code str} contains Unicode digits, if yes then
 * concatenate all the digits in {@code str} and return it as a String.
 * </p>
 *
 * <p>
 * An empty ("") String will be returned if no digits found in {@code str}.
 * </p>
 * 
 * @param str
 *            the String to extract digits from, may be null
 * @return String with only digits, or an empty ("") String if no digits
 *         found, or {@code null} String if {@code str} is null
 * @since 3.6
 */
public static String getDigits(final String str) {
    if (isEmpty(str)) {
        return str;
    }
    final int sz = str.length();
    final StringBuilder strDigits = new StringBuilder(sz);
    for (int i = 0; i < sz; i++) {
        final char tempChar = str.charAt(i);
        if (Character.isDigit(tempChar)) {
            strDigits.append(tempChar);
        }
    }
    return strDigits.toString();
}




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