优化字符串处理：探索Java 21中StringBuilder和StringBuffer的全新repeat方法

/**
 * @throws IllegalArgumentException {@inheritDoc}
 *
 * @since 21
 */
@Override
public StringBuilder repeat(int codePoint, int count) {
    super.repeat(codePoint, count);
    return this;
}
/**
 * @throws IllegalArgumentException {@inheritDoc}
 *
 * @since 21
 */
@Override
public StringBuilder repeat(CharSequence cs, int count) {
    super.repeat(cs, count);
    return this;
}

var sb = new StringBuilder().repeat("*", 10);
System.out.println(sb);