合并任意个数组生成一个新的数组

/**
 * 合并任意个数组
 * @param first
 * @param rest
 * @param <T>
 * @return
 */
public static <T> T[] concat(T[] first, T[]... rest) {
    int totalLength = first.length;
    for (T[] array : rest) {
        totalLength += array.length;
    }
    T[] result = java.util.Arrays.copyOf(first, totalLength);
    int offset = first.length;
    for (T[] array : rest) {
        System.arraycopy(array, 0, result, offset, array.length);
        offset += array.length;
    }
    return result;
}