工具方法

System.getProperty("user.dir")
+ System.getProperty("file.separator")

public static String amtLee2Yuan(String amt_pay) {
        int scale = 2;
        BigDecimal b1 = new BigDecimal(amt_pay);
        BigDecimal b2 = new BigDecimal(1000);
        return b1.divide(b2, scale, BigDecimal.ROUND_FLOOR).toPlainString();
    }

public enum TransCodeEnum {

    singlePay("022C"),
    singleQuery("0228");

    String code;

    private TransCodeEnum(String code) {
        this.code = code;
    }

    public String getCode() {
        return this.code;
    }
}

/**
     * 为指定文本内容在前面添加“0”
     * 
     * @param content
     *            指定内容。
     * @param digit
     *            文本预置长度。
     * @return 补全空格后的文本。参数错误时返回<code>null</code>。
     */
    public static String lengthFilter(String content, int digit) {
        if (content == null) {
            content = "";
        }
        int len = content.length() - digit;
        if (len > 0) {
            logger.error("文本内容[content:" + content + ",len:" + content.length() + "]超过指定长度[len:" + digit + "]");
            return null;
        }
        StringBuffer res = new StringBuffer(digit);
        res.append(content);
        if (len < 0) {
            for (int i = 0; i < (-len); i++) {
                res.insert(0, "0");
            }
        }
        return res.toString();
    }

/**
     * 读文件
     * 
     * @param file
     * @return
     * @throws Exception
     */
    public static byte[] readFile(File file) {
        BufferedInputStream in = null;
        ByteArrayOutputStream out = null;
        try {
            in = new BufferedInputStream(new FileInputStream(file));
            out = new ByteArrayOutputStream();
            byte[] temp = new byte[1024];
            int size = 0;
            while ((size = in.read(temp)) != -1) {
                out.write(temp, 0, size);
            }
            return out.toByteArray();
        } catch (Exception e) {
        } finally {
            try {
                if (null != out)
                    out.close();
                if (null != in)
                    in.close();
            } catch (Exception e2) {
            }
        }
        return null;
    }

    /**
     * 补位
     * 
     * @param byte_array
     * @return
     */
    public static byte[] paddingByte(byte[] byte_array) {
        int length = byte_array.length;
        int mode = length % 8;
        int times = 0;
        if (mode != 0)
            times = 8 - mode;
        byte[] sendByte = new byte[length + times];
        for (int i = 0; i < length; i++) {
            sendByte[i] = byte_array[i];
        }
        for (int j = length; j < length + times; j++) {
            sendByte[j] = 0x00;
        }
        return sendByte;
    }