微信支付-微信红包Java版本

 * 红包对象
 * @author 小帅帅丶
 * @date  2016-8-17上午11:12:19
 * @开源中国  http://my.oschina.net/xshuai
 */
public class RedPack implements Serializable{
	private String sign; //根据属性生成的验证
	private String mch_billno; //订单号
	private String mch_id;  //商户号
	private String wxappid; // 微信appid
	private String send_name;// 商户名称
	private String re_openid;// 用户openid
	private String total_amount;// 付款金额
	private String total_num;//红包接收人数  现金红包只能是  1
	private String wishing;// 红包祝福语
	private String client_ip;// 调用接口机器的IP
	private String act_name;// 活动名称
	private String remark;// 备注
	private String nonce_str;// 随机字符串
        //set  get省略
}

/**
 * 红包工具类
 * @author 小帅帅丶
 * @date  2016-8-17上午11:12:19
 * @开源中国  http://my.oschina.net/xshuai
 */
public class RedPackUtil {
	/**
	 * 生成商户订单号
	 * @param mch_id  商户号
	 * @param userId  该用户的userID
	 * @return
	 */
	public static String createBillNo(){
		//组成： mch_id+yyyymmdd+10位一天内不能重复的数字
		//10位一天内不能重复的数字实现方法如下:
		//因为每个用户绑定了userId,他们的userId不同,加上随机生成的(10-length(userId))可保证这10位数字不一样
		Date dt=new Date();
		SimpleDateFormat df = new SimpleDateFormat("yyyymmdd");
		String nowTime= df.format(dt);
		int length = 10 ;
		return WXConstants.MCH_ID + nowTime  + getRandomNum(length);
	}
	/**
	 * 生成特定位数的随机数字
	 * @param length
	 * @return
	 */
	public static String getRandomNum(int length) {
		String val = "";
		Random random = new Random();
		for (int i = 0; i < length; i++) {
			val += String.valueOf(random.nextInt(10));
		}
		return val;
	}
}

RedPack pack = new RedPack(null//第一次为空, RedPackUtil.createBillNo()//商户订单号,
				"你自己的商户号", "公众号的appid", "名称",
				"要发送用户的openid", "发送金额 单位是分 例如100 则是1元RMB", "只能是1", "9", "127.0.0.1",
				"活动名称", "备注", "随机字符串");

String signs = Signature.getSign(pack);
//生成的signset到pack对象中
pack.setSign(signs);
//将对象转为xml格式 微信要求xml格式
String xml = XmlUtil.objToXml(pack,RedPack.class,"xml");

public class RedPackService{
	/**
	 * 红包接口地址
	 */
	private  final static  String REDP_ORDER_PATH="https://api.mch.weixin.qq.com/mmpaymkttransfers/sendredpack";
	/**
	 * 红包
	 * 需要证书
	 * @param paramXml
	 * @return
	 */
	public static String redpackOrder(String paramXml){
		try {
			
			WXBaseService service=new WXBaseService(REDP_ORDER_PATH);
		
			return service.sendPost(paramXml);
			
		} catch (Exception e) {
			
			log.error(e.toString());
		} 
		return null;
	}
}

    /**
     * 通过Https往API post xml数据
     *
     * @param url    API地址
     * @param xmlObj 要提交的XML数据对象
     * @return API回包的实际数据
     * @throws IOException
     * @throws KeyStoreException
     * @throws UnrecoverableKeyException
     * @throws NoSuchAlgorithmException
     * @throws KeyManagementException
     */

    public String sendPost(String url, String postDataXML) throws IOException, KeyStoreException, UnrecoverableKeyException, NoSuchAlgorithmException, KeyManagementException {

        if (!hasInit) {
            init();
        }

        String result = null;

        HttpPost httpPost = new HttpPost(url);

        //解决XStream对出现双下划线的bug
//        XStream xStreamForRequestPostData = new XStream(new DomDriver("UTF-8", new XmlFriendlyNameCoder("-_", "_")));

        //将要提交给API的数据对象转换成XML格式数据Post给API
//        String postDataXML = xStreamForRequestPostData.toXML(xmlObj);

        Util.log("API，POST过去的数据是：");
        Util.log(postDataXML);

        //得指明使用UTF-8编码，否则到API服务器XML的中文不能被成功识别
        StringEntity postEntity = new StringEntity(postDataXML, "UTF-8");
        httpPost.addHeader("Content-Type", "text/xml");
        httpPost.setEntity(postEntity);

        //设置请求器的配置
        httpPost.setConfig(requestConfig);

        Util.log("executing request" + httpPost.getRequestLine());

        try {
            HttpResponse response = httpClient.execute(httpPost);

            HttpEntity entity = response.getEntity();

            result = EntityUtils.toString(entity, "UTF-8");

        } catch (ConnectionPoolTimeoutException e) {
            log.e("http get throw ConnectionPoolTimeoutException(wait time out)");

        } catch (ConnectTimeoutException e) {
            log.e("http get throw ConnectTimeoutException");

        } catch (SocketTimeoutException e) {
            log.e("http get throw SocketTimeoutException");

        } catch (Exception e) {
            log.e("http get throw Exception");

        } finally {
            httpPost.abort();
        }

        return result;
    }

<xml>
<return_code><![CDATA[SUCCESS]]></return_code>
<return_msg><![CDATA[帐号余额不足，请到商户平台充值后再重试]]></return_msg>
<result_code><![CDATA[FAIL]]></result_code>
<err_code><![CDATA[NOTENOUGH]]></err_code>
<err_code_des><![CDATA[帐号余额不足，请到商户平台充值后再重试]]></err_code_des>
<mch_billno><![CDATA[1371729102201629220149762756]]></mch_billno>
<mch_id><![CDATA[这里是商户号为了保密删除了]]></mch_id>
<wxappid><![CDATA[微信公众号appid]]></wxappid>
<re_openid><![CDATA[od5qQw8E_LbiAW9sZzuD-2xHtmvx这个是用户的openid]]></re_openid>
<total_amount>100</total_amount>
</xml>