package com.foxinmy.weixin4j.pay.sign;
   
   import com.foxinmy.weixin4j.exception.WeixinException;
   import com.foxinmy.weixin4j.pay.type.SignType;
   import com.foxinmy.weixin4j.util.DigestUtil;
   
   import java.security.InvalidKeyException;
   
   /**
   * 微信支付签名实现
   *
   * @className WeixinPaymentSignature
   * @author jinyu(foxinmy@gmail.com)
   * @date 2016年3月26日
   * @since JDK 1.6
   * @see <a
   *      href="https://pay.weixin.qq.com/wiki/doc/api/external/jsapi.php?chapter=4_3">支付签名说明</a>
   */
  public class WeixinPaymentSignature extends AbstractWeixinSignature {
  	/**
  	 * 支付密钥
  	 */
  	private final String paySignKey;
  
  	public WeixinPaymentSignature(String paySignKey) {
  		this.paySignKey = paySignKey;
  	}
  
  	@Override
  	public String sign(Object obj) {
  		StringBuilder sb = join(obj).append("&key=").append(paySignKey);
  		return DigestUtil.MD5(sb.toString()).toUpperCase();
  	}
  
  	@Override
  	public String sign(Object obj, SignType signType) {
  		if(signType==null){
  			return sign(obj);
  		}
  		switch (signType){
  			case HMAC$SHA256:
  				StringBuilder sb = join(obj).append("&key=").append(paySignKey);
  				try {
  					return DigestUtil.HMACSHA256(sb.toString(), paySignKey).toUpperCase();
  				}catch (InvalidKeyException e){
  					throw new RuntimeException("商户支付密钥有误", e);
  				}
  			default:
  				return sign(obj);
  		}
  	}
  }