微信公众号开发获取 access_token，Signature， jsapi_ticket ----java

微信公众号开发进行 给前端进行授权返回信息
注意：url是动态获取，就是你请求支付页面的完整路径

//这里的url是动态获取，就是你请求支付页面的完整路径  可以i自己获取 也可以是前端传过来的

//获取 Signature
	@SuppressWarnings("unchecked")
	public  String getSignature(String nonceStr, String timestamp, String url) {
	    String signature = "";
	    String appid =WXConfig.getAppid();//微信公众号的appid
	    String appsecret =WXConfig.getAppsecret();//微信公众号的appsecret
	    //获取noncestr 
	    String noncestr = nonceStr;
	    //获取timestamp
	    //String timestamp = timestamp ;
	    //获取access_token
	    access_token = WXConfig.getAccessToken(appid , appsecret);
	    //获取jsapi_ticket
	    jsapi_ticket = WXConfig.getTicket(access_token);
	    //将四个数据进行组合，传给SHA1进行加密
	    
	    String str = "jsapi_ticket=" + jsapi_ticket +
	            "&noncestr=" + noncestr +
	            "×tamp=" + timestamp +
	            "&url=" + url;
	    System.out.println(str);
	    //SHA1加密
	    signature = WXConfig.SHA1(str);
	    return signature ;
	}
	
	//先获取access_token
	public static String getAccessToken(String appId , String appSecret){
	    // 网页授权接口
	    String GetPageAccessTokenUrl = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid="+appId+"&secret="+appSecret;
	    //https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=wx1ac1da6bd53d08c3&secret=905b123c21f243cd45581b249076d893;
	 
	    HttpClient client = null;
	    String access_token = null;
	    int expires_in = 0;
	    try {
	        client = new DefaultHttpClient();
	        HttpGet httpget = new HttpGet(GetPageAccessTokenUrl);
	        ResponseHandler<String> responseHandler = new BasicResponseHandler();
	        String response = client.execute(httpget, responseHandler);
	        JSONObject OpenidJSONO = JSONObject.fromObject(response);
	        access_token = String.valueOf(OpenidJSONO.get("access_token"));//获取access_token 
	        expires_in = Integer.parseInt(String.valueOf(OpenidJSONO.get("expires_in")));//获取时间
	    } catch (Exception e) {
	        //throw new CommonRuntimeException("获取AccessToken出错！");
	    	System.out.println("获取AccessToken出错！");
	    } finally {
	        client.getConnectionManager().shutdown();
	    }
	    return access_token;
	}
	
	//获取jsapi_ticket
	public static String getTicket(String accessToken) {
	    // 网页授权接口
	   String GetPageAccessTokenUrl = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?access_token="+accessToken+"&type=jsapi";
	    HttpClient client = null;
	    String ticket = "";
	    int expires_in = 0;
	    try {
	        client = new DefaultHttpClient();
	        HttpGet httpget = new HttpGet(GetPageAccessTokenUrl);
	        ResponseHandler<String> responseHandler = new BasicResponseHandler();
	        String response = client.execute(httpget, responseHandler);
	        JSONObject OpenidJSONO = JSONObject.fromObject(response);
	        ticket = String.valueOf(OpenidJSONO.get("ticket"));//获取ticket
	        expires_in = Integer.parseInt(String.valueOf(OpenidJSONO.get("expires_in")));//获取时间
	    } catch (Exception e) {
	        //throw new CommonRuntimeException("获取Ticket出错！");
	    	System.out.println("获取Ticket出错！");
	    } finally {
	        client.getConnectionManager().shutdown();
	    }
	    return ticket;
	}
	
	//SHA1加密，参数是由url、jsapi_ticket、noncestr、timestamp组合而成
	public static String SHA1(String str) {
	    try {
	        MessageDigest digest = java.security.MessageDigest
	                .getInstance("SHA-1"); //如果是SHA加密只需要将"SHA-1"改成"SHA"即可
	        digest.update(str.getBytes());
	        byte messageDigest[] = digest.digest();
	        // Create Hex String
	        StringBuffer hexStr = new StringBuffer();
	        // 字节数组转换为 十六进制 数
	        for (int i = 0; i < messageDigest.length; i++) {
	            String shaHex = Integer.toHexString(messageDigest[i] & 0xFF);
	            if (shaHex.length() < 2) {
	                hexStr.append(0);
	            }
	            hexStr.append(shaHex);
	        }
	        return hexStr.toString();
	    } catch (NoSuchAlgorithmException e) {
	        e.printStackTrace();
	    }
	    return null;
	}

这就是获取access_token，Signature， jsapi_ticket