调用微信Js-SDK图片

1.Js代码：

$(document).ready(function(){
　　 var url = location.href.split('#')[0];
　　 var imgSrc = "";
    $.get(rootPath + "/wechat/getWechatConfig?url=" + url,"",function(data){
        wx.config({
            debug: false,
            appId: data.appId,
            nonceStr: data.nonceStr,
            signature: data.signature,
            timestamp: parseInt(data.timestamp),
            jsApiList: [
                'checkJsApi',
                'onMenuShareTimeline',
                'onMenuShareAppMessage',
                'onMenuShareQQ',
                'onMenuShareWeibo',
                'hideMenuItems',
                'showMenuItems',
                'hideAllNonBaseMenuItem',
                'showAllNonBaseMenuItem',
                'translateVoice',
                'startRecord',
                'stopRecord',
                'onRecordEnd',
                'playVoice',
                'pauseVoice',
                'stopVoice',
                'uploadVoice',
                'downloadVoice',
                'chooseImage',
                'previewImage',
                'uploadImage',
                'downloadImage',
                'getNetworkType',
                'openLocation',
                'getLocation',
                'hideOptionMenu',
                'showOptionMenu',
                'closeWindow',
                'scanQRCode',
                'chooseWXPay',
                'openProductSpecificView',
                'addCard',
                'chooseCard',
                'openCard'
            ]
        });
    });

   
    wx.ready(function () {
        /**
         * 选择图片
         */
        document.querySelector('#id').onclick = function () {
            wx.chooseImage({
              count: 1, // 可选择图片张数
              success: function (res) {
                //alert("选择成功：" + res.localIds);
                setTimeout(function(){ 
                    wx.uploadImage({
                        localId: res.localIds.toString(),
                        isShowProgressTips:1,
                        success : function(res){
                            //alert("上传成功" + res.serverId);
                            //上传成功后，图片在微信服务器保存7天，接下来将图片下载到自己服务器返回地址，格式如http://app.baidu.com/map/images/tiananmen.jpg，供图片预览
　　　　　　　　　　　　　　　　$.get("/wechat/saveImg?mediaId=" + res.serverId.toString(),"",function(result){
                                if(result == ""){
                                    alert("下载失败");
                                }else{
                                    imgSrc = result;
                                }
                            });
                        },
                        fail: function(res){
                            alert("上传失败" + res.errMsg);
                        }
                    });
                },100);
              }
            });
        }
    
        /**
         * 预览图片
         */
        document.querySelector('#id').onclick = function () {
            wx.previewImage({
                current: imgSrc, 
                urls: [imgSrc]
            });
        }
        
        //微信地图
        document.querySelector('#mapBtn').onclick = function () {
            wx.getLocation({
                success: function (res) {
                    var longitude = res.longitude; // 纬度，浮点数，范围为90 ~ -90
                    var latitude = res.latitude; // 经度，浮点数，范围为180 ~ -180。
                    var speed = res.speed; // 速度，以米/每秒计
                    var accuracy = res.accuracy; // 位置精度
                    //alert("纬度:" + longitude +"---"+ "经度:" + latitude  +"---"+ "速度:" + speed  +"---"+ "位置:" + accuracy);
                    wx.openLocation({
                        latitude: latitude,
                        longitude: longitude,
                        name: '我的位置',
                        address: accuracy,
                        scale: speed,
                        infoUrl: 'http://weixin.qq.com'
                    });
                },
                cancel: function (res) {
                    alert('取消获取地理位置');
                }
            });
        };    
    });

    wx.error(function (res) {
        alert(res.errMsg);
    });
      
});

//获取微信配置wx.config使用
public static WechatConfig getWechatConfig(String url) throws Exception {
        System.out.println(UPLOAD_IMAGE_PATH);
        WechatConfig config = new WechatConfig();
        config.setAppId(APPID);
        String nonceStr = UUID.randomUUID().toString().replaceAll("-", "");
        config.setNonceStr(nonceStr);
        String timestamp = Long.toString(System.currentTimeMillis() / 1000);
        config.setTimestamp(timestamp);
        String str = "jsapi_ticket=" + getJsapiTicket().getTicket()
                + "&noncestr=" + nonceStr + "&timestamp=" + timestamp + "&url="
                + url;

        MessageDigest crypt = MessageDigest.getInstance("SHA-1");
        crypt.reset();
        crypt.update(str.getBytes("UTF-8"));
        String signature = byteToHex(crypt.digest());
        config.setSignature(signature);
        logger.info("wechatConfig:" + JsonMapper.toJsonString(config));
        return config;
    }


public static JsapiTicket getJsapiTicket() throws Exception {
        JsapiTicket jsapiTicket = new JsapiTicket();
        String url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?access_token=ACCESS_TOKEN&type=jsapi";
        logger.info("获取JsapiTicket开始：");
        JSONObject jsonObject = doGetStr(url);
        if (jsonObject != null) {
            jsapiTicket.setErrcode(jsonObject.getString("errcode"));
            jsapiTicket.setErrmsg(jsonObject.getString("errmsg"));
            jsapiTicket.setExpiresIn(jsonObject.getString("expires_in"));
            jsapiTicket.setTicket(jsonObject.getString("ticket"));
        }
        logger.info(JsonMapper.toJsonString(jsapiTicket));
        return jsapiTicket;
    }

private static String byteToHex(final byte[] hash) {
        Formatter formatter = new Formatter();
        for (byte b : hash) {
            formatter.format("%02x", b);
        }
        String result = formatter.toString();
        formatter.close();
        return result;
    }

public static JSONObject doGetStr(String url) throws ParseException,
            IOException {
        DefaultHttpClient client = new DefaultHttpClient();
        HttpGet httpGet = new HttpGet(url);
        JSONObject jsonObject = null;
        HttpResponse httpResponse = client.execute(httpGet);
        HttpEntity entity = httpResponse.getEntity();
        if (entity != null) {
            String result = EntityUtils.toString(entity, "UTF-8");
            EntityUtils.consume(entity);
            jsonObject = JSONObject.parseObject(result);
        }
        return jsonObject;
    }

    /**
     * 从微信服务器下载,再上传到图片服务器
     * 
     * @return
     * @throws Exception
     */
    public static String saveImg(String mediaId) throws Exception {
        String url = "http://file.api.weixin.qq.com/cgi-bin/media/get?access_token=ACCESS_TOKEN&media_id=MEDIA_ID";
        logger.info("从微信服务器下载开始……");
        logger.info(url);
        DefaultHttpClient client = new DefaultHttpClient();
        HttpGet httpGet = new HttpGet(url);
        JSONObject jsonObject = null;
        HttpResponse httpResponse = client.execute(httpGet);
        if (httpResponse.getStatusLine().getStatusCode() != 200) {
            logger.info("从微信服务器下载失败："
                    + httpResponse.getStatusLine().getStatusCode());
            return "";
        }

        String fileName = "";
        String str = httpResponse.getFirstHeader("Content-disposition")
                .getValue();
        if (StringUtils.isNotEmpty(str) && str.indexOf(""") != -1) {
            fileName = str.substring(str.indexOf(""") + 1,
                    str.lastIndexOf("""));
            logger.info("从微信服务器下载成功：" + fileName);
        }
        String dateStr = "/upload/" + new SimpleDateFormat("yyyyMMdd").format(new Date());
        String path = "/usr/local/tomcat7/webapps" + dateStr;
        
        File file = new File(path);
        if(!file.exists())
            file.mkdirs();
        logger.info("保存的图片路径：" + path);
        
        HttpEntity entity = httpResponse.getEntity();
        InputStream is = null;
        FileOutputStream fos = null;
        ByteArrayOutputStream bos = null;
        try {
            is = entity.getContent();
            bos = new ByteArrayOutputStream(); 
            byte[] buffer = new byte[1024];
            int len = 0;  
            while( (len=is.read(buffer)) != -1 ){  
                bos.write(buffer, 0, len);  
            }
            fos = new FileOutputStream(path + "/" + fileName);
            fos.write(bos.toByteArray());
        } catch (Exception e) {
            logger.info("保存到图片服务器失败：" + e.fillInStackTrace());
            e.printStackTrace();
            return "";
        }finally{  
            is.close();  
            fos.close();  
        } 
        return PREVIEW_IMAGE_URL + dateStr + "/" + fileName;
    }