Java生成微信小程序二維碼完整實例代碼

更新時間：2025年09月11日 10:48:51 作者：.也許.

微信小程序是一種輕量級的應用程序,用戶無需下載安裝即可使用,因此受到了廣泛的歡迎,這篇文章主要介紹了Java生成微信小程序二維碼的相關(guān)資料,包含上傳圖片、參數(shù)傳遞及二維碼生成邏輯,詳細說明了各組件作用及使用方法,需要的朋友可以參考下

1. java 二維碼生成工具類

import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONObject;
import com.pdatao.api.controller.file.FileController;
import com.pdatao.api.error.CommunityException;
import org.apache.commons.io.IOUtils;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.web.multipart.MultipartFile;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.charset.StandardCharsets;

@Component
public class MpQrCodeUtil {

    @Resource
    FileController fileController;

    @Value("${mp.wechat.appid}")
    private String mpAppId;
    @Value("${mp.wechat.secret}")
    private String mpSecretId;

    @Value("${qrcode.pageHome}")
    private String pageHome;
    @Value("${spring.profiles.active:}")
    private String activeProfile;

    private static final String API_GET_TOKEN = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=%s&secret=%s";
    private static final String API_GET_QR_CODE = "https://api.weixin.qq.com/wxa/getwxacodeunlimit?access_token=%s";
    private static String cachedToken = null;
    private static long tokenExpireTime = 0;


    public String getMpQRCode(Long orderId, HttpServletRequest request) throws Exception {
        String scenes = "id=" + orderId + "&v=1";
        String envVersion = "";
        if ("prod-plus".equals(activeProfile)) {
            envVersion = "release";
        }
        return this.getQRCodeWeb(scenes,envVersion,orderId,request);
    }

    public String getQRCodeWeb(String scenes, String envVersion, Long orderId, HttpServletRequest request) throws Exception {
        String accessToken = getToken(mpAppId, mpSecretId);
        return getQRCode(accessToken, scenes, envVersion, orderId, request);
    }

    public static String getToken(String appId, String appSecret) throws Exception {
        // 1. 檢查緩存是否有效
        if (cachedToken != null && System.currentTimeMillis() < tokenExpireTime) {
            return cachedToken;
        }
        HttpURLConnection conn = null;

        try {
            String url = String.format(API_GET_TOKEN, appId, appSecret);
            conn = (HttpURLConnection) new URL(url).openConnection();
            conn.setConnectTimeout(5000);
            conn.setReadTimeout(5000);
            conn.setRequestMethod("GET");


            int statusCode = conn.getResponseCode();
            if (statusCode != 200) {
                // 讀取錯誤流
                String errorJson = IOUtils.toString(conn.getErrorStream(), StandardCharsets.UTF_8);
                throw new CommunityException("微信接口錯誤: " + errorJson);
            }


            JSONObject result = new JSONObject(IOUtils.toString(conn.getInputStream(), StandardCharsets.UTF_8));

            cachedToken = result.getStr("access_token");
            long expiresIn = result.getLong("expires_in") * 1000; // 轉(zhuǎn)為毫秒
            tokenExpireTime = System.currentTimeMillis() + expiresIn - 600_000;

            return cachedToken;

        } finally {
            if (conn != null) conn.disconnect();
        }
    }


    public String getQRCode(String accessToken, String scenes, String envVersion, Long orderId, HttpServletRequest request) throws Exception {
        HttpURLConnection httpURLConnection = null;
        try {
            URL url = new URL(String.format(API_GET_QR_CODE, accessToken));
            httpURLConnection = (HttpURLConnection) url.openConnection();
            httpURLConnection.setRequestMethod("POST");// 提交模式
            // 發(fā)送POST請求必須設置如下兩行
            httpURLConnection.setDoOutput(true);
            httpURLConnection.setDoInput(true);

            // 發(fā)送請求參數(shù)
            com.alibaba.fastjson.JSONObject paramJson = new com.alibaba.fastjson.JSONObject();
            paramJson.put("scene", scenes);
            paramJson.put("page", pageHome);
            paramJson.put("env_version", StrUtil.isNotEmpty(envVersion) ? envVersion : "trial");
            paramJson.put("check_path", false);

            try (PrintWriter printWriter = new PrintWriter(httpURLConnection.getOutputStream())) {
                printWriter.write(paramJson.toString());
                printWriter.flush();
            }

            // 檢查響應碼
            int responseCode = httpURLConnection.getResponseCode();
            if (responseCode != HttpURLConnection.HTTP_OK) {
                cachedToken = null;
                throw new CommunityException("生成二維碼失?。篐TTP錯誤碼 " + responseCode);
            }

            // 檢查內(nèi)容類型
            String contentType = httpURLConnection.getContentType();
            if (contentType == null || !contentType.startsWith("image/")) {
                cachedToken = null;
                throw new CommunityException("生成二維碼失?。航涌诜祷胤菆D片數(shù)據(jù)（" +  (contentType != null ? contentType : "未知內(nèi)容類型") + "）");
            }

            try (InputStream is = httpURLConnection.getInputStream(); ByteArrayOutputStream baos = new ByteArrayOutputStream();) {
                byte[] buffer = new byte[1024];
                int len = -1;
                while ((len = is.read(buffer)) != -1) {
                    baos.write(buffer, 0, len);
                }

                byte[] imageData = baos.toByteArray();

                // 簡單驗證是否是有效圖片（可選）
                if (imageData.length == 0) {
                    cachedToken = null;
                    throw new CommunityException("生成二維碼失?。悍祷乜請D片數(shù)據(jù)");
                }

                MultipartFile multipartFile = new ByteArrayMultipartFile(
                        orderId + "_mpqrcode",          // 表單字段名
                        orderId + "_mpqrcode.png",      // 文件名
                        "image/png",                  // 內(nèi)容類型
                        imageData                  // 內(nèi)容
                );
                com.alibaba.fastjson.JSONObject json = fileController.upload(multipartFile,request);
                if (json == null || !json.containsKey("url")) {
                    throw new CommunityException("上傳圖片失敗：響應數(shù)據(jù)異常");
                }
                return json.getString("url");
            }
        } catch (Exception e) {
            e.printStackTrace();
            throw new CommunityException("生成二維碼失?。?+e.getMessage());
        } finally {
            if (httpURLConnection != null) {
                httpURLConnection.disconnect();
            }
        }
    }



}

2. 部分可自行調(diào)整的代碼解釋

FileController：我自己的上傳圖片到服務器的類

mpAppId：小程序appid

mpSecretId：小程序 SecretId

pageHome：要跳轉(zhuǎn)的小程序的頁面地址（例如： ‘pages/userInfo/userInfoHome’）

activeProfile：我自己的判斷當前運行環(huán)境的配置（可以忽略）

@Resource
FileController fileController;

@Value("${mp.wechat.appid}")
private String mpAppId;
@Value("${mp.wechat.secret}")
private String mpSecretId;

@Value("${qrcode.pageHome}")
private String pageHome;
@Value("${spring.profiles.active:}")
private String activeProfile;

getMpQRCode 外部調(diào)用的方法，自定義自己需要傳入什么值

Long orderId ：這個是我為了生成二維碼路徑時攜帶的參數(shù)

HttpServletRequest request： 這個參數(shù)，和二維碼生成邏輯沒有任何關(guān)系，我這里使用只是因為上傳圖片的地方需要這個值，這個比較冗余

scenes：定義頁面地址攜帶什么參數(shù)

if ("prod-plus".equals(activeProfile)) {
    envVersion = "release";
}      這個是為了判斷生成什么環(huán)境的二維碼圖片（正式版/ 體驗版）

public String getMpQRCode(Long orderId, HttpServletRequest request) throws Exception {
    String scenes = "id=" + orderId + "&v=1";
    String envVersion = "";
    if ("prod-plus".equals(activeProfile)) {
        envVersion = "release";
    }
    return this.getQRCodeWeb(scenes,envVersion,orderId,request);
}

imageData ： 這個就是生成的二維碼圖片信息

下面的其他信息，都是為了把這個圖片的信息，上傳到自己項目中保存，最終返回圖片地址

byte[] imageData = baos.toByteArray();

// 簡單驗證是否是有效圖片（可選）
if (imageData.length == 0) {
    throw new CommunityException("生成核銷二維碼失?。悍祷乜請D片數(shù)據(jù)");
}

MultipartFile multipartFile = new ByteArrayMultipartFile(
        orderId + "_mpqrcode",          // 表單字段名
        orderId + "_mpqrcode.png",      // 文件名
        "image/png",                  // 內(nèi)容類型
        imageData                  // 內(nèi)容
);
com.alibaba.fastjson.JSONObject json = fileController.upload(multipartFile,request);
if (json == null || !json.containsKey("url")) {
    throw new CommunityException("上傳二維碼失敗：響應數(shù)據(jù)異常");
}
return json.getString("url");

3.小程序中獲取攜帶的參數(shù)

以我上述的參數(shù)為例：（微信小程序使用的 uniapp）

onLoad(option) {
			
			if (option.scene) {
				const scene = decodeURIComponent(option.scene);
				const params = this.parseSceneParams(scene);
                console.log(params.id)
                console.log(params.v)
			}

},

methods: {
    			parseSceneParams(scene) {
			    const params = {};
			    if (!scene) return params;
			 
			    const pairs = scene.split('&');
			    pairs.forEach(pair => {
			      const [key, value] = pair.split('=');
			      if (key) params[key] = value;
			    });
			    return params;
			  },
}