Java生成微信微信小程序太阳码，解决图片错误问题

梦里梦外; 2023-05-22 04:54 13阅读 0赞

[二维码生成链接][Link 1]  
如需依赖也是在上边这个链接里  
1.GetTokenUtil类  
获取Token

import com.alibaba.fastjson.JSONObject;
    
    import java.io.BufferedReader;
    import java.io.IOException;
    import java.io.InputStreamReader;
    import java.io.PrintWriter;
    import java.net.URL;
    import java.net.URLConnection;
    import java.util.Iterator;
    import java.util.LinkedHashMap;
    import java.util.Map;
    
    public class GetTokenUtil { 
        /** * 向指定 URL 发送POST方法的请求 * * @param url 发送请求的 URL * @return 所代表远程资源的响应结果 */
        public static String sendPost(String url, Map<String, ?> paramMap) { 
            PrintWriter out = null;
            BufferedReader in = null;
            String result = "";
            String param = "";
            Iterator<String> it = paramMap.keySet().iterator();
            while (it.hasNext()) { 
                String key = it.next();
                param += key + "=" + paramMap.get(key) + "&";
            }
            try { 
                URL realUrl = new URL(url);
                // 打开和URL之间的连接
                URLConnection conn = realUrl.openConnection();
                // 设置通用的请求属性
                conn.setRequestProperty("accept", "*/*");
                conn.setRequestProperty("connection", "Keep-Alive");
                conn.setRequestProperty("Accept-Charset", "utf-8");
                conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
                // 发送POST请求必须设置如下两行 作者qq:1023732997
                conn.setDoOutput(true);
                conn.setDoInput(true);
                // 获取URLConnection对象对应的输出流
                out = new PrintWriter(conn.getOutputStream());
                // 发送请求参数
                out.print(param);
                // flush输出流的缓冲
                out.flush();
                // 定义BufferedReader输入流来读取URL的响应
                in = new BufferedReader(new InputStreamReader(conn.getInputStream(), "UTF-8"));
                String line;
                while ((line = in.readLine()) != null) { 
                    result += line;
                }
            } catch (Exception e) { 
                System.out.println(e);
            }
            // 使用finally块来关闭输出流、输入流
            finally { 
                try { 
                    if (out != null) { 
                        out.close();
                    }
                    if (in != null) { 
                        in.close();
                    }
                } catch (IOException ex) { 
                    ex.printStackTrace();
                }
            }
            return result;
        }
    
        public static String getToken() { 
            try { 
                Map<String, String> map = new LinkedHashMap<String, String>();
                map.put("grant_type", "client_credential");
                map.put("appid", MiniProgram.APP_ID);// 这里我是写在配置类里，需要改成自己的appid
                map.put("secret", MiniProgram.APP_secret); //这里我是写在配置类里，需要改成自己的secret
                String rt = GetTokenUtil.sendPost("https://api.weixin.qq.com/cgi-bin/token", map);
                JSONObject json = JSONObject.parseObject(rt);
                if (json.getString("access_token") != null || json.getString("access_token") != "") { 
    // System.out.println("token:" + json.getString("access_token"));
                    return json.getString("access_token");
                } else { 
                    return null;
                }
            } catch (Exception e) { 
                e.printStackTrace();
                return null;
            }
    
        }
    
    }

2.测试类  
paramJson.put(“page”, “pages/index”);这里在小程序未发布前需要注释，否则找不到对应的页面，就会生成错误

import org.json.JSONObject;
    
    import javax.imageio.ImageIO;
    import java.awt.image.BufferedImage;
    import java.io.*;
    import java.net.HttpURLConnection;
    import java.net.URL;
    
    public class QR { 
        public static void main(String[] args) { 
            try { 
                URL url = new URL("https://api.weixin.qq.com/wxa/getwxacodeunlimit?access_token=" + GetTokenUtil.getToken());
                System.out.println(url);
                HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
                httpURLConnection.setRequestMethod("POST");// 提交模式
                // conn.setConnectTimeout(10000);//连接超时 单位毫秒
                // conn.setReadTimeout(2000);//读取超时 单位毫秒
                // 发送POST请求必须设置如下两行
                httpURLConnection.setDoOutput(true);
                httpURLConnection.setDoInput(true);
                // 获取URLConnection对象对应的输出流
                PrintWriter printWriter = new PrintWriter(httpURLConnection.getOutputStream());
                // 发送请求参数
                JSONObject paramJson = new JSONObject();
                paramJson.put("scene", "1234567890");//参数
                //paramJson.put("page", "pages/index");//小程序未发布前注释，否则找不到对应的页面，就会生成错误的图片
                paramJson.put("width", 430);
    // paramJson.put("auto_color", true);
    // paramJson.put("auto_color", false);
                JSONObject lineColor = new JSONObject();
                lineColor.put("r", 0);
                lineColor.put("g", 0);
                lineColor.put("b", 0);
                paramJson.put("line_color", lineColor);
                printWriter.write(paramJson.toString());
                // flush输出流的缓冲
                printWriter.flush();
                //开始获取数据
                BufferedInputStream bis = new BufferedInputStream(httpURLConnection.getInputStream());
                OutputStream os = new FileOutputStream(new File("D:\\云上\\tym.png"));
                BufferedImage read = ImageIO.read(httpURLConnection.getInputStream());
                if (read == null) { 
                    System.out.println("null");
                } else { 
                    ImageIO.write(read, "png", new File("D:\\云上\\tym1.png"));
                }
                int len;
                byte[] arr = new byte[1024];
                while ((len = bis.read(arr)) != -1) { 
                    os.write(arr, 0, len);
                    os.flush();
                }
                os.close();
            } catch (Exception e) { 
                e.printStackTrace();
            }
        }
    
    }

3.效果图  
带参数的比如pages/index?id=‘12345’  
扫码后需要前端解析scene  
搜索 闲益小区 小程序了解更多或者扫描太阳码  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwNjE4NjY0_size_16_color_FFFFFF_t_70_pic_center]

[Link 1]: https://blog.csdn.net/qq_40618664/article/details/105551360
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwNjE4NjY0_size_16_color_FFFFFF_t_70_pic_center]: /images/20230521/49cbfd6025b84a57bec2c5cf2c473d35.png