java实现扫描小程序码跳转相应界面

古城微笑少年丶 2022-01-05 09:11 241阅读 0赞

我现在的业务需求是，扫二维码实现跳转到小程序的摸个界面，应该是用到的场景会很多，希望此篇博客帮助到大家！

1.  可以参照官方文档：  
    [https://developers.weixin.qq.com/miniprogram/dev/api-backend/open-api/qr-code/wxacode.getUnlimited.html\#HTTPS 调用][https_developers.weixin.qq.com_miniprogram_dev_api-backend_open-api_qr-code_wxacode.getUnlimited.html_HTTPS]
2.  首先需要获取token,这个可以参照：[https://developers.weixin.qq.com/miniprogram/dev/api-backend/open-api/access-token/auth.getAccessToken.html][https_developers.weixin.qq.com_miniprogram_dev_api-backend_open-api_access-token_auth.getAccessToken.html]
3.  设置生成二维码需要的参数：

Map<String, Object> param = new HashMap<>();
    		param.put("scene", “参数”); // 参数
    		param.put("page", "页面路径"); // 位置
    		param.put("width", 780);

1.  通过微信获取图片实现方法：

CloseableHttpClient httpClient = HttpClientBuilder.create().build();
    		HttpPost httpPost = new HttpPost("https://api.weixin.qq.com/wxa/getwxacodeunlimit?access_token=" + token); // 接口
    		httpPost.addHeader(HTTP.CONTENT_TYPE, "application/json");
    		String body = JSON.toJSONString(param); // 必须是json模式的 post
    		StringEntity entity;
    		entity = new StringEntity(body);
    		entity.setContentType("image/png");
    		httpPost.setEntity(entity);
    		HttpResponse response;
    		response = httpClient.execute(httpPost);

1.  处理图片

InputStream inputStream = response.getEntity().getContent();
    		String name = reserveOne + ".png";
    		String path = "C:/miniPic/qrcoude/";
    		String picPath =path + name;
    		File dir = new File(path, name);// 在目录中创建文件目录
    		if (!dir.getParentFile().exists()) { 
    			dir.getParentFile().mkdirs();// 创建文件
    		}
    		saveToImgByInputStream(inputStream, path, name); // 保存图片
    		
    		MultipartFile file = getMulFileByPath(picPath);
    		try { 
    			byte[] bytes = file.getBytes();
    			for(byte b : bytes){ 
    				System.out.print(b);
    			}
    		} catch (IOException e) { 
    			e.printStackTrace();
    		}
    		//此处为上传腾讯云存储的路径
    		String url = OSSFactory.build().upload(file);
            return url;

1.  所需的一些工具类

public int saveToImgByInputStream(InputStream instreams, String imgPath, String imgName) { 
    		int stateInt = 1;
    		if (instreams != null) { 
    			try { 
    				File files=new File(imgPath);    
    				if  (!files .exists()  && !files .isDirectory())      
    				{         
    				    files .mkdir();    
    				} 
    				File file = new File(imgPath, imgName);// 可以是任何图片格式.jpg,.png等
    				FileOutputStream fos = new FileOutputStream(file);
    				byte[] b = new byte[1024];
    				int nRead = 0;
    				while ((nRead = instreams.read(b)) != -1) { 
    					fos.write(b, 0, nRead);
    				}
    				fos.flush();
    				fos.close();
    			} catch (Exception e) { 
    				stateInt = 0;
    				e.printStackTrace();
    			} finally { 
    			}
    		}
    		return stateInt;
    	}
    	private static MultipartFile getMulFileByPath(String picPath) { 
    		FileItem fileItem = createFileItem(picPath);
    		MultipartFile mfile = new CommonsMultipartFile(fileItem);
    		return mfile;
    	}
    	private static FileItem createFileItem(String filePath)
        { 
            FileItemFactory factory = new DiskFileItemFactory(16, null);
            String textFieldName = "textField";
            int num = filePath.lastIndexOf(".");
            String extFile = filePath.substring(num);
            FileItem item = factory.createItem(textFieldName, "text/plain", true,
                "MyFileName" + extFile);
            File newfile = new File(filePath);
            int bytesRead = 0;
            byte[] buffer = new byte[8192];
            try
            { 
                FileInputStream fis = new FileInputStream(newfile);
                OutputStream os = item.getOutputStream();
                while ((bytesRead = fis.read(buffer, 0, 8192))
                    != -1)
                { 
                    os.write(buffer, 0, bytesRead);
                }
                os.close();
                fis.close();
            }
            catch (IOException e)
            { 
                e.printStackTrace();
            }
            return item;
        }

希望此篇文章可以帮助到大家哦！！！！

[https_developers.weixin.qq.com_miniprogram_dev_api-backend_open-api_qr-code_wxacode.getUnlimited.html_HTTPS]: https://developers.weixin.qq.com/miniprogram/dev/api-backend/open-api/qr-code/wxacode.getUnlimited.html#HTTPS%20%E8%B0%83%E7%94%A8
[https_developers.weixin.qq.com_miniprogram_dev_api-backend_open-api_access-token_auth.getAccessToken.html]: https://developers.weixin.qq.com/miniprogram/dev/api-backend/open-api/access-token/auth.getAccessToken.html