WxQrCoodTool
java请求目标系统返回二进制图片的接口,并返回给请求方二进行图片流
前端-->java后台(相当于中转)-->图片服务器后端
/** * 获取小程序二维码,如果调用成功，会直接返回图片二进制内容，如果请求失败，会返回 JSON 格式的数据,根据此解释,应该直接由前端生成,不用绕后台 * @return */ @RequestMapping(value = {"/getWxACodeUnlimit"}, method = {RequestMethod.POST, RequestMethod.GET}) @ResponseBody @Override public void getWxACodeUnlimit(HttpServletRequest request,HttpServletResponse response, @RequestBody String requestBody ,@RequestParam String accessToken) { String address = String.join("", configProperty.getUnlimitMiniAppCode(), accessToken); try { logger.info("获取小程序二维码接口-请求报文:{}",requestBody); byte[] resultArray = WxQrCoodTool.sendRequestData(address, requestBody, "utf-8","utf-8",5000, 5000); WxQrCoodTool.returnImage(resultArray,response);//返回二进制图片流 } catch (Exception e) { } }
package com.rosellete.iescp.cshop.tool.http; import javax.servlet.http.HttpServletResponse; import java.io.*; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import java.util.Date; /** * http post发送工具,用于接收二进行文件流 * 该工具类一次性使用,不建议复用,专门针对微信post请求返回图片二进制流的功能进行了定制化处理,如果异常微信还可能会返回json串 * @author King */ public class WxQrCoodTool { private static final String DEFAULT_CHARSET = "utf-8"; public static void main(String[] args) throws Exception { String requestUrl = "http://i.ce.cn/ce/img4/jrwx.jpg"; byte[] resultsArray = WxQrCoodTool.sendRequestData(requestUrl,"requestData", "GBK", "GBK", 3000, 3000);//大家最终只要使用这一句代码就可调用 WxQrCoodTool.writeImageToFile(resultsArray,"C:\Users\King\Desktop\iescp-cshopadmin-activity-boot\aaaaaa123456789.png"); } /** * 发送报文 * * @param appName 应用系统英文名 * @param requestData 请求报文 * @param urlStr 请求地址 * @param connectionTimeout 链接超时时间 1000代表 1秒 * @param readTimeout 读取超时时间 1000代表1秒 * @return * @throws IOException * @author King */ public static byte[] sendRequestData(String urlStr, String requestData, String sendEncoding, String recvEncoding, int connectionTimeout, int readTimeout) throws IOException { InputStream inputStream = null; ByteArrayOutputStream byteArrayOutputStream = null; byte[] buff = new byte[1024]; int len = 0; URL url = null; HttpURLConnection conn = null; ByteArrayOutputStream byteOut = null; BufferedReader readInfo = null; StringBuffer strBuilder = new StringBuffer(); OutputStream outputStream = null; try { System.out.println("请求时间:【" + new Date() + "】"); System.out.println("请求地址:【" + urlStr + "】"); System.out.println("请求报文:【" + requestData + "】"); url = new URL(urlStr); conn = (HttpURLConnection) url.openConnection(); conn.setRequestMethod("POST"); //conn.setRequestProperty("SOAPAction", """"); //conn.setRequestProperty("Accept", "application/soap+xml, application/dime, multipart/related, text/*"); //如果没有下面这一行代码,服务器端可以通过request.getParameter()和request.getInputStream()都接收到相同信息 //conn.setRequestProperty("content-type", "text/xml;charset=GBK"); //如果 有上面这一行代码,服务器端仅能通过request.getInputStream()接收信息 //conn.setRequestProperty("User-Agent", "Axis/1.4"); conn.setRequestProperty("Cache-Control", "no-cache"); conn.setUseCaches(false); //忽略缓存 conn.setDoOutput(true); //使用 URL 连接进行输出 conn.setDoInput(true); //使用 URL 连接进行输入 conn.setConnectTimeout(connectionTimeout);//链接超时 conn.setReadTimeout(readTimeout);//读取超时 conn.connect();//建立链接 byteOut = new ByteArrayOutputStream(); byteOut.write(requestData.getBytes(sendEncoding));//以指定编码发送,如果有乱码,修改之 byte[] buf = byteOut.toByteArray(); outputStream = conn.getOutputStream(); outputStream.write(buf); outputStream.flush(); inputStream = conn.getInputStream(); byteArrayOutputStream = new ByteArrayOutputStream(); while ((len = inputStream.read(buff)) != -1) { byteArrayOutputStream.write(buff, 0, len); } return byteArrayOutputStream.toByteArray(); //if (HttpURLConnection.HTTP_OK == conn.getResponseCode()) {//正确返回 // readInfo = new BufferedReader(new java.io.InputStreamReader(conn.getInputStream(),recvEncoding));//以指定编码读取返回信息,如果有乱码,修改之 // String line = null; // while ((line = readInfo.readLine()) != null) { // strBuilder.append(line); // } //} else {//没有正确返回 // readInfo = new BufferedReader(new java.io.InputStreamReader(conn.getInputStream(),recvEncoding));//以指定编码读取返回信息,如果有乱码,修改之 // System.out.println("出现异常,返回报文:【"+readInfo+"】"); // throw new IOException("url请求出现问题,返回编码：" + conn.getResponseCode()); //} //System.out.println("返回时间:【"+new Date()+"】"); //System.out.println("返回报文:【"+strBuilder.toString()+"】"); } catch (UnsupportedEncodingException e) { throw e; } catch (MalformedURLException e) { throw e; } catch (IOException e) { throw e; } finally { try { if (readInfo != null) { readInfo.close(); } if (byteOut != null) { byteOut.close(); } if (outputStream != null) { outputStream.close(); } if (inputStream != null) { inputStream.close(); } if (byteArrayOutputStream != null) { byteArrayOutputStream.close(); } if (conn != null) { conn.disconnect(); } } catch (Exception e) { System.out.println("关闭链接出错!" + e.getMessage()); } } //return strBuilder.toString(); } /** * @param filePath 文件绝对路径 * @param encoding 读取文件的编码 * @return * @throws Exception * @author King */ public static String readStringFromFile(String filePath, String encoding) { File file = new File(filePath); System.out.println("文件 " + filePath + "存在与否?: " + file.exists() + " "); String tempLine = null; String retStr = ""; InputStreamReader isr = null;//way1: // FileReader fr = null;//way2 StringBuilder sb = new StringBuilder(); try { if (file.exists()) { isr = new InputStreamReader(new FileInputStream(file), encoding);//way1: // fr = new FileReader(file);//way2 BufferedReader br = new BufferedReader(isr);//way1: // BufferedReader br = new BufferedReader(fr);;//way2: tempLine = br.readLine(); while (tempLine != null) { sb.append(tempLine); tempLine = br.readLine(); } retStr = sb.toString(); } } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { try { if (isr != null) isr.close(); } catch (Exception e) { e.printStackTrace(); } } System.out.println("读到的文件内容如下:"); System.out.println(retStr + " "); return retStr; } /** * 通过response返回图片 * * @param response * @param resultArray */ public static void returnImage(byte[] resultArray, HttpServletResponse response) { response.setContentType("image/png"); ByteArrayInputStream bais = new ByteArrayInputStream(resultArray); OutputStream outputStream = null; try { outputStream = response.getOutputStream(); //创建存放文件内容的数组 byte[] buff = new byte[1024]; //所读取的内容使用n来接收 int n; //当没有读取完时,继续读取,循环 while ((n = bais.read(buff)) != -1) { //将字节数组的数据全部写入到输出流中 outputStream.write(buff, 0, n); } //强制将缓存区的数据进行输出 outputStream.flush(); //关流 outputStream.close(); } catch (IOException e) { e.printStackTrace(); } finally { try { bais.close(); } catch (IOException e) { e.printStackTrace(); } } } /** * 通过response返回图片 */ public static void writeImageToFile(byte[] resultArray, String path) { ByteArrayInputStream bais = new ByteArrayInputStream(resultArray); OutputStream outputStream = null; try { outputStream = new FileOutputStream(path); //创建存放文件内容的数组 byte[] buff = new byte[1024]; //所读取的内容使用n来接收 int n; //当没有读取完时,继续读取,循环 while ((n = bais.read(buff)) != -1) { //将字节数组的数据全部写入到输出流中 outputStream.write(buff, 0, n); } //强制将缓存区的数据进行输出 outputStream.flush(); //关流 outputStream.close(); } catch (IOException e) { e.printStackTrace(); } finally { if (outputStream != null) { try { outputStream.close(); } catch (IOException e) { e.printStackTrace(); } } if (bais != null) { try { bais.close(); } catch (IOException e) { e.printStackTrace(); } } } } }