Java Httpclient 文件上传与接收

最新推荐文章于 2024-06-27 17:30:45 发布

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这篇博客展示了如何使用Java的HttpURLConnection类进行文件上传和下载操作。通过设置请求方法、请求头和输出流，实现了POST方式的文件上传，并在接收到HTTP_OK响应时读取并保存文件。同时，提供了接收文件的代码段，从HttpServletRequest中获取文件并保存到本地。整个过程涉及到了输入输出流的处理和异常的捕获。

导入pom依赖

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.4</version>
</dependency>
<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpmime</artifactId>
    <version>4.4</version>
</dependency>

上传代码：

    /**
     *
     * @param filepath 文件全路径
     * @param fileName  文件名
     * @return
     * @throws IOException
     */
    @PostMapping(value = "/upfileload.do")
    public String upfileload(String filepath,String fileName) throws IOException {
        System.out.println("传入参数------》" + filepath + "----" + fileName);
        DataInputStream in = null;
        OutputStream out = null;
        HttpURLConnection conn = null;
        JSONObject resposeTxt = null;
        InputStream ins = null;
        ByteArrayOutputStream outStream = null;
        try {
//            URL url = new URL("http://192.168.3.11:8081/mes-boot-doc/test/fileupload?fileName=shafei.xls");
            URL url = new URL("http://localhost:8009/fileupload?fileName="+fileName);

            conn = (HttpURLConnection) url.openConnection();
            // 发送POST请求必须设置如下两行
            conn.setDoOutput(true);
            conn.setUseCaches(false);
            conn.setRequestMethod("POST");
            conn.setRequestProperty("Content-Type", "text/html");
            conn.setRequestProperty("Cache-Control", "no-cache");
            conn.setRequestProperty("Charsert", "UTF-8");
            conn.connect();
            conn.setConnectTimeout(10000);
            out = conn.getOutputStream();

            File file = new File(filepath);
            in = new DataInputStream(new FileInputStream(file));

            int bytes = 0;
            byte[] buffer = new byte[1024];
            while ((bytes = in.read(buffer)) != -1) {
                out.write(buffer, 0, bytes);
            }
            out.flush();

            // 返回流
            if (conn.getResponseCode() == HttpURLConnection.HTTP_OK) {
                ins = conn.getInputStream();
                outStream = new ByteArrayOutputStream();
                byte[] data = new byte[1024];
                int count = -1;
                while ((count = ins.read(data, 0, 1024)) != -1) {
                    outStream.write(data, 0, count);
                }
                data = null;
                resposeTxt = JSONObject.parseObject(new String(outStream
                        .toByteArray(), "UTF-8"));
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (in != null) {
                in.close();
            }
            if (out != null) {
                out.close();
            }
            if (ins != null) {
                ins.close();
            }
            if (outStream != null) {
                outStream.close();
            }
            if (conn != null) {
                conn.disconnect();
            }
        }
        return  "SUCESS";
    }

接收代码：

@PostMapping("/fileupload")
public String uploadFile(HttpServletRequest request,HttpServletResponse response) throws Exception{
    String fileName = request.getParameter("fileName");
    System.out.println("filename:"+fileName);
    String fileFullPath = "C:/HWKJ/FTP/" + fileName;

    InputStream input = null;
    FileOutputStream fos = null;
    try {
        input = request.getInputStream();
        File file = new File("C:/HWKJ/FTP/");
        if(!file.exists()){
            file.mkdirs();
        }
        fos = new FileOutputStream(fileFullPath);
        int size = 0;
        byte[] buffer = new byte[1024];
        while ((size = input.read(buffer,0,1024)) != -1) {
            fos.write(buffer, 0, size);
        }

        //响应信息 json字符串格式
        Map<String,Object> responseMap = new HashMap<String,Object>();
        responseMap.put("flag", true);

        //生成响应的json字符串
        String jsonResponse = JSONObject.toJSONString(responseMap);
        sendResponse(jsonResponse,response);
    } catch (IOException e) {
        //响应信息 json字符串格式
        Map<String,Object> responseMap = new HashMap<String,Object>();
        responseMap.put("flag", false);
        responseMap.put("errorMsg", e.getMessage());
        String jsonResponse = JSONObject.toJSONString(responseMap);
        sendResponse(jsonResponse,response);
    } finally{
        if(input != null){
            input.close();
        }
        if(fos != null){
            fos.close();
        }
    }

    return null;
}

/**
 * 返回响应
 *
 * @throws Exception
 */
private void sendResponse(String responseString,HttpServletResponse response) throws Exception {
    response.setContentType("application/json;charset=UTF-8");
    PrintWriter pw = null;
    try {
        pw = response.getWriter();
        pw.write(responseString);
        pw.flush();
    } finally {
        IOUtils.closeQuietly(pw);
    }
}

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