httpclient表单提交参数以及文件

蔚落 2024-04-17 19:18 67阅读 0赞

废话不多说，直接上代码

public class HttpClient {
    	private static String charset = "UTF-8";
    	// 此方法是POST请求上传的参数中包含本地图片信息File类型
    	public String request(String url, HashMap<String, Object> fields, HashMap<String, File> files,HashMap<String,String>headers) throws Exception {
        CloseableHttpClient httpClient = HttpClients.createDefault();
        CloseableHttpResponse response = null;
        String result = null;
    // HttpClient请求的相关设置，可以不用配置，用默认的参数，这里设置连接和超时时长(毫秒)
        RequestConfig config = RequestConfig.custom().setConnectTimeout(30000).setSocketTimeout(30000).build();
        try {
            MultipartEntityBuilder entityBuilder = MultipartEntityBuilder.create();
            addFiles(entityBuilder, files);
            addFields(entityBuilder, fields);
            HttpPost httpPost = new HttpPost(url);
            if(headers!=null&&headers.size()!=0) {
    		  //httpPost.setHeader("Content-Type", headers.get("Content-Type"));
              //httpPost.setHeader("Authorization", headers.get("Authorization"));
              addHeaders(httpPost , headers);
            }
            HttpEntity reqEntity = entityBuilder.build();
            httpPost.setEntity(reqEntity);
            httpPost.setConfig(config);
    	// 执行网络请求并返回结果
            response = httpClient.execute(httpPost);
            HttpEntity resEntity = response.getEntity();
            if (resEntity != null) {
                result = streamToString(resEntity.getContent(), charset);
            }
            EntityUtils.consume(resEntity);
        } finally {
            response.close();
            httpClient.close();
        }
    	// 得到的是JSON类型的数据需要第三方解析JSON的jar包来解析
        return result;
    }
    
    
    private void addFiles(MultipartEntityBuilder entityBuilder, HashMap<String, File> files) {
        if (files == null) {
            return;
        }
        for (String name : files.keySet()) {
            File file = files.get(name);
            FileBody fileBody = new FileBody(file);
            entityBuilder.addPart(name, fileBody);
        }
    }
    
    
    private void addFields(MultipartEntityBuilder entityBuilder, HashMap<String, Object> fields) {
        for (String name : fields.keySet()) {
            String value = fields.get(name).toString();
            StringBody StringBody = new StringBody(value, ContentType.TEXT_PLAIN);
            entityBuilder.addPart(name, StringBody);
        }
    }
    
    private void addHeaders(HttpPost httpPost , HashMap<String, Object> fields) {
        for (String name : fields.keySet()) {
            String value = fields.get(name).toString();
        	httpPost.setHeader(name, value);
        }
    }
    
    
    // 此方法是把传进的字节流转化为相应的字符串并返回，此方法一般在网络请求中用到
    private String streamToString(InputStream inputStream, String charset) throws Exception {
        StringBuilder stringBuilder = new StringBuilder();
        try (InputStreamReader inputStreamReader = new InputStreamReader(inputStream, charset)) {
            try (BufferedReader reader = new BufferedReader(inputStreamReader)) {
                String line = null;
                while ((line = reader.readLine()) != null) {
                    stringBuilder.append(line).append("\r\n");
                }
            }
        }
        return stringBuilder.toString();
    }
    
    public static void main(String[] args) throws Exception {
        File file=new File("xxxxxxxxxx");
        HttpClient httpClient = new HttpClient();
        HashMap<String,File> files = new HashMap<>();
        HashMap<String,Object> datas = new HashMap<>();
        HashMap<String,String> headers = new HashMap<>();
        String url="xxxxxxx";
      // headers.put("Content-Type", "multipart/form-data");
        headers.put("Authorization", "xxxxxx");
        datas.put("xxxxx","xxxxx");
        files.put("file",file);   
        String result = httpClient.request(url,datas,files,headers);
        System.out.println(result);
    }
    }

**注意 main方法中的headers是不需要加的，不然会报错**

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.web.multipart.MultipartException: Could not parse multipart servlet request; nested exception is org.apache.commons.fileupload.FileUploadException: the request was rejected because no multipart boundary was found

头部会自动加好，不要画足添蛇  
[参考链接][Link 1] [https://blog.csdn.net/sanjay\_f/article/details/47407063][Link 1]

如果你是MultipartFile类型 也可以转成File，方法集成进去就行了，参考 [https://blog.csdn.net/qq\_39699665/article/details/83081431][https_blog.csdn.net_qq_39699665_article_details_83081431]

/**
         * MultipartFile 转 File
         * @param file
         * @throws Exception
         */
        public static File multipartFileToFile( @RequestParam MultipartFile file) throws Exception {
    
            File toFile = null;
            if(file.equals("")||file.getSize()<=0){
                file = null;
    
            }else {
                InputStream ins = null;
                ins = file.getInputStream();
                toFile = new File(file.getOriginalFilename());
                inputStreamToFile(ins, toFile);
                ins.close();
            }
            return toFile;
        }

[Link 1]: https://blog.csdn.net/sanjay_f/article/details/47407063
[https_blog.csdn.net_qq_39699665_article_details_83081431]: https://blog.csdn.net/qq_39699665/article/details/83081431