Java实现Postman中form-data参数发送post请求

其中一个方法使用到了 MultipartEntityBuilder
依赖如下

<dependency>
	<groupId>org.apache.httpcomponents</groupId>
	<artifactId>httpmime</artifactId>
	<version>4.5</version>
</dependency>

httpclient的相关依赖

<!-- httpclient 相关依赖-->
       <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpcore</artifactId>
            <version>4.4.10</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient -->
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.5.6</version>
        </dependency>
 
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpmime</artifactId>
            <version>4.5</version>
        </dependency>

Java方法编码如下
三种方式都可行

    /**
     * 以post方式调用第三方接口,以form-data 形式  发送数据
     *
     * @param url  post请求url
     * @param param 表单里其他参数
     * @return
     */
    public static JSONObject doPostForm(String url, Map<String, String> param) {
        // 创建Httpclient对象
        CloseableHttpClient httpClient = HttpClients.createDefault();
        CloseableHttpResponse response = null;
        String resultString = "";
        JSONObject result = null;
        try {
            // 创建Http Post请求
            HttpPost httpPost = new HttpPost(url);
            // 创建参数列表
            if (param != null) {
                List<NameValuePair> paramList = new ArrayList<>();
                for (String key : param.keySet()) {
                    paramList.add(new BasicNameValuePair(key, param.get(key)));
                }
                // 模拟表单
                UrlEncodedFormEntity entity = new UrlEncodedFormEntity(paramList);
                httpPost.setEntity(entity);
            }
            // 执行http请求
            response = httpClient.execute(httpPost);
            resultString = EntityUtils.toString(response.getEntity(), "utf-8");
            result = JSONObject.parseObject(resultString);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                response.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return result;
    }

    /**
     * 以post方式调用第三方接口,以form-data 形式  发送数据
     *
     * @param url  post请求url
     * @param map 表单里其他参数
     * @return
     */
    public static JSONObject doPostFormTwo(String url, Map<String, String> map) throws Exception {
        String result = "";
        CloseableHttpClient client = null;
        CloseableHttpResponse response = null;
        RequestConfig defaultRequestConfig = RequestConfig.custom().setSocketTimeout(550000).setConnectTimeout(550000)
                .setConnectionRequestTimeout(550000).setStaleConnectionCheckEnabled(true).build();
        client = HttpClients.custom().setDefaultRequestConfig(defaultRequestConfig).build();
        // client = HttpClients.createDefault();
        URIBuilder uriBuilder = new URIBuilder(url);

        HttpPost httpPost = new HttpPost(uriBuilder.build());
        httpPost.setHeader("Connection", "Keep-Alive");
        httpPost.setHeader("Charset", "UTF-8");
        httpPost.setHeader("Content-Type", "application/x-www-form-urlencoded");
        Iterator<Map.Entry<String, String>> it = map.entrySet().iterator();
        List<NameValuePair> params = new ArrayList<NameValuePair>();

        while (it.hasNext()) {
            Map.Entry<String, String> entry = it.next();
            NameValuePair pair = new BasicNameValuePair(entry.getKey(), entry.getValue());
            params.add(pair);
        }

        httpPost.setEntity(new UrlEncodedFormEntity(params, "UTF-8"));
        try {
            response = client.execute(httpPost);
            if (response != null) {
                HttpEntity resEntity = response.getEntity();
                if (resEntity != null) {
                    result = EntityUtils.toString(resEntity, "UTF-8");
                }
            }
        } catch (ClientProtocolException e) {
            throw new RuntimeException("创建连接失败" + e);
        } catch (IOException e) {
            throw new RuntimeException("创建连接失败" + e);
        }

        return JSONObject.parseObject(result);
    }

    /**
     * 以post方式调用第三方接口,以form-data 形式  发送数据
     *
     * @param url  post请求url
     * @param paramMap 表单里其他参数
     * @return
     */
    public static JSONObject doPostFormThree(String url, Map<String, String> paramMap) {
        // 创建Http实例
        CloseableHttpClient httpClient = HttpClients.createDefault();
        // 创建HttpPost实例
        HttpPost httpPost = new HttpPost(url);
        try {
            MultipartEntityBuilder builder = MultipartEntityBuilder.create();
            builder.setCharset(java.nio.charset.Charset.forName("UTF-8"));
            builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);

            //表单中参数
            for(Map.Entry<String, String> entry: paramMap.entrySet()) {
                builder.addPart(entry.getKey(),new StringBody(entry.getValue(), ContentType.create("text/plain", Consts.UTF_8)));
            }

            HttpEntity entity = builder.build();
            httpPost.setEntity(entity);
            HttpResponse response = httpClient.execute(httpPost);// 执行提交

            if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                // 返回
                String res = EntityUtils.toString(response.getEntity(), java.nio.charset.Charset.forName("UTF-8"));
                return JSONObject.parseObject(res);
            }
        } catch (Exception e) {
            e.printStackTrace();
            log.error("调用HttpPost失败！" + e.toString());
        } finally {
            if (httpClient != null) {
                try {
                    httpClient.close();
                } catch (IOException e) {
                    log.error("关闭HttpPost连接失败！");
                }
            }
        }
        return null;
    }