java如何发送http请求

147 阅读1分钟

环境

  • springboot

依赖

 <dependency>
      <groupId>org.apache.httpcomponents</groupId>
      <artifactId>httpclient</artifactId>
 </dependency>

 <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>fastjson</artifactId>
      <version>1.2.72</version>
</dependency>

测试

1.get请求

 /**
     * 普通get请求
     */
    @Test
    public void doGetTest(){
        // 获得Http客户端(可以理解为:你得先有一个浏览器;注意:实际上HttpClient与浏览器是不一样的)
        CloseableHttpClient httpClient = HttpClientBuilder.create().build();
        // 创建Get请求
        HttpGet httpGet = new HttpGet("http://apis.juhe.cn/mobile/get");

        // 响应模型
        CloseableHttpResponse response = null;

        try {
            // 由客户端执行(发送)Get请求
            response = httpClient.execute(httpGet);
            // 从响应模型中获取响应实体
            HttpEntity responseEntity = response.getEntity();
            System.out.println("响应状态为:" + response.getStatusLine());
            if (responseEntity != null) {
                System.out.println("响应内容长度为:" + responseEntity.getContentLength());
                System.out.println("响应内容为:" + EntityUtils.toString(responseEntity));
            }
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (ParseException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                // 释放资源
                if (httpClient != null) {
                    httpClient.close();
                }
                if (response != null) {
                    response.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

    }

2.post请求

 /**
     * 普通post请求
     */
    @Test
    public void doPostTest(){
        // 获得Http客户端(可以理解为:你得先有一个浏览器;注意:实际上HttpClient与浏览器是不一样的)
        CloseableHttpClient httpClient = HttpClientBuilder.create().build();

        // 参数
        StringBuffer params = new StringBuffer();
        try {
            // 字符数据最好encoding以下;这样一来,某些特殊字符才能传过去(如:某人的名字就是“&”,不encoding的话,传不过去)
            //第一个参数是名字,第二个参数是编码格式
            params.append("key=" + URLEncoder.encode("12345", "utf-8"));
            params.append("&");
            params.append("phone=345322");
        } catch (UnsupportedEncodingException e1) {
            e1.printStackTrace();
        }

        // 创建Post请求
        HttpPost httpPost = new HttpPost("http://apis.juhe.cn/mobile/get" + "?" + params);

        // 设置ContentType(注:如果只是传普通参数的话,ContentType不一定非要用application/json)
        httpPost.setHeader("Content-Type", "application/json;charset=utf8");

        // 响应模型
        CloseableHttpResponse response = null;
        try {
            // 由客户端执行(发送)Post请求
            response = httpClient.execute(httpPost);
            // 从响应模型中获取响应实体
            HttpEntity responseEntity = response.getEntity();

            System.out.println("响应状态为:" + response.getStatusLine());
            if (responseEntity != null) {
                System.out.println("响应内容长度为:" + responseEntity.getContentLength());
                System.out.println("响应内容为:" + EntityUtils.toString(responseEntity));
            }
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (ParseException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                // 释放资源
                if (httpClient != null) {
                    httpClient.close();
                }
                if (response != null) {
                    response.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

    }