HttpClient入门

简介

HttpClient 是 Apache HttpComponents 项目中的一个开源的 Java HTTP 客户端库，用于发送 HTTP 请求和处理 HTTP 响应。它提供了一组强大而灵活的 API，使得在 Java 程序中执行 HTTP 请求变得相对简单

maven依赖

org.apache.httpcomponents httpclient 4.5.2

或者导入阿里云oss

com.aliyun.oss aliyun-sdk-oss

里面包含了httpclient

核心API:-

• HttpClient.
• HttpClients
• CloseableHttpClient.
• HttpGet
• HttpPost

发送请求步骤

创建HttpClient对象

创建http请求对象

调用HttpClient的execute方法发送请求

示例get

  @Test
    public void httpGetTest() throws IOException {
        //获取创建HttpClient对象
        HttpClient httpClient = HttpClients.createDefault();
        //创建http请求对象
        HttpGet httpGet = new HttpGet("http://localhost:8080/user/shop/status");
        //调用HttpClient的execute方法发送请求，并获得响应
        HttpResponse response = httpClient.execute(httpGet);
        //获得响应的状态码
        int statusCode = response.getStatusLine().getStatusCode();
        System.out.println(statusCode);
        //获得响应体
        HttpEntity entity = response.getEntity();
        System.out.println(entity);
    }

示例post

@Test
    public void httpPostTest() throws IOException, JSONException {
        //获取创建HttpClient对象
        CloseableHttpClient httpClient = HttpClients.createDefault();
        //创建http请求对象
        HttpPost httpPost = new HttpPost("http://localhost:8080/admin/employee/login");
        JSONObject jsonObject = new JSONObject();
        //封装数据形式
        jsonObject.put("username","admin");
        jsonObject.put("password","123456");
        StringEntity stringEntity = new StringEntity(jsonObject.toString());
        stringEntity.setContentEncoding("utf8");
        stringEntity.setContentType("application/json");
        httpPost.setEntity(stringEntity);
        //调用HttpClient的execute方法发送请求，并获得响应
        CloseableHttpResponse response = httpClient.execute(httpPost);

        int statusCode = response.getStatusLine().getStatusCode();
        System.out.println(statusCode);
        HttpEntity entity = response.getEntity();
        System.out.println(entity);

    }