HTTP协议客户端之HttpClient的基本使用-蒲公英云

HTTP协议客户端之HttpClient的基本使用

心已赠人 2023-09-27 15:59 200阅读 0赞

HttpClient的基本使用

概述

HttpClient 是Apache Jakarta Common 下的子项目，可以用来提供高效的、最新的、功能丰富的支持 HTTP 协议的客户端编程工具包，并且它支持 HTTP 协议最新的版本和建议。

HttpClient相比JDK自带的URLConnection，增加了易用性和灵活性，使客户端发送Http请求变得更加容易，而且也方便开发测试接口，大大提高开发的效率。

常用HTTP协议客户端包括有：httpclient、restTemplate、okHttp

官网：https://hc.apache.org/index.html

添加依赖

<dependency>
     <groupId>org.apache.httpcomponents</groupId>
     <artifactId>httpclient</artifactId>
     <version>4.5.13</version>
 </dependency>

Get请求

1.无参数的GET请求

@Test
    public void get() throws IOException {
        // 创建HttpClient对象
        CloseableHttpClient httpClient = HttpClients.createDefault();
        // 创建HttpGet请求
        HttpGet httpGet = new HttpGet("https://www.baidu.com");
        // 响应对象
        CloseableHttpResponse response = null;
        try {
            // 使用HttpClient发起请求
            response = httpClient.execute(httpGet);
            // 判断响应状态码是否为200
            if (response.getStatusLine().getStatusCode() == 200) {
                // 获取返回数据
                HttpEntity httpEntity = response.getEntity();
                String content = EntityUtils.toString(httpEntity, "UTF-8");
                // 打印数据长度
                log.info("content:{}", content);
            }
        } finally {
            // 释放连接
            if (response != null) {
                response.close();
            }
            httpClient.close();
        }
    }

2.带参数的GET请求

HttpGet httpGet = new HttpGet("https://www.baidu.com/s?wd=java");

POST请求

1.无参数的POST请求

@Test
    public void post() throws IOException {
        // 创建HttpClient对象
        CloseableHttpClient httpClient = HttpClients.createDefault();
        // 创建HttpGet请求
        HttpPost httpPost = new HttpPost("http://www.baidu.com");
        // 响应对象
        CloseableHttpResponse response = null;
        try {
            // 使用HttpClient发起请求
            response = httpClient.execute(httpPost);
            // 判断响应状态码是否为200
            if (response.getStatusLine().getStatusCode() == 200) {
                // 获取返回数据
                HttpEntity httpEntity = response.getEntity();
                String content = EntityUtils.toString(httpEntity, "UTF-8");
                // 打印数据长度
                log.info("content:{}", content);
            }
        } finally {
            // 释放连接
            if (response != null) {
                response.close();
            }
            httpClient.close();
        }
    }

2.带参数的POST请求

public static void main(String[] args) throws Exception {
        // 创建HttpClient对象
        CloseableHttpClient httpClient = HttpClients.createDefault();
        // 创建HttpPost对象，设置url访问地址
        HttpPost httpPost = new HttpPost("https://fanyi.baidu.com/langdetect");
        // 声明List集合，封装表单中的参数
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        // 实际请求地址：https://fanyi.baidu.com/langdetect?query=Jav