Java实现发送Get、Post请求仅需两步

前言

普通Java程序想要发送Get、Post等请求可以采用HttpClient实现，下面给出HttpClient使用方法，并已经封装成方法，直接拿去用即可

准备工作

在maven中导入依赖：

		<dependency>
            <groupId>org.apache.httpcomponentsgroupId>
            <artifactId>httpmimeartifactId>
            <version>4.5.13version> 
        dependency>
1
2
3
4
5

Get请求

记得在类中写上一个静态变量：private static HttpClient client = HttpClients.createDefault();

	/**
     * 发送HttpGet请求
     * @param url 请求的url
     * @param params get请求携带的参数
     * @param headers 请求头需要额外携带的参数
     * @return Sting格式的响应结果
     */
    public static String Get(String url, HashMap<String, String> params, HashMap<String, String> headers) {

        HttpGet httpGet = new HttpGet();

        // 设置请求头
        httpGet.addHeader("Accept", "application/json");
        httpGet.addHeader("Accept-Language", "zh-CN,zh;q=0.9");
        httpGet.addHeader("Connection", "keep-alive");
        httpGet.addHeader("Content-Type", "application/json; charset=utf-8");
        httpGet.addHeader("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.36");

        if (headers != null && headers.size() > 0) {
            headers.forEach(httpGet::addHeader);
        }

        // 设置参数
        if (params != null && params.size() > 0) {
            StringBuilder newUrl = new StringBuilder(url + "?");
            params.forEach((k, v) -> newUrl.append(k).append("=").append(v).append("&"));
            httpGet.setURI(URI.create(newUrl.toString()));
        }

        String response;
        try {
            HttpResponse execute = client.execute(httpGet);
            // 获取响应实体
            HttpEntity responseEntity = execute.getEntity();
            response = responseEntity != null ? EntityUtils.toString(responseEntity, "UTF-8") : "响应结果为null";
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

        return response;
    }
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41

Post请求

记得在类中写上一个静态变量：private static HttpClient client = HttpClients.createDefault();

	/**
     * 发送HttpPost请求
     * @param url 请求的url
     * @param payloads post请求携带的请求体
     * @param headers 请求头需要额外携带的参数
     * @return Sting格式的响应结果
     */
    public static String Post(String url, HashMap<String, String> payloads, HashMap<String, String> headers) {

        HttpPost httpPost = new HttpPost(url);

        // 设置请求头
        httpPost.addHeader("Accept", "application/json");
        httpPost.addHeader("Accept-Language", "zh-CN,zh;q=0.9");
        httpPost.addHeader("Connection", "keep-alive");
        httpPost.addHeader("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.36");

        if (headers != null && headers.size() > 0) {
            headers.forEach(httpPost::addHeader);
        }

        // 构建请求体参数
        if (payloads != null && payloads.size() > 0) {
            MultipartEntityBuilder entityBuilder = MultipartEntityBuilder.create();
            payloads.forEach((k, v) -> {
                if (k.equals("Boundary")) {
                    entityBuilder.setBoundary(v);
                } else {
                    entityBuilder.addTextBody(k, v);
                }
            });

            httpPost.setEntity(entityBuilder.build());
        }

        String response;
        try {
            HttpResponse execute = client.execute(httpPost);
            // 获取响应实体
            HttpEntity responseEntity = execute.getEntity();
            response = responseEntity != null ? EntityUtils.toString(responseEntity, "UTF-8") : "响应结果为null";
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

        return response;
    }
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47