springboot发送https的POST请求

在Spring Boot中发送HTTPS POST请求，需要进行如下步骤：

1. 创建SSLContext对象

private SSLContext createSSLContext() throws Exception {
    KeyStore keyStore = KeyStore.getInstance("JKS");
    InputStream inputStream = getClass().getResourceAsStream("/keystore.jks");
    keyStore.load(inputStream, "password".toCharArray());

    KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
    keyManagerFactory.init(keyStore, "password".toCharArray());

    TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
    trustManagerFactory.init(keyStore);

    SSLContext sslContext = SSLContext.getInstance("TLS");
    sslContext.init(keyManagerFactory.getKeyManagers(), trustManagerFactory.getTrustManagers(), new SecureRandom());

    return sslContext;
}

2. 创建HttpClient对象

private CloseableHttpClient createHttpClient() throws Exception {
    SSLContext sslContext = createSSLContext();
    SSLConnectionSocketFactory sslSocketFactory = new SSLConnectionSocketFactory(sslContext, new String[]{"TLSv1.2"}, null, SSLConnectionSocketFactory.getDefaultHostnameVerifier());

    return HttpClients.custom()
            .setSSLSocketFactory(sslSocketFactory)
            .build();
}

3. 发送POST请求

private void sendPostRequest() throws Exception {
    String url = "https://example.com/api";

    HttpPost httpPost = new HttpPost(url);
    httpPost.addHeader("Content-Type", "application/json");

    String requestBody = "{\"key\":\"value\"}";
    httpPost.setEntity(new StringEntity(requestBody, "UTF-8"));

    CloseableHttpClient httpClient = createHttpClient();
    try (CloseableHttpResponse response = httpClient.execute(httpPost)) {
        HttpEntity responseEntity = response.getEntity();
        String responseBody = EntityUtils.toString(responseEntity, "UTF-8");
        System.out.println(responseBody);
    }
}

在以上代码中，我们首先创建了一个SSLContext对象，该对象使用JKS格式的证书库，加载了我们的证书文件，并使用KeyManagerFactory和TrustManagerFactory初始化了SSLContext对象。

接着，我们创建了一个HttpClient对象，该对象使用我们之前创建的SSLContext对象，同时指定了TLSv1.2协议，以及默认的主机名验证器。

最后，我们使用HttpClient对象发送了一个POST请求，该请求包含了请求头Content-Type为application/json，以及请求体为一个JSON字符串的实体。我们通过execute方法执行请求，并获取响应实体的内容。