用JDK17 写个POST请求

在Java 17中，我们可以使用内置的HttpURLConnection或者第三方库如Spring框架或Apache HttpClient来发送POST请求。这里我将提供一个基本的示例，展示如何使用HttpURLConnection：

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

public class PostRequestExample {
    public static void main(String[] args) throws Exception {
        // URL endpoint for your POST request
        String url = "https://api.example.com/endpoint";

        try (BufferedReader in = new BufferedReader(new InputStreamReader(System.in))) {
            // Read user input for the request body (JSON, form data, etc.)
            String requestBody = "{'key': 'value'}"; // Replace with actual content

            // Create a HttpURLConnection object
            HttpURLConnection conn = (HttpURLConnection) new URL(url).openConnection();
            conn.setRequestMethod("POST");
            conn.setRequestProperty("Content-Type", "application/json"); // Set appropriate content type for JSON
            conn.setDoOutput(true); // Enable output to send the request body

            // Write the request body
            byte[] requestBodyBytes = requestBody.getBytes("UTF-8");
            conn.getOutputStream().write(requestBodyBytes);

            // Get the response code
            int responseCode = conn.getResponseCode();

            if (responseCode == HttpURLConnection.HTTP_OK) {
                System.out.println("POST request successful, response code: " + responseCode);
                // Read and print the response if needed
                readResponse(conn.getInputStream());
            } else {
                System.err.println("Error: " + responseCode);
            }
        }
    }

    private static void readResponse(InputStream inputStream) throws Exception {
        StringBuilder response = new StringBuilder();
        String line;
        while ((line = inputStream.readLine()) != null) {
            response.append(line);
        }
        System.out.println("Response: " + response.toString());
    }
}