在Java中，可以使用HttpURLConnection或者HttpClient來進行https請求。以下是使用HttpURLConnection進行https請求的示例代碼：

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

public class HttpsRequestExample {

    public static void main(String[] args) {
        try {
            String url = "https://example.com/api";
            URL obj = new URL(url);
            HttpURLConnection con = (HttpURLConnection) obj.openConnection();
            con.setRequestMethod("GET");

            BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
            String inputLine;
            StringBuffer response = new StringBuffer();

            while ((inputLine = in.readLine()) != null) {
                response.append(inputLine);
            }
            in.close();

            System.out.println(response.toString());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

如果希望使用HttpClient進行https請求，可以使用Apache HttpClient庫。以下是使用Apache HttpClient進行https請求的示例代碼：

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public class HttpsRequestExample {

    public static void main(String[] args) {
        try {
            String url = "https://example.com/api";
            HttpClient httpClient = HttpClients.createDefault();
            HttpGet httpGet = new HttpGet(url);
            HttpResponse response = httpClient.execute(httpGet);
            HttpEntity entity = response.getEntity();

            if (entity != null) {
                String result = EntityUtils.toString(entity);
                System.out.println(result);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

這兩種方法都可以用來進行https請求，具體選擇哪種方法取決于個人的偏好和項目要求。