Textlocal 发送短信失败，出现 java.net.ConnectException

Question

我正在尝试使用 textlocal java post API 发送短信，但由于 java.net.ConnectException 失败：连接超时：连接，请提供任何帮助。

public static void main(String[] args) {
    // TODO Auto-generated method stub
    try {
        // Construct data
        String apiKey = "apikey=" + "ODM0MDA0ZjQzODRlN2QzMzc3OGYyNGRmZGFhNDMwYjc=";
        String message = "&message=" + "Greetings from Simplifying Tech! Have a nice day!";
        String numbers = "&numbers=" + "0023423423";

        // Send data
        HttpURLConnection conn = (HttpURLConnection) new URL("https://api.textlocal.com/send/?").openConnection();
        String data = apiKey + numbers + message;
        conn.setDoOutput(true);
        conn.setRequestMethod("POST");
        conn.setRequestProperty("Content-Length", Integer.toString(data.length()));
        conn.getOutputStream().write(data.getBytes("UTF-8"));
         
        BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
        StringBuffer stringBuffer = new StringBuffer();
        String line;
        while ((line = rd.readLine()) != null) {
            stringBuffer.append(line).append("\n");
        }
        System.out.println(stringBuffer.toString());
        rd.close();


    } catch (Exception e) {
       e.printStackTrace();
    }


}

我遇到的失败与网络可达性或防火墙有关。有什么建议可以解决这个问题吗？

java.net.ConnectException: Connection timed out: connect
at java.base/sun.nio.ch.Net.connect0(Native Method)
at java.base/sun.nio.ch.Net.connect(Net.java:574)
at java.base/sun.nio.ch.Net.connect(Net.java:563)
at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:588)
at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:333)
at java.base/java.net.Socket.connect(Socket.java:648)
at java.base/sun.security.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:290)
at java.base/sun.security.ssl.BaseSSLSocketImpl.connect(BaseSSLSocketImpl.java:173)
at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:182)
at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:474)
at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:569)
at java.base/sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:265)
at java.base/sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:372)
at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:189)
at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1194)
at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1082)
at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:175)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getOutputStream0(HttpURLConnection.java:1375)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getOutputStream(HttpURLConnection.java:1350)
at java.base/sun.net.www.protocol.https.HttpsURLConnectionImpl.getOutputStream(HttpsURLConnectionImpl.java:220)
at smsP.Main.main(Main.java:25)