Java HttpsURLConnection忽略crt访问https链接

public static void main(String argv[]){
String urlStr = "https://github.com/Unknwon/go-fundamental-programming";
try {
URL url = new URL(urlStr);
HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();

TrustManager[] trustManagers = new TrustManager[]{
new X509TrustManager() {
public void checkClientTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
}

public void checkServerTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
}

public X509Certificate[] getAcceptedIssuers() {
return null;
}
}
};
SSLContext ctx = SSLContext.getInstance("TLS");
ctx.init(null,trustManagers,null);

connection.setSSLSocketFactory(ctx.getSocketFactory());
connection.setRequestMethod("GET");

System.out.println(connection.getResponseCode());

BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream(),"utf-8"));
String line = null;
StringBuffer sb = new StringBuffer();
while ((line = br.readLine())!=null){
sb.append(line);
sb.append("\n");
}
String response = sb.toString();
System.out.print(response);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (KeyManagementException e) {
e.printStackTrace();
}
}