如何解决“ java.security.cert.CertificateException：不存在使用者替代名称”错误？

public class RESTfulClientSSL {

    static TrustManager[] trustAllCerts = new TrustManager[]{new X509TrustManager() {
        @Override
        public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
            // TODO Auto-generated method stub
        }

        @Override
        public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
            // TODO Auto-generated method stub
        }

        @Override
        public X509Certificate[] getAcceptedIssuers() {
            // TODO Auto-generated method stub
            return null;
        }
    }};

    public class NullHostNameVerifier implements HostnameVerifier {
        /*
         * (non-Javadoc)
         *
         * @see javax.net.ssl.HostnameVerifier#verify(java.lang.String,
         * javax.net.ssl.SSLSession)
         */
        @Override
        public boolean verify(String arg0, SSLSession arg1) {
            // TODO Auto-generated method stub
            return true;
        }
    }

    public static void main(String[] args) {

        HttpURLConnection connection = null;
        try {

            HttpsURLConnection.setDefaultHostnameVerifier(new RESTfulwalkthroughCer().new NullHostNameVerifier());
            SSLContext sc = SSLContext.getInstance("SSL");
            sc.init(null, trustAllCerts, new SecureRandom());
            HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());


            String uriString = "https://172.20.20.12:9443/rest/hr/exposed/service";
            URL url = new URL(uriString);
            connection = (HttpURLConnection) url.openConnection();
            connection.setRequestMethod("GET");
            //connection.setRequestMethod("POST");

            BASE64Encoder encoder = new BASE64Encoder();
            String username = "admin";
            String password = "admin";
            String encodedCredential = encoder.encode((username + ":" + password).getBytes());
            connection.setRequestProperty("Authorization", "Basic " + encodedCredential);

            connection.connect();
            BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            int responseCode = connection.getResponseCode();
            if (responseCode == HttpURLConnection.HTTP_OK) {
                StringBuffer stringBuffer = new StringBuffer();
                String line = "";
                while ((line = reader.readLine()) != null) {
                    stringBuffer.append(line);
                }
                String content = stringBuffer.toString();
                System.out.println(content);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (connection != null) {
                connection.disconnect();
            }
        }
    }
}

  RestTemplate restTemplate = new RestTemplate();   
  TrustStrategy acceptingTrustStrategy = new TrustStrategy() {
            @Override
            public boolean isTrusted(java.security.cert.X509Certificate[] x509Certificates, String s) {
                return true;
            }

        };

        SSLContext sslContext = null;
        try {
            sslContext = org.apache.http.ssl.SSLContexts.custom().loadTrustMaterial(null, acceptingTrustStrategy)
                    .build();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (KeyManagementException e) {
            e.printStackTrace();
        } catch (KeyStoreException e) {
            e.printStackTrace();
        }
        SSLConnectionSocketFactory csf = new SSLConnectionSocketFactory(sslContext, new NoopHostnameVerifier());
        CloseableHttpClient httpClient = HttpClients.custom().setSSLSocketFactory(csf).build();
        HttpComponentsClientHttpRequestFactory requestFactory = new HttpComponentsClientHttpRequestFactory();
        requestFactory.setHttpClient(httpClient);

        restTemplate.setRequestFactory(requestFactory);
}

Subject Alternative Name:
DNS: example.com

**keytool -genkey -keyalg RSA -keystore keystore.jks -keysize 2048 -alias <IP_ADDRESS> -ext san=ip:<IP_ADDRESS>**

**openssl s_client -showcerts -connect <IP_ADDRESS>:443 < /dev/null | openssl x509 -outform PEM > myCert.pem**

**keytool -import -trustcacerts -keystore /home/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.242.b08-1.el7.x86_64/jre/lib/security/cacerts -alias <IP_ADDRESS> -file ./mycert.pem**

class MyTrustManager implements X509TrustManager {
public java.security.cert.X509Certificate[] getAcceptedIssuers() {
    return null;
}

public void checkClientTrusted(X509Certificate[] certs, String authType) {
}

public void checkServerTrusted(X509Certificate[] certs, String authType) {
}

@Override
public void checkClientTrusted(java.security.cert.X509Certificate[] paramArrayOfX509Certificate, String paramString)
        throws CertificateException {
    // TODO Auto-generated method stub

}

@Override
public void checkServerTrusted(java.security.cert.X509Certificate[] paramArrayOfX509Certificate, String paramString)
        throws CertificateException {
    // TODO Auto-generated method stub

}

private static void disableSSL() {
    try {
        TrustManager[] trustAllCerts = new TrustManager[] { new MyTrustManager() };

        // Install the all-trusting trust manager
        SSLContext sc = SSLContext.getInstance("SSL");
        sc.init(null, trustAllCerts, new java.security.SecureRandom());
        HostnameVerifier allHostsValid = new HostnameVerifier() {
            public boolean verify(String hostname, SSLSession session) {
                return true;
            }
        };
        HttpsURLConnection.setDefaultHostnameVerifier(allHostsValid);
        HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
    } catch (Exception e) {
        e.printStackTrace();
    }
}