    /******************************************************************************************
     * This example code is provided for illustrative purposes only and provided 'AS IS'
     * without warranty of any kind.
     *
     * Copyright ©2014 Chrysler Group LLC.  All Rights Reserved.  All information contained
     * herein is,and remains the property of Chrysler Group LLC and its suppliers, if any.
     * The intellectual and technical concepts contained herein are proprietary to Chrysler
     * Group LLC and its suppliers and may be covered by U.S. and Foreign Patents, patents in
     * process, and are protected by trade secret or copyright law. Dissemination of this
     * information or reproduction of this material is strictly forbidden unless prior written
     * permission is obtained from Chrysler Group LLC.
     *
     * Chrysler, Jeep, Dodge, Ram, SRT, Mopar and the Pentastar logo are registered trademarks of
     * Chrysler Group LLC. FIAT is a registered trademark of Fiat group Marketing & Corporate
     * Communication S.p.A. used under license by Chrysler Group LLC.
     *******************************************************************************************/
    package com.fca.uconnect.global.client;

    import java.io.BufferedInputStream;
    import java.io.DataInputStream;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.IOException;
    import java.math.BigInteger;
    import java.security.KeyStore;
    import java.security.KeyStoreException;
    import java.security.NoSuchAlgorithmException;
    import java.security.PrivateKey;
    import java.security.SecureRandom;
    import java.security.cert.Certificate;
    import java.security.cert.CertificateException;
    import java.security.cert.CertificateFactory;
    import com.amazonaws.services.iot.client.AWSIotException;
    import com.amazonaws.services.iot.client.AWSIotMqttClient;

    public class ExampleForMQTTUsingKeyStore {

    	private AWSIotMqttClient mqttClient;
    	public void process() {

    		KeyStorePasswordPair pair = getKeyStorePasswordPair("certificateFile", "privateKeyFile","KeyAlgorithm");
     		mqttClient = new AWSIotMqttClient("clientEndpoint", "TBMClientId", pair.keyStore, pair.keyPassword);
    		mqttClient.setConnectionTimeout(5000); // In this example Time out for establishing Connection is set to 5 Seconds.
    		mqttClient.setKeepAliveInterval(1440000); // In this example Keep Alive is  set to 24 minutes.

    		try {
    			mqttClient.connect();

    		} catch (AWSIotException e) {
    			e.printStackTrace();
    		}
    	}
    	public static KeyStorePasswordPair getKeyStorePasswordPair(String certificateFile, String privateKeyFile,
                String keyAlgorithm) {
            if (certificateFile == null || privateKeyFile == null) {
                System.out.println("Certificate or private key file missing");
                return null;
            }
            Certificate certificate = null;
            File file = new File(certificateFile);
            if (!file.exists()) {
                System.out.println("Certificate file not found: " + certificateFile);
                return null;
            }
            try (BufferedInputStream stream = new BufferedInputStream(new FileInputStream(file))) {
                CertificateFactory certFactory = CertificateFactory.getInstance("X.509");
                certificate = certFactory.generateCertificate(stream);
            } catch (IOException | CertificateException e) {
                System.out.println("Failed to load certificate file " + certificateFile);
            }
          //get the Private key for private File , It can be implemented with Java.security Package
            PrivateKey privateKey = null;
            //get KeyStorePasswordPair , It can be implemented with Java.security Package.
            return keystorePasswordPair;

        }
    	 	    public static class KeyStorePasswordPair {
    	        public KeyStore keyStore;
    	        public String keyPassword;
    	        public KeyStorePasswordPair(KeyStore keyStore, String keyPassword) {
    	            this.keyStore = keyStore;
    	            this.keyPassword = keyPassword;
    	        }
    	    }
    }

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