src/org/mxchange/jshopcore/model/customer/CustomerUtils.java

   1 /*
   2  * Copyright (C) 2015 Roland Haeder
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17 package org.mxchange.jshopcore.model.customer;
  18
  19 import java.sql.SQLException;
  20 import javax.persistence.EntityManager;
  21 import javax.persistence.EntityNotFoundException;
  22 import org.apache.commons.codec.binary.Base64;
  23 import org.apache.commons.codec.digest.Sha2Crypt;
  24 import org.mxchange.jcore.BaseFrameworkSystem;
  25 import org.mxchange.jshopcore.model.order.Orderable;
  26 import org.mxchange.jshopcore.model.order.ShopOrder;
  27
  28 /**
  29  * An utilities class for customers
  30  * <p>
  31  * @author Roland Haeder
  32  */
  33 public class CustomerUtils extends BaseFrameworkSystem {
  34
  35         /**
  36          * Generates an unique access key.
  37          * <p>
  38          * @param em Entity manager instance
  39          * @param customer Customer instance
  40          * <p>
  41          * @return An unique access key
  42          */
  43         public static String generateAccessKey (final EntityManager em, final Customer customer) {
  44                 // Trace message
  45                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateAccessKey: connection={0} - CALLED!", connection));
  46
  47                 // em cannot be null
  48                 if (null == em) {
  49                         // Abort here
  50                         throw new NullPointerException("em is null"); //NOI18N
  51                 } else if (!em.isOpen()) {
  52                         // Not open
  53                         throw new IllegalStateException("Entity manager is closed.");
  54                 }
  55
  56                 // Generate fake order instance
  57                 Orderable orderable = null;
  58
  59                 // Generate access keyy
  60                 String accessKey = null;
  61
  62                 // Default is found
  63                 boolean isFound = true;
  64
  65                 // Is the number used?
  66                 while (isFound) {
  67                         // Both number parts
  68                         String randString = String.format("%s:%s:%s", Long.toHexString(Math.round(Math.random() * 1_000_000)), em, customer.getCustomerNumber());
  69
  70                         // Generate access key, use SHA512 hashing and BASE64-encoding for strong key generation
  71                         accessKey = Base64.encodeBase64String(Sha2Crypt.sha512Crypt(randString.getBytes()).getBytes()).substring(0, 100);
  72
  73                         // Try this
  74                         try {
  75                                 // Get reference
  76                                 orderable = em.getReference(ShopOrder.class, accessKey);
  77                         } catch (final EntityNotFoundException ex) {
  78                                 // Not found, so abort loop here
  79                                 isFound = false;
  80                         }
  81                 }
  82
  83                 // Trace message
  84                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateAccessKey: accessKey={0} - EXIT!", accessKey));
  85                 // Found one
  86                 return accessKey;
  87         }
  88
  89         /**
  90          * Generates an unique customer number by checking is existence
  91          * <p>
  92          * @param em Entity manager instance
  93          * <p>
  94          * @return Generated customer number (not used before)
  95          * <p>
  96          * @throws java.sql.SQLException If any SQL error occured
  97          */
  98         public static String generateCustomerNumber (final EntityManager em) throws SQLException {
  99                 // Trace message
 100                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateCustomerNumber: connection={0} - CALLED!", connection));
 101
 102                 // em cannot be null
 103                 if (null == em) {
 104                         // Abort here
 105                         throw new NullPointerException("em is null"); //NOI18N
 106                 } else if (!em.isOpen()) {
 107                         // Not open
 108                         throw new IllegalStateException("Entity manager is closed.");
 109                 }
 110
 111                 // Generate number
 112                 String customerNumber = null;
 113
 114                 // Default is found
 115                 boolean isFound = true;
 116
 117                 // Is the number used?
 118                 while (isFound) {
 119                         // Both number parts
 120                         long part1 = Math.round(Math.random() * 100_000);
 121                         long part2 = Math.round(Math.random() * 1_000);
 122
 123                         // Generate new number
 124                         customerNumber = String.format("%s-%s", part1, part2); //NOI18N
 125
 126                         // Try it
 127                         try {
 128                                 // Get instance
 129                                 Customer customer = em.getReference(ShopCustomer.class, customerNumber);
 130                         } catch (final EntityNotFoundException ex) {
 131                                 // Not found
 132                                 isFound = false;
 133                         }
 134                 }
 135
 136                 // Trace message
 137                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateCustomerNumber: customerNumber={0} - EXIT!", customerNumber));
 138                 // Found one
 139                 return customerNumber;
 140         }
 141
 142         /**
 143          * No instance from this class
 144          */
 145         private CustomerUtils () {
 146         }
 147 }