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          * No instance from this class
  37          */
  38         private CustomerUtils () {
  39         }
  40
  41         /**
  42          * Generates an unique customer number by checking is existence
  43          * <p>
  44          * @param em Entity manager instance
  45          * <p>
  46          * @return Generated customer number (not used before)
  47          * <p>
  48          * @throws java.sql.SQLException If any SQL error occured
  49          */
  50         public static String generateCustomerNumber (final EntityManager em) throws SQLException {
  51                 // Trace message
  52                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateCustomerNumber: connection={0} - CALLED!", connection));
  53
  54                 // em cannot be null
  55                 if (null == em) {
  56                         // Abort here
  57                         throw new NullPointerException("em is null"); //NOI18N
  58                 } else if (!em.isOpen()) {
  59                         // Not open
  60                         throw new IllegalStateException("Entity manager is closed.");
  61                 }
  62
  63                 // Generate number
  64                 String customerNumber = null;
  65
  66                 // Default is found
  67                 boolean isFound = true;
  68
  69                 // Is the number used?
  70                 while (isFound) {
  71                         // Both number parts
  72                         long part1 = Math.round(Math.random() * 100_000);
  73                         long part2 = Math.round(Math.random() * 1_000);
  74
  75                         // Generate new number
  76                         customerNumber = String.format("%s-%s", part1, part2); //NOI18N
  77
  78                         // Try it
  79                         try {
  80                                 // Get instance
  81                                 Customer customer = em.getReference(ShopCustomer.class, customerNumber);
  82                         } catch (final EntityNotFoundException ex) {
  83                                 // Not found
  84                                 isFound = false;
  85                         }
  86                 }
  87
  88                 // Trace message
  89                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateCustomerNumber: customerNumber={0} - EXIT!", customerNumber));
  90                 // Found one
  91                 return customerNumber;
  92         }
  93
  94         /**
  95          * Generates an unique access key.
  96          * <p>
  97          * @param em Entity manager instance
  98          * @param customer Customer instance
  99          * <p>
 100          * @return An unique access key
 101          */
 102         public static String generateAccessKey (final EntityManager em, final Customer customer) {
 103                 // Trace message
 104                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateAccessKey: connection={0} - CALLED!", connection));
 105
 106                 // em cannot be null
 107                 if (null == em) {
 108                         // Abort here
 109                         throw new NullPointerException("em is null"); //NOI18N
 110                 } else if (!em.isOpen()) {
 111                         // Not open
 112                         throw new IllegalStateException("Entity manager is closed.");
 113                 }
 114
 115                 // Generate fake order instance
 116                 Orderable orderable = null;
 117
 118                 // Generate access keyy
 119                 String accessKey = null;
 120
 121                 // Default is found
 122                 boolean isFound = true;
 123
 124                 // Is the number used?
 125                 while (isFound) {
 126                         // Both number parts
 127                         String randString = String.format("%s:%s:%s", Long.toHexString(Math.round(Math.random() * 1_000_000)), em, customer.getCustomerNumber());
 128
 129                         // Generate access key, use SHA512 hashing and BASE64-encoding for strong key generation
 130                         accessKey = Base64.encodeBase64String(Sha2Crypt.sha512Crypt(randString.getBytes()).getBytes()).substring(0, 100);
 131
 132                         // Try this
 133                         try {
 134                                 // Get reference
 135                                 orderable = em.getReference(ShopOrder.class, accessKey);
 136                         } catch (final EntityNotFoundException ex) {
 137                                 // Not found, so abort loop here
 138                                 isFound = false;
 139                         }
 140                 }
 141
 142                 // Trace message
 143                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateAccessKey: accessKey={0} - EXIT!", accessKey));
 144                 // Found one
 145                 return accessKey;
 146         }
 147 }