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          * @return Generated customer number (not used before)
  46          * @throws java.sql.SQLException If any SQL error occured
  47          */
  48         public static String generateCustomerNumber (final EntityManager em) throws SQLException {
  49                 // Trace message
  50                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateCustomerNumber: connection={0} - CALLED!", connection));
  51
  52                 // em cannot be null
  53                 if (null == em) {
  54                         // Abort here
  55                         throw new NullPointerException("em is null"); //NOI18N
  56                 } else if (!em.isOpen()) {
  57                         // Not open
  58                         throw new IllegalStateException("Entity manager is closed.");
  59                 }
  60
  61                 // Fake customer instance
  62                 Customer customer = null;
  63
  64                 // Generate number
  65                 String customerNumber = null;
  66
  67                 // Default is found
  68                 boolean isFound = true;
  69
  70                 // Declare variables
  71                 long part1;
  72                 long part2;
  73
  74                 // Is the number used?
  75                 while (isFound) {
  76                         // Both number parts
  77                         part1 = Math.round(Math.random() * 100_000);
  78                         part2 = Math.round(Math.random() * 1_000);
  79
  80                         // Generate new number
  81                         customerNumber = String.format("%s-%s", part1, part2); //NOI18N
  82
  83                         // Try it
  84                         try {
  85                                 // Get instance
  86                                 customer = em.getReference(ShopCustomer.class, customerNumber);
  87                         } catch (final EntityNotFoundException ex) {
  88                                 // Not found
  89                                 isFound = false;
  90                         }
  91                 }
  92
  93                 // Trace message
  94                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateCustomerNumber: customerNumber={0} - EXIT!", customerNumber));
  95                 // Found one
  96                 return customerNumber;
  97         }
  98
  99         /**
 100          * Generates an unique access key.
 101          * <p>
 102          * @param em Entity manager instance
 103          * @param customer Customer instance
 104          * @return An unique access key
 105          */
 106         public static String generateAccessKey (final EntityManager em, final Customer customer) {
 107                 // Trace message
 108                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateAccessKey: connection={0} - CALLED!", connection));
 109
 110                 // em cannot be null
 111                 if (null == em) {
 112                         // Abort here
 113                         throw new NullPointerException("em is null"); //NOI18N
 114                 } else if (!em.isOpen()) {
 115                         // Not open
 116                         throw new IllegalStateException("Entity manager is closed.");
 117                 }
 118
 119                 // Generate fake order instance
 120                 Orderable orderable = null;
 121
 122                 // Generate access keyy
 123                 String accessKey = null;
 124
 125                 // Default is found
 126                 boolean isFound = true;
 127
 128                 // Is the number used?
 129                 while (isFound) {
 130                         // Both number parts
 131                         String randString = String.format("%s:%s:%s", Long.toHexString(Math.round(Math.random() * 1_000_000)), em, customer.getCustomerNumber());
 132
 133                         // Generate access key, use SHA512 hashing and BASE64-encoding for strong key generation
 134                         accessKey = Base64.encodeBase64String(Sha2Crypt.sha512Crypt(randString.getBytes()).getBytes()).substring(0, 100);
 135
 136                         // Try this
 137                         try {
 138                                 // Get reference
 139                                 orderable = em.getReference(ShopOrder.class, accessKey);
 140                         } catch (final EntityNotFoundException ex) {
 141                                 // Not found, so abort loop here
 142                                 isFound = false;
 143                         }
 144                 }
 145
 146                 // Trace message
 147                 // TODO: utils.getLogger().logTrace(MessageFormat.format("generateAccessKey: accessKey={0} - EXIT!", accessKey));
 148                 // Found one
 149                 return accessKey;
 150         }
 151 }