src/java/org/mxchange/pizzaapplication/database/frontend/category/PizzaCategoryDatabaseFrontend.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.pizzaapplication.database.frontend.category;
  18
  19 import java.io.IOException;
  20 import java.sql.ResultSet;
  21 import java.sql.SQLException;
  22 import java.text.MessageFormat;
  23 import java.util.Iterator;
  24 import java.util.Map;
  25 import org.mxchange.jcore.criteria.searchable.SearchCriteria;
  26 import org.mxchange.jcore.criteria.searchable.SearchableCritera;
  27 import org.mxchange.jcore.database.frontend.BaseDatabaseFrontend;
  28 import org.mxchange.jcore.database.result.DatabaseResult;
  29 import org.mxchange.jcore.database.result.Result;
  30 import org.mxchange.jcore.database.storage.Storeable;
  31 import org.mxchange.jcore.exceptions.BadTokenException;
  32 import org.mxchange.jcore.exceptions.CorruptedDatabaseFileException;
  33 import org.mxchange.jcore.exceptions.UnsupportedDatabaseBackendException;
  34 import org.mxchange.pizzaapplication.category.Category;
  35 import org.mxchange.pizzaapplication.category.product.ProductCategory;
  36 import org.mxchange.pizzaapplication.database.category.PizzaCategoryDatabaseConstants;
  37
  38 /**
  39  * Stores and retrieves Contact instances
  40  *
  41  * @author Roland Haeder
  42  */
  43 public class PizzaCategoryDatabaseFrontend extends BaseDatabaseFrontend implements CategoryFrontend {
  44         /**
  45          * Default constrcutor
  46          * @throws org.mxchange.jcore.exceptions.UnsupportedDatabaseBackendException If the configured backend is not supported
  47          * @throws java.sql.SQLException If any SQL error occurs
  48          */
  49         public PizzaCategoryDatabaseFrontend () throws UnsupportedDatabaseBackendException, SQLException {
  50                 // Trace message
  51                 this.getLogger().trace("CALLED!"); //NOI18N
  52
  53                 // Set "table" name
  54                 this.setTableName("category"); //NOI18N
  55
  56                 // Initalize backend
  57                 this.initBackend();
  58         }
  59
  60         /**
  61          * Adds given category title as new category, parent may be null if not selected.
  62          *
  63          * @param title Title of category
  64          * @param parent Parent id or null if not selected
  65          */
  66         @Override
  67         public void addCategory (final String title, final Integer parent) throws SQLException, IOException {
  68                 // Trace message
  69                 this.getLogger().trace(MessageFormat.format("title={0},parent={1} - CALLED!", title, parent));
  70
  71                 // Title should not be null
  72                 if (title == null) {
  73                         // Abort here
  74                         throw new NullPointerException("title is null");
  75                 }
  76
  77                 // Clear dataset from previous usage
  78                 this.clearDataSet();
  79
  80                 // Add title and parent
  81                 this.addToDataSet(PizzaCategoryDatabaseConstants.COLUMN_TITLE, title);
  82                 this.addToDataSet(PizzaCategoryDatabaseConstants.COLUMN_PARENT, parent);
  83
  84                 // Handle this over to the backend
  85                 Result<? extends Storeable> result = this.doInsertDataSet();
  86
  87                 // Debug message
  88                 this.getLogger().debug(MessageFormat.format("result={0}", result));
  89
  90                 // Trace message
  91                 this.getLogger().trace("EXIT!");
  92         }
  93
  94         /**
  95          * Shuts down the database layer
  96          * @throws java.sql.SQLException If an SQL error occurs
  97          * @throws java.io.IOException If any IO error occurs
  98          */
  99         @Override
 100         public void doShutdown () throws SQLException, IOException {
 101                 // Trace message
 102                 this.getLogger().trace("CALLED!"); //NOI18N
 103
 104                 // Shutdown backend
 105                 this.getBackend().doShutdown();
 106
 107                 // Trace message
 108                 this.getLogger().trace("EXIT!"); //NOI18N
 109         }
 110
 111         /**
 112          * Depending on column, an empty value may be converted to null
 113          *
 114          * @param key Key to check
 115          * @param value Value to check
 116          * @return Possible previous value or null
 117          */
 118         @Override
 119         public Object emptyStringToNull (final String key, final Object value) {
 120                 // Trace message
 121                 this.getLogger().trace(MessageFormat.format("key={0},value={1} - CALLED!", key, value));
 122
 123                 // Copy value
 124                 Object v = value;
 125
 126                 // Is the value empty?
 127                 if ((value instanceof String) && ("".equals(value))) {
 128                         // This value may need to be changed
 129                         switch (key) {
 130                                 case PizzaCategoryDatabaseConstants.COLUMN_PARENT: // Convert this
 131                                         v = null;
 132                                         break;
 133                         }
 134                 }
 135
 136                 // Trace message
 137                 this.getLogger().trace(MessageFormat.format("v={0} - EXIT!", v));
 138
 139                 // Return it
 140                 return v;
 141         }
 142
 143         @Override
 144         @SuppressWarnings ("unchecked")
 145         public Iterator<Category> getCategories () throws IOException, BadTokenException, SQLException, CorruptedDatabaseFileException {
 146                 // Trace message
 147                 this.getLogger().trace("CALLED!"); //NOI18N
 148
 149                 // Instance search criteria
 150                 SearchableCritera critera = new SearchCriteria();
 151
 152                 // Run the query
 153                 Result<? extends Storeable> result = this.getBackend().doSelectByCriteria(critera);
 154
 155                 // Debug message
 156                 this.getLogger().debug(MessageFormat.format("result={0}", result)); //NOI18N
 157
 158                 // Get iterator
 159                 Iterator<?> iterator = result.iterator();
 160
 161                 // Trace message
 162                 this.getLogger().trace(MessageFormat.format("iterator={0} - EXIT!", iterator)); //NOI18N
 163
 164                 // Get iterator and return it
 165                 return (Iterator<Category>) iterator;
 166         }
 167
 168         /**
 169          * Gets a Result back from given ResultSet instance
 170          *
 171          * @param resultSet ResultSet instance from SQL driver
 172          * @return A typorized Result instance
 173          * @throws java.sql.SQLException If any SQL error occurs
 174          */
 175         @Override
 176         public Result<? extends Storeable> getResultFromSet (final ResultSet resultSet) throws SQLException {
 177                 // Trace message
 178                 this.getLogger().trace(MessageFormat.format("resultSet={0} - CALLED!", resultSet));
 179
 180                 // Init result instance
 181                 Result<? extends Storeable> result = new DatabaseResult();
 182
 183                 // Reset result set before first row
 184                 resultSet.beforeFirst();
 185
 186                 // "Walk" through all entries
 187                 while (resultSet.next()) {
 188                         // Get id, title and parent id
 189                         Integer id = resultSet.getInt(PizzaCategoryDatabaseConstants.COLUMN_ID);
 190                         String title = resultSet.getString(PizzaCategoryDatabaseConstants.COLUMN_TITLE);
 191                         Integer parent = resultSet.getInt(PizzaCategoryDatabaseConstants.COLUMN_PARENT);
 192
 193                         // Debug message
 194                         this.getLogger().debug(MessageFormat.format("id={0},title={1},parent={2}", id, title, parent));
 195
 196                         // Instance new object
 197                         Category category = new ProductCategory(id, title, parent);
 198
 199                         // Debug log
 200                         this.getLogger().debug(MessageFormat.format("category={0}", category));
 201
 202                         // Add it to result
 203                         result.add(category);
 204                 }
 205
 206                 // Trace message
 207                 this.getLogger().trace(MessageFormat.format("result({0})={1} - EXIT!", result.size(), result));
 208
 209                 // Return result
 210                 return result;
 211         }
 212
 213         /**
 214          * Checks if given category title is already used
 215          *
 216          * @param title Title to check
 217          * @return Whether the title has been used
 218          */
 219         @Override
 220         public boolean isCategoryTitleUsed (final String title) throws IOException, SQLException, BadTokenException, CorruptedDatabaseFileException {
 221                 // Trace message
 222                 this.getLogger().trace(MessageFormat.format("title={0} - CALLED!", title));
 223
 224                 // Get search criteria
 225                 SearchableCritera criteria = new SearchCriteria();
 226
 227                 // Add criteria
 228                 criteria.addCriteria(PizzaCategoryDatabaseConstants.COLUMN_TITLE, title);
 229
 230                 // Only one entry is find
 231                 criteria.setLimit(1);
 232
 233                 // Run it on backend
 234                 Result<? extends Storeable> result = this.getBackend().doSelectByCriteria(criteria);
 235
 236                 // Debug log
 237                 this.getLogger().debug(MessageFormat.format("result({0}={1}", result, result.size()));
 238
 239                 // Now check size of the result
 240                 boolean isFound = (result.size() == 1);
 241
 242                 // Trace message
 243                 this.getLogger().trace(MessageFormat.format("isFound={0} - EXIT!", isFound));
 244
 245                 // Return it
 246                 return isFound;
 247         }
 248
 249         /**
 250          * Converts the given map into a Storeable instance, depending on which class implements it. All
 251          * keys are being interpreted as class fields/attributes and their respective setters are being searched for. As
 252          * this method may fail to find one or access it, this method throws some exception.
 253          *
 254          * @param map Map instance to convert to Storeable
 255          * @return An instance of a Storeable implementation
 256          */
 257         @Override
 258         public Storeable toStoreable (final Map<String, String> map) {
 259                 // Trace message
 260                 this.getLogger().trace("map=" + map + " - CALLED!");
 261
 262                 // Is map null?
 263                 if (map == null) {
 264                         // Is null
 265                         throw new NullPointerException("map is null");
 266                 } else if (map.isEmpty()) {
 267                         // Map is empty
 268                         throw new IllegalArgumentException("map is empty.");
 269                 }
 270
 271                 // Debug message
 272                 this.getLogger().debug("Has to handle " + map.size() + " entries");
 273
 274                 // Get iterator on all entries
 275                 Iterator<Map.Entry<String, String>> iterator = map.entrySet().iterator();
 276
 277                 // Init object instance
 278                 Storeable instance = new ProductCategory();
 279
 280                 // Iterate over all
 281                 while (iterator.hasNext()) {
 282                         // Get next entry
 283                         Map.Entry<String, String> entry = iterator.next();
 284
 285                         // Debug message
 286                         this.getLogger().debug("entry:" + entry.getKey() + "=" + entry.getValue());
 287
 288                         // Try to set value
 289                         instance.setValueFromColumn(entry.getKey(), entry.getValue());
 290                 }
 291
 292                 throw new UnsupportedOperationException("Not supported yet: map=" + map);
 293         }
 294 }