Addressbook/src/org/mxchange/addressbook/database/backend/csv/CsvDatabaseBackend.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.addressbook.database.backend.csv;
  18
  19 import java.io.DataOutput;
  20 import java.io.FileNotFoundException;
  21 import java.io.IOException;
  22 import java.io.RandomAccessFile;
  23 import java.text.MessageFormat;
  24 import java.util.ArrayList;
  25 import java.util.Iterator;
  26 import java.util.List;
  27 import java.util.StringTokenizer;
  28 import org.mxchange.addressbook.contact.Contact;
  29 import org.mxchange.addressbook.contact.book.BookContact;
  30 import org.mxchange.addressbook.contact.user.UserContact;
  31 import org.mxchange.addressbook.database.backend.BaseDatabaseBackend;
  32 import org.mxchange.addressbook.database.storage.Storeable;
  33 import org.mxchange.addressbook.database.storage.csv.StoreableCsv;
  34 import org.mxchange.addressbook.exceptions.BadTokenException;
  35
  36 /**
  37  * A database backend with CSV file as storage implementation
  38  *
  39  * @author Roland Haeder
  40  */
  41 public class CsvDatabaseBackend extends BaseDatabaseBackend implements CsvBackend {
  42
  43         /**
  44          * Output stream for this storage engine
  45          */
  46         private RandomAccessFile storageFile;
  47
  48         /**
  49          * Constructor with table name
  50          *
  51          * @param tableName Name of "table"
  52          */
  53         public CsvDatabaseBackend (final String tableName) {
  54                 // Debug message
  55                 this.getLogger().debug(MessageFormat.format("Trying to initialize table {0} ...", tableName));
  56
  57                 // Set table name here, too
  58                 this.setTableName(tableName);
  59
  60                 // Construct file name
  61                 String fileName = String.format("data/table_%s.csv", tableName);
  62
  63                 // Debug message
  64                 this.getLogger().debug(MessageFormat.format("Trying to open file {0} ...", fileName));
  65
  66                 try {
  67                         // Try to initialize the storage (file instance)
  68                         this.storageFile = new RandomAccessFile(fileName, "rw");
  69                 } catch (final FileNotFoundException ex) {
  70                         // Did not work
  71                         this.getLogger().error(MessageFormat.format("File {0} cannot be opened: {1}", fileName, ex.toString()));
  72                         System.exit(1);
  73                 }
  74
  75                 // Output message
  76                 this.getLogger().debug(MessageFormat.format("Database for {0} has been initialized.", tableName));
  77         }
  78
  79         /**
  80          * Gets an iterator for contacts
  81          *
  82          * @return Iterator for contacts
  83          * @throws org.mxchange.addressbook.exceptions.BadTokenException If the
  84          * underlaying method has found an invalid token
  85          */
  86         @Override
  87         public Iterator<Contact> contactIterator () throws BadTokenException {
  88                 /*
  89                  * Then read the file into RAM (yes, not perfect for >1000 entries ...)
  90                  * and get a List back.
  91                  */
  92                 List<Contact> list = this.readContactList();
  93
  94                 // Get iterator from list and return it
  95                 return list.iterator();
  96         }
  97
  98         /**
  99          * Shuts down this backend
 100          */
 101         @Override
 102         public void doShutdown () {
 103                 try {
 104                         // Close file
 105                         this.getStorageFile().close();
 106                 } catch (final IOException ex) {
 107                         this.getLogger().catching(ex);
 108                         System.exit(1);
 109                 }
 110         }
 111
 112         /**
 113          * Get length of underlaying file
 114          *
 115          * @return Length of underlaying file
 116          */
 117         @Override
 118         public long length () {
 119                 long length = 0;
 120
 121                 try {
 122                         length = this.getStorageFile().length();
 123                         this.getLogger().debug(MessageFormat.format("length={0}", length));
 124                 } catch (final IOException ex) {
 125                         // Length cannot be determined
 126                         this.getLogger().catching(ex);
 127                         System.exit(1);
 128                 }
 129
 130                 // Return result
 131                 this.getLogger().trace(MessageFormat.format("length={0} : EXIT!", length));
 132                 return length;
 133         }
 134
 135         /**
 136          * Rewinds backend
 137          */
 138         @Override
 139         public void rewind () {
 140                 this.getLogger().trace("CALLED!");
 141
 142                 try {
 143                         // Rewind underlaying database file
 144                         this.getStorageFile().seek(0);
 145                 } catch (final IOException ex) {
 146                         this.getLogger().catching(ex);
 147                         System.exit(1);
 148                 }
 149
 150                 this.getLogger().trace("EXIT!");
 151         }
 152
 153         /**
 154          * Stores given object by "visiting" it
 155          *
 156          * @param object An object implementing Storeable
 157          * @throws java.io.IOException From "inner" class
 158          */
 159         @Override
 160         public void store (final Storeable object) throws IOException {
 161                 // Make sure the instance is there (DataOutput flawor)
 162                 assert (this.storageFile instanceof DataOutput);
 163
 164                 // Try to cast it, this will fail if the interface is not implemented
 165                 StoreableCsv csv = (StoreableCsv) object;
 166
 167                 // Now get a string from the object that needs to be stored
 168                 String str = csv.getCsvStringFromStoreableObject();
 169
 170                 // Debug message
 171                 this.getLogger().debug(MessageFormat.format("str({0})={1}", str.length(), str));
 172
 173                 // The string is now a valid CSV string
 174                 this.getStorageFile().writeBytes(str);
 175         }
 176
 177         /**
 178          * Adds given contact to list
 179          *
 180          * @param contact Contact instance to add
 181          * @param list List instance
 182          */
 183         private void addContactToList (final Contact contact, final List<Contact> list) {
 184                 // Debug message
 185                 this.getLogger().debug(MessageFormat.format("contact={0}", contact));
 186
 187                 // Is the contact read?
 188                 if (contact instanceof Contact) {
 189                         // Then add it
 190                         boolean added = list.add(contact);
 191
 192                         // Debug message
 193                         this.getLogger().debug(MessageFormat.format("contact={0} added={1}", contact, added));
 194
 195                         // Has it been added?
 196                         if (!added) {
 197                                 // Not added
 198                                 this.getLogger().warn("Contact object has not been added.");
 199                         }
 200                 }
 201         }
 202
 203         /**
 204          * Returns storage file
 205          *
 206          * @return Storage file instance
 207          */
 208         private RandomAccessFile getStorageFile () {
 209                 return this.storageFile;
 210         }
 211
 212         /**
 213          * Checks whether end of file has been reached
 214          *
 215          * @return Whether lines are left to read
 216          */
 217         private boolean isEndOfFile () {
 218                 // Default is EOF
 219                 boolean isEof = true;
 220
 221                 try {
 222                         isEof = (this.getStorageFile().getFilePointer() >= this.length());
 223                 } catch (final IOException ex) {
 224                         // Length cannot be determined
 225                         this.getLogger().catching(ex);
 226                 }
 227
 228                 // Return status
 229                 this.getLogger().trace(MessageFormat.format("isEof={0} : EXIT!", isEof));
 230                 return isEof;
 231         }
 232
 233         /**
 234          * Reads the database file, if available, and adds all read lines into the
 235          * list.
 236          *
 237          * @return A list with Contact instances
 238          */
 239         private List<Contact> readContactList () throws BadTokenException {
 240                 this.getLogger().trace("CALLED!");
 241
 242                 // First rewind
 243                 this.rewind();
 244
 245                 // Get file size and divide it by 140 (possible average length of one line)
 246                 int lines = Math.round(this.length() / 140 + 0.5f);
 247
 248                 // Debug message
 249                 this.getLogger().debug(MessageFormat.format("lines={0}", lines));
 250
 251         // Instance list
 252                 // @TODO The maximum length could be guessed from file size?
 253                 List<Contact> list = new ArrayList<>(lines);
 254
 255                 // Init variables
 256                 StringTokenizer tokenizer;
 257                 String line;
 258
 259                 // Read all lines
 260                 while (!this.isEndOfFile()) {
 261                         // Then read a line
 262                         line = this.readLine();
 263
 264                         // Debug message
 265                         this.getLogger().debug(MessageFormat.format("line={0}", line));
 266
 267             // Then tokenize it
 268                         // @TODO Move this into separate method
 269                         tokenizer = new StringTokenizer(line, ";");
 270
 271                         // Count round
 272                         int count = 0;
 273
 274                         // Init contact object
 275                         Contact contact = null;
 276
 277                         // The tokens are now available, so get all
 278                         while (tokenizer.hasMoreElements()) {
 279                                 // Get next token
 280                                 String token = tokenizer.nextToken();
 281
 282                                 // Debug message
 283                                 this.getLogger().debug(MessageFormat.format("token={0}", token));
 284
 285                                 // Verify token, it must have double-quotes on each side
 286                                 if ((!token.startsWith("\"")) || (!token.endsWith("\""))) {
 287                                         // Something bad was read
 288                                         throw new BadTokenException(MessageFormat.format("Token {0} has not double-quotes on both ends.", token));
 289                                 }
 290
 291                                 // All fine, so remove it
 292                                 String strippedToken = token.substring(1, token.length() - 1);
 293
 294                                 // Is the string's content "null"?
 295                                 if (strippedToken.equals("null")) {
 296                                         // Debug message
 297                                         this.getLogger().debug(MessageFormat.format("strippedToken={0} - NULL!", strippedToken));
 298
 299                                         // This needs to be set to null
 300                                         strippedToken = null;
 301                                 }
 302
 303                                 // Debug message
 304                                 this.getLogger().debug(MessageFormat.format("strippedToken={0}", strippedToken));
 305
 306                                 // Init number/string data values
 307                                 String strData = strippedToken;
 308                                 Long num = null;
 309                                 Boolean bool = null;
 310                                 char gender = '?';
 311
 312                                 // Now, let's try a number check, if no null
 313                                 if (strippedToken != null) {
 314                                         // Okay, no null, maybe the string bears a decimal number?
 315                                         try {
 316                                                 num = Long.valueOf(strippedToken);
 317
 318                                                 // Debug message
 319                                                 this.getLogger().debug(MessageFormat.format("strippedToken={0} - NUMBER!", strippedToken));
 320                                         } catch (final NumberFormatException ex) {
 321                                                 // No number, then set default
 322                                                 num = null;
 323                                         }
 324                                 }
 325
 326                                 // Now, let's try a boolean check, if no null
 327                                 if ((strippedToken != null) && (num == null) && ((strippedToken.equals("true")) || (strippedToken.equals("false")))) {
 328                                         // Debug message
 329                                         this.getLogger().debug(MessageFormat.format("strippedToken={0} - BOOLEAN!", strippedToken));
 330
 331                                         // parseBoolean() is relaxed, so no exceptions
 332                                         bool = Boolean.valueOf(strippedToken);
 333                                 }
 334
 335                                 // Now, let's try a boolean check, if no null
 336                                 if ((strippedToken != null) && (num == null) && (bool == null) && ((strippedToken.equals("M")) || (strippedToken.equals("F")) || (strippedToken.equals("C")))) {
 337                                         // Get first character
 338                                         gender = strippedToken.charAt(0);
 339                                 }
 340
 341                                 // Now it depends on the counter which position we need to check
 342                                 switch (count) {
 343                                         case 0: // isOwnContact
 344                                                 assert ((bool instanceof Boolean));
 345
 346                                                 // Debug message
 347                                                 this.getLogger().debug(MessageFormat.format("bool={0}", bool));
 348
 349                                                 // Is it own contact?
 350                                                 if (true == bool) {
 351                                                         // Debug message
 352                                                         this.getLogger().debug("Creating UserContact object ...");
 353
 354                                                         // Own entry
 355                                                         contact = new UserContact();
 356                                                 } else {
 357                                                         // Debug message
 358                                                         this.getLogger().debug("Creating BookContact object ...");
 359
 360                                                         // Other contact
 361                                                         contact = new BookContact();
 362                                                 }
 363                                                 break;
 364
 365                                         case 1: // Gender
 366                                                 assert (contact instanceof Contact) : "First token was not boolean";
 367                                                 assert (gender != '?') : "Gender is not detected.";
 368
 369                                                 // Update data
 370                                                 contact.updateNameData(gender, null, null, null);
 371                                                 break;
 372
 373                                         case 2: // Surname
 374                                                 assert (contact instanceof Contact) : "First token was not boolean";
 375                                                 assert (gender != '?') : "Gender is not detected.";
 376
 377                                                 // Update data
 378                                                 contact.updateNameData(gender, strippedToken, null, null);
 379                                                 break;
 380
 381                                         case 3: // Family name
 382                                                 assert (contact instanceof Contact) : "First token was not boolean";
 383                                                 assert (gender != '?') : "Gender is not detected.";
 384
 385                                                 // Update data
 386                                                 contact.updateNameData(gender, null, strippedToken, null);
 387                                                 break;
 388
 389                                         case 4: // Company name
 390                                                 assert (contact instanceof Contact) : "First token was not boolean";
 391                                                 assert (gender != '?') : "Gender is not detected.";
 392
 393                                                 // Update data
 394                                                 contact.updateNameData(gender, null, null, strippedToken);
 395                                                 break;
 396
 397                                         case 5: // Street number
 398                                                 assert (contact instanceof Contact) : "First token was not boolean";
 399
 400                                                 // Update data
 401                                                 contact.updateAddressData(strippedToken, 0, null, null);
 402                                                 break;
 403
 404                                         case 6: // ZIP code
 405                                                 assert (contact instanceof Contact) : "First token was not boolean";
 406
 407                                                 // Update data
 408                                                 contact.updateAddressData(null, num, null, null);
 409                                                 break;
 410
 411                                         case 7: // City name
 412                                                 assert (contact instanceof Contact) : "First token was not boolean";
 413
 414                                                 // Update data
 415                                                 contact.updateAddressData(null, 0, strippedToken, null);
 416                                                 break;
 417
 418                                         case 8: // Country code
 419                                                 assert (contact instanceof Contact) : "First token was not boolean";
 420
 421                                                 // Update data
 422                                                 contact.updateAddressData(null, 0, null, strippedToken);
 423                                                 break;
 424
 425                                         case 9: // Phone number
 426                                                 assert (contact instanceof Contact) : "First token was not boolean";
 427
 428                                                 // Update data
 429                                                 contact.updateOtherData(strippedToken, null, null, null, null, null);
 430                                                 break;
 431
 432                                         case 10: // Fax number
 433                                                 assert (contact instanceof Contact) : "First token was not boolean";
 434
 435                                                 // Update data
 436                                                 contact.updateOtherData(null, strippedToken, null, null, null, null);
 437                                                 break;
 438
 439                                         case 11: // Cellphone number
 440                                                 assert (contact instanceof Contact) : "First token was not boolean";
 441
 442                                                 // Update data
 443                                                 contact.updateOtherData(null, null, strippedToken, null, null, null);
 444                                                 break;
 445
 446                                         case 12: // Email address
 447                                                 assert (contact instanceof Contact) : "First token was not boolean";
 448
 449                                                 // Update data
 450                                                 contact.updateOtherData(null, null, null, strippedToken, null, null);
 451                                                 break;
 452
 453                                         case 13: // Birthday
 454                                                 assert (contact instanceof Contact) : "First token was not boolean";
 455
 456                                                 // Update data
 457                                                 contact.updateOtherData(null, null, null, null, strippedToken, null);
 458                                                 break;
 459
 460                                         case 14: // Birthday
 461                                                 assert (contact instanceof Contact) : "First token was not boolean";
 462
 463                                                 // Update data
 464                                                 contact.updateOtherData(null, null, null, null, null, strippedToken);
 465                                                 break;
 466
 467                                         default: // New data entry
 468                                                 this.getLogger().warn(MessageFormat.format("Will not handle unknown data {0} at index {1}", strippedToken, count));
 469                                                 break;
 470                                 }
 471
 472                                 // Increment counter for next round
 473                                 count++;
 474                         }
 475
 476                         // Add contact
 477                         this.addContactToList(contact, list);
 478                 }
 479
 480                 // Return finished list
 481                 this.getLogger().trace(MessageFormat.format("list.size()={0} : EXIT!", list.size()));
 482                 return list;
 483         }
 484
 485         /**
 486          * Reads a line from file base
 487          *
 488          * @return Read line from file
 489          */
 490         private String readLine () {
 491                 // Init input
 492                 String input = null;
 493
 494                 try {
 495                         input = this.getStorageFile().readLine();
 496                 } catch (final IOException ex) {
 497                         this.getLogger().catching(ex);
 498                 }
 499
 500                 // Return read string or null
 501                 return input;
 502         }
 503 }