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.Base64;
  26 import java.util.Iterator;
  27 import java.util.List;
  28 import java.util.StringTokenizer;
  29 import org.mxchange.addressbook.contact.Contact;
  30 import org.mxchange.addressbook.contact.Gender;
  31 import org.mxchange.addressbook.contact.book.BookContact;
  32 import org.mxchange.addressbook.contact.user.UserContact;
  33 import org.mxchange.addressbook.database.backend.BaseDatabaseBackend;
  34 import org.mxchange.addressbook.database.storage.Storeable;
  35 import org.mxchange.addressbook.database.storage.csv.StoreableCsv;
  36 import org.mxchange.addressbook.exceptions.BadTokenException;
  37
  38 /**
  39  * A database backend with CSV file as storage implementation
  40  *
  41  * @author Roland Haeder
  42  */
  43 public class CsvDatabaseBackend extends BaseDatabaseBackend implements CsvBackend {
  44
  45         /**
  46          * Output stream for this storage engine
  47          */
  48         private RandomAccessFile storageFile;
  49
  50         /**
  51          * Constructor with table name
  52          *
  53          * @param tableName Name of "table"
  54          */
  55         public CsvDatabaseBackend (final String tableName) {
  56                 // Debug message
  57                 this.getLogger().debug(MessageFormat.format("Trying to initialize table {0} ...", tableName));
  58
  59                 // Set table name here, too
  60                 this.setTableName(tableName);
  61
  62                 // Construct file name
  63                 String fileName = String.format("data/table_%s.b64", tableName);
  64
  65                 // Debug message
  66                 this.getLogger().debug(MessageFormat.format("Trying to open file {0} ...", fileName));
  67
  68                 try {
  69                         // Try to initialize the storage (file instance)
  70                         this.storageFile = new RandomAccessFile(fileName, "rw");
  71                 } catch (final FileNotFoundException ex) {
  72                         // Did not work
  73                         this.getLogger().error(MessageFormat.format("File {0} cannot be opened: {1}", fileName, ex.toString()));
  74                         System.exit(1);
  75                 }
  76
  77                 // Output message
  78                 this.getLogger().debug(MessageFormat.format("Database for {0} has been initialized.", tableName));
  79         }
  80
  81         /**
  82          * Gets an iterator for contacts
  83          *
  84          * @return Iterator for contacts
  85          * @throws org.mxchange.addressbook.exceptions.BadTokenException If the
  86          * underlaying method has found an invalid token
  87          */
  88         @Override
  89         public Iterator<Contact> contactIterator () throws BadTokenException {
  90                 /*
  91                  * Then read the file into RAM (yes, not perfect for >1000 entries ...)
  92                  * and get a List back.
  93                  */
  94                 List<Contact> list = this.readContactList();
  95
  96                 // Get iterator from list and return it
  97                 return list.iterator();
  98         }
  99
 100         /**
 101          * Shuts down this backend
 102          */
 103         @Override
 104         public void doShutdown () {
 105                 try {
 106                         // Close file
 107                         this.getStorageFile().close();
 108                 } catch (final IOException ex) {
 109                         this.getLogger().catching(ex);
 110                         System.exit(1);
 111                 }
 112         }
 113
 114         /**
 115          * Get length of underlaying file
 116          *
 117          * @return Length of underlaying file
 118          */
 119         @Override
 120         public long length () {
 121                 long length = 0;
 122
 123                 try {
 124                         length = this.getStorageFile().length();
 125                         this.getLogger().debug(MessageFormat.format("length={0}", length));
 126                 } catch (final IOException ex) {
 127                         // Length cannot be determined
 128                         this.getLogger().catching(ex);
 129                         System.exit(1);
 130                 }
 131
 132                 // Return result
 133                 this.getLogger().trace(MessageFormat.format("length={0} : EXIT!", length));
 134                 return length;
 135         }
 136
 137         /**
 138          * Rewinds backend
 139          */
 140         @Override
 141         public void rewind () {
 142                 this.getLogger().trace("CALLED!");
 143
 144                 try {
 145                         // Rewind underlaying database file
 146                         this.getStorageFile().seek(0);
 147                 } catch (final IOException ex) {
 148                         this.getLogger().catching(ex);
 149                         System.exit(1);
 150                 }
 151
 152                 this.getLogger().trace("EXIT!");
 153         }
 154
 155         /**
 156          * Stores given object by "visiting" it
 157          *
 158          * @param object An object implementing Storeable
 159          * @throws java.io.IOException From "inner" class
 160          */
 161         @Override
 162         public void store (final Storeable object) throws IOException {
 163                 // Make sure the instance is there (DataOutput flawor)
 164                 assert (this.storageFile instanceof DataOutput);
 165
 166                 // Try to cast it, this will fail if the interface is not implemented
 167                 StoreableCsv csv = (StoreableCsv) object;
 168
 169                 // Now get a string from the object that needs to be stored
 170                 String str = csv.getCsvStringFromStoreableObject();
 171
 172                 // Debug message
 173                 this.getLogger().debug(MessageFormat.format("str({0})={1}", str.length(), str));
 174
 175                 // Encode line in BASE-64
 176                 byte[] encoded = Base64.getEncoder().encode(str.trim().getBytes());
 177
 178                 // The string is now a valid CSV string
 179                 this.getStorageFile().write(encoded);
 180         }
 181
 182         /**
 183          * Adds given contact to list
 184          *
 185          * @param contact Contact instance to add
 186          * @param list List instance
 187          */
 188         private void addContactToList (final Contact contact, final List<Contact> list) {
 189                 // No null here
 190                 if (contact == null) {
 191                         // Throw exception
 192                         throw new NullPointerException("contact is null");
 193                 } else if (list == null) {
 194                         // Throw exception
 195                         throw new NullPointerException("list is null");
 196                 }
 197
 198                 // Debug message
 199                 this.getLogger().debug(MessageFormat.format("contact={0}", contact));
 200
 201                 // Is the contact read?
 202                 if (contact instanceof Contact) {
 203                         // Then add it
 204                         boolean added = list.add(contact);
 205
 206                         // Debug message
 207                         this.getLogger().debug(MessageFormat.format("contact={0} added={1}", contact, added));
 208
 209                         // Has it been added?
 210                         if (!added) {
 211                                 // Not added
 212                                 this.getLogger().warn("Contact object has not been added.");
 213                         }
 214                 }
 215         }
 216
 217         /**
 218          * Returns storage file
 219          *
 220          * @return Storage file instance
 221          */
 222         private RandomAccessFile getStorageFile () {
 223                 return this.storageFile;
 224         }
 225
 226         /**
 227          * Checks whether end of file has been reached
 228          *
 229          * @return Whether lines are left to read
 230          */
 231         private boolean isEndOfFile () {
 232                 // Default is EOF
 233                 boolean isEof = true;
 234
 235                 try {
 236                         isEof = (this.getStorageFile().getFilePointer() >= this.length());
 237                 } catch (final IOException ex) {
 238                         // Length cannot be determined
 239                         this.getLogger().catching(ex);
 240                 }
 241
 242                 // Return status
 243                 this.getLogger().trace(MessageFormat.format("isEof={0} : EXIT!", isEof));
 244                 return isEof;
 245         }
 246
 247         /**
 248          * Reads the database file, if available, and adds all read lines into the
 249          * list.
 250          *
 251          * @return A list with Contact instances
 252          */
 253         private List<Contact> readContactList () throws BadTokenException {
 254                 this.getLogger().trace("CALLED!");
 255
 256                 // First rewind
 257                 this.rewind();
 258
 259                 // Get file size and divide it by 140 (possible average length of one line)
 260                 int lines = Math.round(this.length() / 140 + 0.5f);
 261
 262                 // Debug message
 263                 this.getLogger().debug(MessageFormat.format("lines={0}", lines));
 264
 265         // Instance list
 266                 // @TODO The maximum length could be guessed from file size?
 267                 List<Contact> list = new ArrayList<>(lines);
 268
 269                 // Init variables
 270                 StringTokenizer tokenizer;
 271                 String line;
 272
 273                 // Init A lot variables
 274                 Long num = null;
 275                 Boolean bool = null;
 276                 Gender gender = null;
 277                 int count = 0;
 278                 Contact contact = null;
 279
 280                 // Read all lines
 281                 while (!this.isEndOfFile()) {
 282                         // Then read a line
 283                         line = this.readLine();
 284
 285                         // Debug message
 286                         this.getLogger().debug(MessageFormat.format("line={0}", line));
 287
 288                         // Then tokenize it
 289                         // @TODO Move this into separate method
 290                         tokenizer = new StringTokenizer(line, ";");
 291
 292                         // Reset variables
 293                         count = 0;
 294                         contact = null;
 295
 296                         // The tokens are now available, so get all
 297                         while (tokenizer.hasMoreElements()) {
 298                                 // Reset variables
 299                                 num = null;
 300                                 bool = null;
 301
 302                                 // Get next token
 303                                 String token = tokenizer.nextToken();
 304
 305                                 // If char " is at pos 2 (0,1,2), then cut it of there
 306                                 if ((token.charAt(0) != '"') && (token.charAt(2) == '"')) {
 307                                         // UTF-8 writer characters found
 308                                         token = token.substring(2);
 309                                 }
 310
 311                                 // Debug message
 312                                 this.getLogger().debug(MessageFormat.format("token={0}", token));
 313
 314                                 // Verify token, it must have double-quotes on each side
 315                                 if ((!token.startsWith("\"")) || (!token.endsWith("\""))) {
 316                                         // Something bad was read
 317                                         throw new BadTokenException(MessageFormat.format("Token {0} at position {1} has not double-quotes on both ends.", token, count));
 318                                 }
 319
 320                                 // All fine, so remove it
 321                                 String strippedToken = token.substring(1, token.length() - 1);
 322
 323                                 // Is the string's content "null"?
 324                                 if (strippedToken.equals("null")) {
 325                                         // Debug message
 326                                         this.getLogger().debug(MessageFormat.format("strippedToken={0} - NULL!", strippedToken));
 327
 328                                         // This needs to be set to null
 329                                         strippedToken = null;
 330                                 }
 331
 332                                 // Debug message
 333                                 this.getLogger().debug(MessageFormat.format("strippedToken={0}", strippedToken));
 334
 335                                 // Now, let's try a number check, if no null
 336                                 if (strippedToken != null) {
 337                                         // Okay, no null, maybe the string bears a decimal number?
 338                                         try {
 339                                                 num = Long.valueOf(strippedToken);
 340
 341                                                 // Debug message
 342                                                 this.getLogger().debug(MessageFormat.format("strippedToken={0} - NUMBER!", strippedToken));
 343                                         } catch (final NumberFormatException ex) {
 344                                                 // No number, then set default
 345                                                 num = null;
 346                                         }
 347                                 }
 348
 349                                 // Now, let's try a boolean check, if no null
 350                                 if ((strippedToken != null) && (num == null) && ((strippedToken.equals("true")) || (strippedToken.equals("false")))) {
 351                                         // Debug message
 352                                         this.getLogger().debug(MessageFormat.format("strippedToken={0} - BOOLEAN!", strippedToken));
 353
 354                                         // parseBoolean() is relaxed, so no exceptions
 355                                         bool = Boolean.valueOf(strippedToken);
 356                                 }
 357
 358                                 // Debug message
 359                                 this.getLogger().debug(MessageFormat.format("strippedToken={0},num={1},bool={2}", strippedToken, num, bool));
 360
 361                                 // Now, let's try a gender check, if no null
 362                                 if ((strippedToken != null) && (num == null) && (bool == null) && ((strippedToken.equals("M")) || (strippedToken.equals("F")) || (strippedToken.equals("C")))) {
 363                                         // Get first character
 364                                         gender = Gender.fromChar(strippedToken.charAt(0));
 365
 366                                         // Debug message
 367                                         this.getLogger().debug(MessageFormat.format("strippedToken={0},gender={1}", strippedToken, gender));
 368
 369                                         // This instance must be there
 370                                         assert (gender instanceof Gender) : "gender is not set by Gender.fromChar(" + strippedToken + ")";
 371                                 }
 372
 373                                 // Now it depends on the counter which position we need to check
 374                                 switch (count) {
 375                                         case 0: // isOwnContact
 376                                                 assert ((bool instanceof Boolean));
 377
 378                                                 // Debug message
 379                                                 this.getLogger().debug(MessageFormat.format("bool={0}", bool));
 380
 381                                                 // Is it own contact?
 382                                                 if (true == bool) {
 383                                                         // Debug message
 384                                                         this.getLogger().debug("Creating UserContact object ...");
 385
 386                                                         // Own entry
 387                                                         contact = new UserContact();
 388                                                 } else {
 389                                                         // Debug message
 390                                                         this.getLogger().debug("Creating BookContact object ...");
 391
 392                                                         // Other contact
 393                                                         contact = new BookContact();
 394                                                 }
 395                                                 break;
 396
 397                                         case 1: // Gender
 398                                                 assert (contact instanceof Contact) : "First token was not boolean";
 399
 400                                                 // Update data
 401                                                 contact.updateNameData(gender, null, null, null);
 402                                                 break;
 403
 404                                         case 2: // Surname
 405                                                 assert (contact instanceof Contact) : "First token was not boolean";
 406                                                 assert (gender instanceof Gender) : "gender instance is not set";
 407
 408                                                 // Update data
 409                                                 contact.updateNameData(gender, strippedToken, null, null);
 410                                                 break;
 411
 412                                         case 3: // Family name
 413                                                 assert (contact instanceof Contact) : "First token was not boolean";
 414                                                 assert (gender instanceof Gender) : "gender instance is not set";
 415
 416                                                 // Update data
 417                                                 contact.updateNameData(gender, null, strippedToken, null);
 418                                                 break;
 419
 420                                         case 4: // Company name
 421                                                 assert (contact instanceof Contact) : "First token was not boolean";
 422                                                 assert (gender instanceof Gender) : "gender instance is not set";
 423
 424                                                 // Update data
 425                                                 contact.updateNameData(gender, null, null, strippedToken);
 426                                                 break;
 427
 428                                         case 5: // Street number
 429                                                 assert (contact instanceof Contact) : "First token was not boolean";
 430
 431                                                 // Update data
 432                                                 contact.updateAddressData(strippedToken, 0, null, null);
 433                                                 break;
 434
 435                                         case 6: // ZIP code
 436                                                 assert (contact instanceof Contact) : "First token was not boolean";
 437
 438                                                 // Update data
 439                                                 contact.updateAddressData(null, num, null, null);
 440                                                 break;
 441
 442                                         case 7: // City name
 443                                                 assert (contact instanceof Contact) : "First token was not boolean";
 444
 445                                                 // Update data
 446                                                 contact.updateAddressData(null, 0, strippedToken, null);
 447                                                 break;
 448
 449                                         case 8: // Country code
 450                                                 assert (contact instanceof Contact) : "First token was not boolean";
 451
 452                                                 // Update data
 453                                                 contact.updateAddressData(null, 0, null, strippedToken);
 454                                                 break;
 455
 456                                         case 9: // Phone number
 457                                                 assert (contact instanceof Contact) : "First token was not boolean";
 458
 459                                                 // Update data
 460                                                 contact.updateOtherData(strippedToken, null, null, null, null, null);
 461                                                 break;
 462
 463                                         case 10: // Fax number
 464                                                 assert (contact instanceof Contact) : "First token was not boolean";
 465
 466                                                 // Update data
 467                                                 contact.updateOtherData(null, strippedToken, null, null, null, null);
 468                                                 break;
 469
 470                                         case 11: // Cellphone number
 471                                                 assert (contact instanceof Contact) : "First token was not boolean";
 472
 473                                                 // Update data
 474                                                 contact.updateOtherData(null, null, strippedToken, null, null, null);
 475                                                 break;
 476
 477                                         case 12: // Email address
 478                                                 assert (contact instanceof Contact) : "First token was not boolean";
 479
 480                                                 // Update data
 481                                                 contact.updateOtherData(null, null, null, strippedToken, null, null);
 482                                                 break;
 483
 484                                         case 13: // Birthday
 485                                                 assert (contact instanceof Contact) : "First token was not boolean";
 486
 487                                                 // Update data
 488                                                 contact.updateOtherData(null, null, null, null, strippedToken, null);
 489                                                 break;
 490
 491                                         case 14: // Birthday
 492                                                 assert (contact instanceof Contact) : "First token was not boolean";
 493
 494                                                 // Update data
 495                                                 contact.updateOtherData(null, null, null, null, null, strippedToken);
 496                                                 break;
 497
 498                                         default: // New data entry
 499                                                 this.getLogger().warn(MessageFormat.format("Will not handle unknown data {0} at index {1}", strippedToken, count));
 500                                                 break;
 501                                 }
 502
 503                                 // Increment counter for next round
 504                                 count++;
 505                         }
 506
 507                         // The contact instance should be there now
 508                         assert(contact instanceof Contact) : "contact is not set: " + contact;
 509
 510                         // Add contact
 511                         this.addContactToList(contact, list);
 512                 }
 513
 514                 // Return finished list
 515                 this.getLogger().trace(MessageFormat.format("list.size()={0} : EXIT!", list.size()));
 516                 return list;
 517         }
 518
 519         /**
 520          * Reads a line from file base
 521          *
 522          * @return Read line from file
 523          */
 524         private String readLine () {
 525                 // Init input
 526                 String input = null;
 527
 528                 try {
 529                         String base64 = this.getStorageFile().readLine();
 530
 531                         // Decode BASE-64
 532                         byte[] decoded = Base64.getDecoder().decode(base64);
 533
 534                         // Convert to string
 535                         input = new String(decoded);
 536                 } catch (final IOException ex) {
 537                         this.getLogger().catching(ex);
 538                 }
 539
 540                 // Return read string or null
 541                 return input;
 542         }
 543 }