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