| 1 | package be.nikiroo.utils.serial; |
| 2 | |
| 3 | import java.io.IOException; |
| 4 | import java.io.NotSerializableException; |
| 5 | import java.lang.reflect.Array; |
| 6 | import java.lang.reflect.Constructor; |
| 7 | import java.lang.reflect.Field; |
| 8 | import java.lang.reflect.Modifier; |
| 9 | import java.net.URL; |
| 10 | import java.util.ArrayList; |
| 11 | import java.util.HashMap; |
| 12 | import java.util.List; |
| 13 | import java.util.Map; |
| 14 | import java.util.UnknownFormatConversionException; |
| 15 | |
| 16 | import be.nikiroo.utils.Image; |
| 17 | |
| 18 | /** |
| 19 | * Small class to help with serialisation. |
| 20 | * <p> |
| 21 | * Note that we do not support inner classes (but we do support nested classes) |
| 22 | * and all objects require an empty constructor to be deserialised. |
| 23 | * <p> |
| 24 | * It is possible to add support to custom types (both the encoder and the |
| 25 | * decoder will require the custom classes) -- see {@link CustomSerializer}. |
| 26 | * <p> |
| 27 | * Default supported types are: |
| 28 | * <ul> |
| 29 | * <li>NULL (as a null value)</li> |
| 30 | * <li>String</li> |
| 31 | * <li>Boolean</li> |
| 32 | * <li>Byte</li> |
| 33 | * <li>Character</li> |
| 34 | * <li>Short</li> |
| 35 | * <li>Long</li> |
| 36 | * <li>Float</li> |
| 37 | * <li>Double</li> |
| 38 | * <li>Integer</li> |
| 39 | * <li>Enum (any enum whose name and value is known by the caller)</li> |
| 40 | * <li>java.awt.image.BufferedImage (as a {@link CustomSerializer})</li> |
| 41 | * <li>An array of the above (as a {@link CustomSerializer})</li> |
| 42 | * <li>URL</li> |
| 43 | * </ul> |
| 44 | * |
| 45 | * @author niki |
| 46 | */ |
| 47 | public class SerialUtils { |
| 48 | private static Map<String, CustomSerializer> customTypes; |
| 49 | |
| 50 | static { |
| 51 | customTypes = new HashMap<String, CustomSerializer>(); |
| 52 | |
| 53 | // Array types: |
| 54 | customTypes.put("[]", new CustomSerializer() { |
| 55 | @Override |
| 56 | protected String toString(Object value) { |
| 57 | String type = value.getClass().getCanonicalName(); |
| 58 | type = type.substring(0, type.length() - 2); // remove the [] |
| 59 | |
| 60 | StringBuilder builder = new StringBuilder(); |
| 61 | builder.append(type).append("\n"); |
| 62 | try { |
| 63 | for (int i = 0; true; i++) { |
| 64 | Object item = Array.get(value, i); |
| 65 | // encode it normally if direct value |
| 66 | if (!SerialUtils.encode(builder, item)) { |
| 67 | try { |
| 68 | // use ZIP: if not |
| 69 | builder.append(new Exporter().append(item) |
| 70 | .toString(true)); |
| 71 | } catch (NotSerializableException e) { |
| 72 | throw new UnknownFormatConversionException(e |
| 73 | .getMessage()); |
| 74 | } |
| 75 | } |
| 76 | builder.append("\n"); |
| 77 | } |
| 78 | } catch (ArrayIndexOutOfBoundsException e) { |
| 79 | // Done. |
| 80 | } |
| 81 | |
| 82 | return builder.toString(); |
| 83 | } |
| 84 | |
| 85 | @Override |
| 86 | protected String getType() { |
| 87 | return "[]"; |
| 88 | } |
| 89 | |
| 90 | @Override |
| 91 | protected Object fromString(String content) throws IOException { |
| 92 | String[] tab = content.split("\n"); |
| 93 | |
| 94 | try { |
| 95 | Object array = Array.newInstance( |
| 96 | SerialUtils.getClass(tab[0]), tab.length - 1); |
| 97 | for (int i = 1; i < tab.length; i++) { |
| 98 | Object value = new Importer().read(tab[i]).getValue(); |
| 99 | Array.set(array, i - 1, value); |
| 100 | } |
| 101 | |
| 102 | return array; |
| 103 | } catch (Exception e) { |
| 104 | if (e instanceof IOException) { |
| 105 | throw (IOException) e; |
| 106 | } |
| 107 | throw new IOException(e.getMessage()); |
| 108 | } |
| 109 | } |
| 110 | }); |
| 111 | |
| 112 | // URL: |
| 113 | customTypes.put("java.net.URL", new CustomSerializer() { |
| 114 | @Override |
| 115 | protected String toString(Object value) { |
| 116 | if (value != null) { |
| 117 | return ((URL) value).toString(); |
| 118 | } |
| 119 | return null; |
| 120 | } |
| 121 | |
| 122 | @Override |
| 123 | protected Object fromString(String content) throws IOException { |
| 124 | if (content != null) { |
| 125 | return new URL(content); |
| 126 | } |
| 127 | return null; |
| 128 | } |
| 129 | |
| 130 | @Override |
| 131 | protected String getType() { |
| 132 | return "java.net.URL"; |
| 133 | } |
| 134 | }); |
| 135 | |
| 136 | // Images (this is currently the only supported image type by default) |
| 137 | customTypes.put("be.nikiroo.utils.Image", new CustomSerializer() { |
| 138 | @Override |
| 139 | protected String toString(Object value) { |
| 140 | return ((Image) value).toBase64(); |
| 141 | } |
| 142 | |
| 143 | @Override |
| 144 | protected String getType() { |
| 145 | return "be.nikiroo.utils.Image"; |
| 146 | } |
| 147 | |
| 148 | @Override |
| 149 | protected Object fromString(String content) { |
| 150 | try { |
| 151 | return new Image(content); |
| 152 | } catch (IOException e) { |
| 153 | throw new UnknownFormatConversionException(e.getMessage()); |
| 154 | } |
| 155 | } |
| 156 | }); |
| 157 | } |
| 158 | |
| 159 | /** |
| 160 | * Create an empty object of the given type. |
| 161 | * |
| 162 | * @param type |
| 163 | * the object type (its class name) |
| 164 | * |
| 165 | * @return the new object |
| 166 | * |
| 167 | * @throws ClassNotFoundException |
| 168 | * if the class cannot be found |
| 169 | * @throws NoSuchMethodException |
| 170 | * if the given class is not compatible with this code |
| 171 | */ |
| 172 | public static Object createObject(String type) |
| 173 | throws ClassNotFoundException, NoSuchMethodException { |
| 174 | |
| 175 | String desc = null; |
| 176 | |
| 177 | try { |
| 178 | Class<?> clazz = getClass(type); |
| 179 | String className = clazz.getName(); |
| 180 | List<Object> args = new ArrayList<Object>(); |
| 181 | List<Class<?>> classes = new ArrayList<Class<?>>(); |
| 182 | Constructor<?> ctor = null; |
| 183 | if (className.contains("$")) { |
| 184 | for (String parentName = className.substring(0, |
| 185 | className.lastIndexOf('$'));; parentName = parentName |
| 186 | .substring(0, parentName.lastIndexOf('$'))) { |
| 187 | Object parent = createObject(parentName); |
| 188 | args.add(parent); |
| 189 | classes.add(parent.getClass()); |
| 190 | |
| 191 | if (!parentName.contains("$")) { |
| 192 | break; |
| 193 | } |
| 194 | } |
| 195 | |
| 196 | // Better error description in case there is no empty |
| 197 | // constructor: |
| 198 | desc = ""; |
| 199 | String end = ""; |
| 200 | for (Class<?> parent = clazz; parent != null |
| 201 | && !parent.equals(Object.class); parent = parent |
| 202 | .getSuperclass()) { |
| 203 | if (!desc.isEmpty()) { |
| 204 | desc += " [:"; |
| 205 | end += "]"; |
| 206 | } |
| 207 | desc += parent; |
| 208 | } |
| 209 | desc += end; |
| 210 | // |
| 211 | |
| 212 | ctor = clazz.getDeclaredConstructor( |
| 213 | classes.toArray(new Class[] {})); |
| 214 | desc = null; |
| 215 | } else { |
| 216 | ctor = clazz.getDeclaredConstructor(); |
| 217 | } |
| 218 | |
| 219 | ctor.setAccessible(true); |
| 220 | return ctor.newInstance(args.toArray()); |
| 221 | } catch (ClassNotFoundException e) { |
| 222 | throw e; |
| 223 | } catch (NoSuchMethodException e) { |
| 224 | if (desc != null) { |
| 225 | throw new NoSuchMethodException( |
| 226 | "Empty constructor not found: " + desc); |
| 227 | } |
| 228 | throw e; |
| 229 | } catch (Exception e) { |
| 230 | throw new NoSuchMethodException("Cannot instantiate: " + type); |
| 231 | } |
| 232 | } |
| 233 | |
| 234 | /** |
| 235 | * Insert a custom serialiser that will take precedence over the default one |
| 236 | * or the target class. |
| 237 | * |
| 238 | * @param serializer |
| 239 | * the custom serialiser |
| 240 | */ |
| 241 | static public void addCustomSerializer(CustomSerializer serializer) { |
| 242 | customTypes.put(serializer.getType(), serializer); |
| 243 | } |
| 244 | |
| 245 | /** |
| 246 | * Serialise the given object into this {@link StringBuilder}. |
| 247 | * <p> |
| 248 | * <b>Important: </b>If the operation fails (with a |
| 249 | * {@link NotSerializableException}), the {@link StringBuilder} will be |
| 250 | * corrupted (will contain bad, most probably not importable data). |
| 251 | * |
| 252 | * @param builder |
| 253 | * the output {@link StringBuilder} to serialise to |
| 254 | * @param o |
| 255 | * the object to serialise |
| 256 | * @param map |
| 257 | * the map of already serialised objects (if the given object or |
| 258 | * one of its descendant is already present in it, only an ID |
| 259 | * will be serialised) |
| 260 | * |
| 261 | * @throws NotSerializableException |
| 262 | * if the object cannot be serialised (in this case, the |
| 263 | * {@link StringBuilder} can contain bad, most probably not |
| 264 | * importable data) |
| 265 | */ |
| 266 | static void append(StringBuilder builder, Object o, Map<Integer, Object> map) |
| 267 | throws NotSerializableException { |
| 268 | |
| 269 | Field[] fields = new Field[] {}; |
| 270 | String type = ""; |
| 271 | String id = "NULL"; |
| 272 | |
| 273 | if (o != null) { |
| 274 | int hash = System.identityHashCode(o); |
| 275 | fields = o.getClass().getDeclaredFields(); |
| 276 | type = o.getClass().getCanonicalName(); |
| 277 | if (type == null) { |
| 278 | // Anonymous inner classes support |
| 279 | type = o.getClass().getName(); |
| 280 | } |
| 281 | id = Integer.toString(hash); |
| 282 | if (map.containsKey(hash)) { |
| 283 | fields = new Field[] {}; |
| 284 | } else { |
| 285 | map.put(hash, o); |
| 286 | } |
| 287 | } |
| 288 | |
| 289 | builder.append("{\nREF ").append(type).append("@").append(id) |
| 290 | .append(":"); |
| 291 | if (!encode(builder, o)) { // check if direct value |
| 292 | try { |
| 293 | for (Field field : fields) { |
| 294 | field.setAccessible(true); |
| 295 | |
| 296 | if (field.getName().startsWith("this$") |
| 297 | || field.isSynthetic() |
| 298 | || (field.getModifiers() & Modifier.STATIC) == Modifier.STATIC) { |
| 299 | // Do not keep this links of nested classes |
| 300 | // Do not keep synthetic fields |
| 301 | // Do not keep final fields |
| 302 | continue; |
| 303 | } |
| 304 | |
| 305 | builder.append("\n"); |
| 306 | builder.append(field.getName()); |
| 307 | builder.append(":"); |
| 308 | Object value; |
| 309 | |
| 310 | value = field.get(o); |
| 311 | |
| 312 | if (!encode(builder, value)) { |
| 313 | builder.append("\n"); |
| 314 | append(builder, value, map); |
| 315 | } |
| 316 | } |
| 317 | } catch (IllegalArgumentException e) { |
| 318 | e.printStackTrace(); // should not happen (see |
| 319 | // setAccessible) |
| 320 | } catch (IllegalAccessException e) { |
| 321 | e.printStackTrace(); // should not happen (see |
| 322 | // setAccessible) |
| 323 | } |
| 324 | } |
| 325 | builder.append("\n}"); |
| 326 | } |
| 327 | |
| 328 | /** |
| 329 | * Encode the object into the given builder if possible (if supported). |
| 330 | * |
| 331 | * @param builder |
| 332 | * the builder to append to |
| 333 | * @param value |
| 334 | * the object to encode (can be NULL, which will be encoded) |
| 335 | * |
| 336 | * @return TRUE if success, FALSE if not (the content of the builder won't |
| 337 | * be changed in case of failure) |
| 338 | */ |
| 339 | static boolean encode(StringBuilder builder, Object value) { |
| 340 | if (value == null) { |
| 341 | builder.append("NULL"); |
| 342 | } else if (value.getClass().getSimpleName().endsWith("[]")) { |
| 343 | // Simple name does support [] suffix and do not return NULL for |
| 344 | // inner anonymous classes |
| 345 | return customTypes.get("[]").encode(builder, value); |
| 346 | } else if (customTypes.containsKey(value.getClass().getCanonicalName())) { |
| 347 | return customTypes.get(value.getClass().getCanonicalName())// |
| 348 | .encode(builder, value); |
| 349 | } else if (value instanceof String) { |
| 350 | encodeString(builder, (String) value); |
| 351 | } else if (value instanceof Boolean) { |
| 352 | builder.append(value); |
| 353 | } else if (value instanceof Byte) { |
| 354 | builder.append(value).append('b'); |
| 355 | } else if (value instanceof Character) { |
| 356 | encodeString(builder, "" + value); |
| 357 | builder.append('c'); |
| 358 | } else if (value instanceof Short) { |
| 359 | builder.append(value).append('s'); |
| 360 | } else if (value instanceof Integer) { |
| 361 | builder.append(value); |
| 362 | } else if (value instanceof Long) { |
| 363 | builder.append(value).append('L'); |
| 364 | } else if (value instanceof Float) { |
| 365 | builder.append(value).append('F'); |
| 366 | } else if (value instanceof Double) { |
| 367 | builder.append(value).append('d'); |
| 368 | } else if (value instanceof Enum) { |
| 369 | String type = value.getClass().getCanonicalName(); |
| 370 | builder.append(type).append(".").append(((Enum<?>) value).name()) |
| 371 | .append(";"); |
| 372 | } else { |
| 373 | return false; |
| 374 | } |
| 375 | |
| 376 | return true; |
| 377 | } |
| 378 | |
| 379 | /** |
| 380 | * Decode the data into an equivalent source object. |
| 381 | * |
| 382 | * @param encodedValue |
| 383 | * the encoded data, cannot be NULL |
| 384 | * |
| 385 | * @return the object (can be NULL for NULL encoded values) |
| 386 | * |
| 387 | * @throws IOException |
| 388 | * if the content cannot be converted |
| 389 | */ |
| 390 | static Object decode(String encodedValue) throws IOException { |
| 391 | try { |
| 392 | String cut = ""; |
| 393 | if (encodedValue.length() > 1) { |
| 394 | cut = encodedValue.substring(0, encodedValue.length() - 1); |
| 395 | } |
| 396 | |
| 397 | if (CustomSerializer.isCustom(encodedValue)) { |
| 398 | // custom:TYPE_NAME:"content is String-encoded" |
| 399 | String type = CustomSerializer.typeOf(encodedValue); |
| 400 | if (customTypes.containsKey(type)) { |
| 401 | return customTypes.get(type).decode(encodedValue); |
| 402 | } |
| 403 | throw new IOException("Unknown custom type: " + type); |
| 404 | } else if (encodedValue.equals("NULL") |
| 405 | || encodedValue.equals("null")) { |
| 406 | return null; |
| 407 | } else if (encodedValue.endsWith("\"")) { |
| 408 | return decodeString(encodedValue); |
| 409 | } else if (encodedValue.equals("true")) { |
| 410 | return true; |
| 411 | } else if (encodedValue.equals("false")) { |
| 412 | return false; |
| 413 | } else if (encodedValue.endsWith("b")) { |
| 414 | return Byte.parseByte(cut); |
| 415 | } else if (encodedValue.endsWith("c")) { |
| 416 | return decodeString(cut).charAt(0); |
| 417 | } else if (encodedValue.endsWith("s")) { |
| 418 | return Short.parseShort(cut); |
| 419 | } else if (encodedValue.endsWith("L")) { |
| 420 | return Long.parseLong(cut); |
| 421 | } else if (encodedValue.endsWith("F")) { |
| 422 | return Float.parseFloat(cut); |
| 423 | } else if (encodedValue.endsWith("d")) { |
| 424 | return Double.parseDouble(cut); |
| 425 | } else if (encodedValue.endsWith(";")) { |
| 426 | return decodeEnum(encodedValue); |
| 427 | } else { |
| 428 | return Integer.parseInt(encodedValue); |
| 429 | } |
| 430 | } catch (Exception e) { |
| 431 | if (e instanceof IOException) { |
| 432 | throw (IOException) e; |
| 433 | } |
| 434 | throw new IOException(e.getMessage()); |
| 435 | } |
| 436 | } |
| 437 | |
| 438 | /** |
| 439 | * Return the corresponding class or throw an {@link Exception} if it |
| 440 | * cannot. |
| 441 | * |
| 442 | * @param type |
| 443 | * the class name to look for |
| 444 | * |
| 445 | * @return the class (will never be NULL) |
| 446 | * |
| 447 | * @throws ClassNotFoundException |
| 448 | * if the class cannot be found |
| 449 | * @throws NoSuchMethodException |
| 450 | * if the class cannot be created (usually because it or its |
| 451 | * enclosing class doesn't have an empty constructor) |
| 452 | */ |
| 453 | static private Class<?> getClass(String type) |
| 454 | throws ClassNotFoundException, NoSuchMethodException { |
| 455 | Class<?> clazz = null; |
| 456 | try { |
| 457 | clazz = Class.forName(type); |
| 458 | } catch (ClassNotFoundException e) { |
| 459 | int pos = type.length(); |
| 460 | pos = type.lastIndexOf(".", pos); |
| 461 | if (pos >= 0) { |
| 462 | String parentType = type.substring(0, pos); |
| 463 | String nestedType = type.substring(pos + 1); |
| 464 | Class<?> javaParent = null; |
| 465 | try { |
| 466 | javaParent = getClass(parentType); |
| 467 | parentType = javaParent.getName(); |
| 468 | clazz = Class.forName(parentType + "$" + nestedType); |
| 469 | } catch (Exception ee) { |
| 470 | } |
| 471 | |
| 472 | if (javaParent == null) { |
| 473 | throw new NoSuchMethodException( |
| 474 | "Class not found: " |
| 475 | + type |
| 476 | + " (the enclosing class cannot be created: maybe it doesn't have an empty constructor?)"); |
| 477 | } |
| 478 | } |
| 479 | } |
| 480 | |
| 481 | if (clazz == null) { |
| 482 | throw new ClassNotFoundException("Class not found: " + type); |
| 483 | } |
| 484 | |
| 485 | return clazz; |
| 486 | } |
| 487 | |
| 488 | @SuppressWarnings({ "unchecked", "rawtypes" }) |
| 489 | private static Enum<?> decodeEnum(String escaped) { |
| 490 | // escaped: be.xxx.EnumType.VALUE; |
| 491 | int pos = escaped.lastIndexOf("."); |
| 492 | String type = escaped.substring(0, pos); |
| 493 | String name = escaped.substring(pos + 1, escaped.length() - 1); |
| 494 | |
| 495 | try { |
| 496 | return Enum.valueOf((Class<Enum>) getClass(type), name); |
| 497 | } catch (Exception e) { |
| 498 | throw new UnknownFormatConversionException("Unknown enum: <" + type |
| 499 | + "> " + name); |
| 500 | } |
| 501 | } |
| 502 | |
| 503 | // aa bb -> "aa\tbb" |
| 504 | private static void encodeString(StringBuilder builder, String raw) { |
| 505 | builder.append('\"'); |
| 506 | for (char car : raw.toCharArray()) { |
| 507 | switch (car) { |
| 508 | case '\\': |
| 509 | builder.append("\\\\"); |
| 510 | break; |
| 511 | case '\r': |
| 512 | builder.append("\\r"); |
| 513 | break; |
| 514 | case '\n': |
| 515 | builder.append("\\n"); |
| 516 | break; |
| 517 | case '"': |
| 518 | builder.append("\\\""); |
| 519 | break; |
| 520 | default: |
| 521 | builder.append(car); |
| 522 | break; |
| 523 | } |
| 524 | } |
| 525 | builder.append('\"'); |
| 526 | } |
| 527 | |
| 528 | // "aa\tbb" -> aa bb |
| 529 | private static String decodeString(String escaped) { |
| 530 | StringBuilder builder = new StringBuilder(); |
| 531 | |
| 532 | boolean escaping = false; |
| 533 | for (char car : escaped.toCharArray()) { |
| 534 | if (!escaping) { |
| 535 | if (car == '\\') { |
| 536 | escaping = true; |
| 537 | } else { |
| 538 | builder.append(car); |
| 539 | } |
| 540 | } else { |
| 541 | switch (car) { |
| 542 | case '\\': |
| 543 | builder.append('\\'); |
| 544 | break; |
| 545 | case 'r': |
| 546 | builder.append('\r'); |
| 547 | break; |
| 548 | case 'n': |
| 549 | builder.append('\n'); |
| 550 | break; |
| 551 | case '"': |
| 552 | builder.append('"'); |
| 553 | break; |
| 554 | } |
| 555 | escaping = false; |
| 556 | } |
| 557 | } |
| 558 | |
| 559 | return builder.substring(1, builder.length() - 1); |
| 560 | } |
| 561 | } |