J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2003-2006 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package javax.sql.rowset.serial; |
| 27 | |
| 28 | import java.sql.*; |
| 29 | import javax.sql.*; |
| 30 | import java.io.*; |
| 31 | import java.math.*; |
| 32 | import java.util.Map; |
| 33 | |
| 34 | /** |
| 35 | * An input stream used for custom mapping user-defined types (UDTs). |
| 36 | * An <code>SQLInputImpl</code> object is an input stream that contains a |
| 37 | * stream of values that are the attributes of a UDT. |
| 38 | * <p> |
| 39 | * This class is used by the driver behind the scenes when the method |
| 40 | * <code>getObject</code> is called on an SQL structured or distinct type |
| 41 | * that has a custom mapping; a programmer never invokes |
| 42 | * <code>SQLInputImpl</code> methods directly. They are provided here as a |
| 43 | * convenience for those who write <code>RowSet</code> implementations. |
| 44 | * <P> |
| 45 | * The <code>SQLInputImpl</code> class provides a set of |
| 46 | * reader methods analogous to the <code>ResultSet</code> getter |
| 47 | * methods. These methods make it possible to read the values in an |
| 48 | * <code>SQLInputImpl</code> object. |
| 49 | * <P> |
| 50 | * The method <code>wasNull</code> is used to determine whether the |
| 51 | * the last value read was SQL <code>NULL</code>. |
| 52 | * <P>When the method <code>getObject</code> is called with an |
| 53 | * object of a class implementing the interface <code>SQLData</code>, |
| 54 | * the JDBC driver calls the method <code>SQLData.getSQLType</code> |
| 55 | * to determine the SQL type of the UDT being custom mapped. The driver |
| 56 | * creates an instance of <code>SQLInputImpl</code>, populating it with the |
| 57 | * attributes of the UDT. The driver then passes the input |
| 58 | * stream to the method <code>SQLData.readSQL</code>, which in turn |
| 59 | * calls the <code>SQLInputImpl</code> reader methods |
| 60 | * to read the attributes from the input stream. |
| 61 | * @see java.sql.SQLData |
| 62 | */ |
| 63 | public class SQLInputImpl implements SQLInput { |
| 64 | |
| 65 | /** |
| 66 | * <code>true</code> if the last value returned was <code>SQL NULL</code>; |
| 67 | * <code>false</code> otherwise. |
| 68 | */ |
| 69 | private boolean lastValueWasNull; |
| 70 | |
| 71 | /** |
| 72 | * The current index into the array of SQL structured type attributes |
| 73 | * that will be read from this <code>SQLInputImpl</code> object and |
| 74 | * mapped to the fields of a class in the Java programming language. |
| 75 | */ |
| 76 | private int idx; |
| 77 | |
| 78 | /** |
| 79 | * The array of attributes to be read from this stream. The order |
| 80 | * of the attributes is the same as the order in which they were |
| 81 | * listed in the SQL definition of the UDT. |
| 82 | */ |
| 83 | private Object attrib[]; |
| 84 | |
| 85 | /** |
| 86 | * The type map to use when the method <code>readObject</code> |
| 87 | * is invoked. This is a <code>java.util.Map</code> object in which |
| 88 | * there may be zero or more entries. Each entry consists of the |
| 89 | * fully qualified name of a UDT (the value to be mapped) and the |
| 90 | * <code>Class</code> object for a class that implements |
| 91 | * <code>SQLData</code> (the Java class that defines how the UDT |
| 92 | * will be mapped). |
| 93 | */ |
| 94 | private Map map; |
| 95 | |
| 96 | |
| 97 | /** |
| 98 | * Creates an <code>SQLInputImpl</code> object initialized with the |
| 99 | * given array of attributes and the given type map. If any of the |
| 100 | * attributes is a UDT whose name is in an entry in the type map, |
| 101 | * the attribute will be mapped according to the corresponding |
| 102 | * <code>SQLData</code> implementation. |
| 103 | * |
| 104 | * @param attributes an array of <code>Object</code> instances in which |
| 105 | * each element is an attribute of a UDT. The order of the |
| 106 | * attributes in the array is the same order in which |
| 107 | * the attributes were defined in the UDT definition. |
| 108 | * @param map a <code>java.util.Map</code> object containing zero or more |
| 109 | * entries, with each entry consisting of 1) a <code>String</code> |
| 110 | * giving the fully |
| 111 | * qualified name of the UDT and 2) the <code>Class</code> object |
| 112 | * for the <code>SQLData</code> implementation that defines how |
| 113 | * the UDT is to be mapped |
| 114 | * @throws SQLException if the <code>attributes</code> or the <code>map</code> |
| 115 | * is a <code>null</code> value |
| 116 | */ |
| 117 | |
| 118 | public SQLInputImpl(Object[] attributes, Map<String,Class<?>> map) |
| 119 | throws SQLException |
| 120 | { |
| 121 | if ((attributes == null) || (map == null)) { |
| 122 | throw new SQLException("Cannot instantiate a SQLInputImpl " + |
| 123 | "object with null parameters"); |
| 124 | } |
| 125 | // assign our local reference to the attribute stream |
| 126 | attrib = attributes; |
| 127 | // init the index point before the head of the stream |
| 128 | idx = -1; |
| 129 | // set the map |
| 130 | this.map = map; |
| 131 | } |
| 132 | |
| 133 | |
| 134 | /** |
| 135 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object |
| 136 | * as an <code>Object</code> in the Java programming language. |
| 137 | * |
| 138 | * @return the next value in the input stream |
| 139 | * as an <code>Object</code> in the Java programming language |
| 140 | * @throws SQLException if the read position is located at an invalid |
| 141 | * position or if there are no further values in the stream |
| 142 | */ |
| 143 | private Object getNextAttribute() throws SQLException { |
| 144 | if (++idx >= attrib.length) { |
| 145 | throw new SQLException("SQLInputImpl exception: Invalid read " + |
| 146 | "position"); |
| 147 | } else { |
| 148 | return attrib[idx]; |
| 149 | } |
| 150 | } |
| 151 | |
| 152 | |
| 153 | //================================================================ |
| 154 | // Methods for reading attributes from the stream of SQL data. |
| 155 | // These methods correspond to the column-accessor methods of |
| 156 | // java.sql.ResultSet. |
| 157 | //================================================================ |
| 158 | |
| 159 | /** |
| 160 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object as |
| 161 | * a <code>String</code> in the Java programming language. |
| 162 | * <p> |
| 163 | * This method does not perform type-safe checking to determine if the |
| 164 | * returned type is the expected type; this responsibility is delegated |
| 165 | * to the UDT mapping as defined by a <code>SQLData</code> |
| 166 | * implementation. |
| 167 | * <p> |
| 168 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 169 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 170 | * @throws SQLException if the read position is located at an invalid |
| 171 | * position or if there are no further values in the stream. |
| 172 | */ |
| 173 | public String readString() throws SQLException { |
| 174 | |
| 175 | String attrib = (String)getNextAttribute(); |
| 176 | |
| 177 | if (attrib == null) { |
| 178 | lastValueWasNull = true; |
| 179 | return null; |
| 180 | } else { |
| 181 | lastValueWasNull = false; |
| 182 | return attrib; |
| 183 | } |
| 184 | } |
| 185 | |
| 186 | /** |
| 187 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object as |
| 188 | * a <code>boolean</code> in the Java programming language. |
| 189 | * <p> |
| 190 | * This method does not perform type-safe checking to determine if the |
| 191 | * returned type is the expected type; this responsibility is delegated |
| 192 | * to the UDT mapping as defined by a <code>SQLData</code> |
| 193 | * implementation. |
| 194 | * <p> |
| 195 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 196 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 197 | * @throws SQLException if the read position is located at an invalid |
| 198 | * position or if there are no further values in the stream. |
| 199 | */ |
| 200 | public boolean readBoolean() throws SQLException { |
| 201 | |
| 202 | Boolean attrib = (Boolean)getNextAttribute(); |
| 203 | |
| 204 | if (attrib == null) { |
| 205 | lastValueWasNull = true; |
| 206 | return false; |
| 207 | } else { |
| 208 | lastValueWasNull = false; |
| 209 | return attrib.booleanValue(); |
| 210 | } |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object as |
| 215 | * a <code>byte</code> in the Java programming language. |
| 216 | * <p> |
| 217 | * This method does not perform type-safe checking to determine if the |
| 218 | * returned type is the expected type; this responsibility is delegated |
| 219 | * to the UDT mapping as defined by a <code>SQLData</code> |
| 220 | * implementation. |
| 221 | * <p> |
| 222 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 223 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 224 | * @throws SQLException if the read position is located at an invalid |
| 225 | * position or if there are no further values in the stream |
| 226 | */ |
| 227 | public byte readByte() throws SQLException { |
| 228 | Byte attrib = (Byte)getNextAttribute(); |
| 229 | |
| 230 | if (attrib == null) { |
| 231 | lastValueWasNull = true; |
| 232 | return (byte)0; |
| 233 | } else { |
| 234 | lastValueWasNull = false; |
| 235 | return attrib.byteValue(); |
| 236 | } |
| 237 | } |
| 238 | |
| 239 | /** |
| 240 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object |
| 241 | * as a <code>short</code> in the Java programming language. |
| 242 | * <P> |
| 243 | * This method does not perform type-safe checking to determine if the |
| 244 | * returned type is the expected type; this responsibility is delegated |
| 245 | * to the UDT mapping as defined by a <code>SQLData</code> implementation. |
| 246 | * <P> |
| 247 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 248 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 249 | * @throws SQLException if the read position is located at an invalid |
| 250 | * position or if there are no more values in the stream |
| 251 | */ |
| 252 | public short readShort() throws SQLException { |
| 253 | Short attrib = (Short)getNextAttribute(); |
| 254 | |
| 255 | if (attrib == null) { |
| 256 | lastValueWasNull = true; |
| 257 | return (short)0; |
| 258 | } else { |
| 259 | lastValueWasNull = false; |
| 260 | return attrib.shortValue(); |
| 261 | } |
| 262 | } |
| 263 | |
| 264 | /** |
| 265 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object |
| 266 | * as an <code>int</code> in the Java programming language. |
| 267 | * <P> |
| 268 | * This method does not perform type-safe checking to determine if the |
| 269 | * returned type is the expected type; this responsibility is delegated |
| 270 | * to the UDT mapping as defined by a <code>SQLData</code> implementation. |
| 271 | * <P> |
| 272 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 273 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 274 | * @throws SQLException if the read position is located at an invalid |
| 275 | * position or if there are no more values in the stream |
| 276 | */ |
| 277 | public int readInt() throws SQLException { |
| 278 | Integer attrib = (Integer)getNextAttribute(); |
| 279 | |
| 280 | if (attrib == null) { |
| 281 | lastValueWasNull = true; |
| 282 | return (int)0; |
| 283 | } else { |
| 284 | lastValueWasNull = false; |
| 285 | return attrib.intValue(); |
| 286 | } |
| 287 | } |
| 288 | |
| 289 | /** |
| 290 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object |
| 291 | * as a <code>long</code> in the Java programming language. |
| 292 | * <P> |
| 293 | * This method does not perform type-safe checking to determine if the |
| 294 | * returned type is the expected type; this responsibility is delegated |
| 295 | * to the UDT mapping as defined by a <code>SQLData</code> implementation. |
| 296 | * <P> |
| 297 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 298 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 299 | * @throws SQLException if the read position is located at an invalid |
| 300 | * position or if there are no more values in the stream |
| 301 | */ |
| 302 | public long readLong() throws SQLException { |
| 303 | Long attrib = (Long)getNextAttribute(); |
| 304 | |
| 305 | if (attrib == null) { |
| 306 | lastValueWasNull = true; |
| 307 | return (long)0; |
| 308 | } else { |
| 309 | lastValueWasNull = false; |
| 310 | return attrib.longValue(); |
| 311 | } |
| 312 | } |
| 313 | |
| 314 | /** |
| 315 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object |
| 316 | * as a <code>float</code> in the Java programming language. |
| 317 | * <P> |
| 318 | * This method does not perform type-safe checking to determine if the |
| 319 | * returned type is the expected type; this responsibility is delegated |
| 320 | * to the UDT mapping as defined by a <code>SQLData</code> implementation. |
| 321 | * <P> |
| 322 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 323 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 324 | * @throws SQLException if the read position is located at an invalid |
| 325 | * position or if there are no more values in the stream |
| 326 | */ |
| 327 | public float readFloat() throws SQLException { |
| 328 | Float attrib = (Float)getNextAttribute(); |
| 329 | |
| 330 | if (attrib == null) { |
| 331 | lastValueWasNull = true; |
| 332 | return (float)0; |
| 333 | } else { |
| 334 | lastValueWasNull = false; |
| 335 | return attrib.floatValue(); |
| 336 | } |
| 337 | } |
| 338 | |
| 339 | /** |
| 340 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object |
| 341 | * as a <code>double</code> in the Java programming language. |
| 342 | * <P> |
| 343 | * This method does not perform type-safe checking to determine if the |
| 344 | * returned type is the expected type; this responsibility is delegated |
| 345 | * to the UDT mapping as defined by a <code>SQLData</code> implementation. |
| 346 | * <P> |
| 347 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 348 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 349 | * @throws SQLException if the read position is located at an invalid |
| 350 | * position or if there are no more values in the stream |
| 351 | */ |
| 352 | public double readDouble() throws SQLException { |
| 353 | Double attrib = (Double)getNextAttribute(); |
| 354 | |
| 355 | if (attrib == null) { |
| 356 | lastValueWasNull = true; |
| 357 | return (double)0; |
| 358 | } else { |
| 359 | lastValueWasNull = false; |
| 360 | return attrib.doubleValue(); |
| 361 | } |
| 362 | } |
| 363 | |
| 364 | /** |
| 365 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object |
| 366 | * as a <code>java.math.BigDecimal</code>. |
| 367 | * <P> |
| 368 | * This method does not perform type-safe checking to determine if the |
| 369 | * returned type is the expected type; this responsibility is delegated |
| 370 | * to the UDT mapping as defined by a <code>SQLData</code> implementation. |
| 371 | * <P> |
| 372 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 373 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 374 | * @throws SQLException if the read position is located at an invalid |
| 375 | * position or if there are no more values in the stream |
| 376 | */ |
| 377 | public java.math.BigDecimal readBigDecimal() throws SQLException { |
| 378 | java.math.BigDecimal attrib = (java.math.BigDecimal)getNextAttribute(); |
| 379 | |
| 380 | if (attrib == null) { |
| 381 | lastValueWasNull = true; |
| 382 | return null; |
| 383 | } else { |
| 384 | lastValueWasNull = false; |
| 385 | return attrib; |
| 386 | } |
| 387 | } |
| 388 | |
| 389 | /** |
| 390 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object |
| 391 | * as an array of bytes. |
| 392 | * <p> |
| 393 | * This method does not perform type-safe checking to determine if the |
| 394 | * returned type is the expected type; this responsibility is delegated |
| 395 | * to the UDT mapping as defined by a <code>SQLData</code> implementation. |
| 396 | * <P> |
| 397 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 398 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 399 | * @throws SQLException if the read position is located at an invalid |
| 400 | * position or if there are no more values in the stream |
| 401 | */ |
| 402 | public byte[] readBytes() throws SQLException { |
| 403 | byte[] attrib = (byte[])getNextAttribute(); |
| 404 | |
| 405 | if (attrib == null) { |
| 406 | lastValueWasNull = true; |
| 407 | return null; |
| 408 | } else { |
| 409 | lastValueWasNull = false; |
| 410 | return attrib; |
| 411 | } |
| 412 | } |
| 413 | |
| 414 | /** |
| 415 | * Retrieves the next attribute in this <code>SQLInputImpl</code> as |
| 416 | * a <code>java.sql.Date</code> object. |
| 417 | * <P> |
| 418 | * This method does not perform type-safe checking to determine if the |
| 419 | * returned type is the expected type; this responsibility is delegated |
| 420 | * to the UDT mapping as defined by a <code>SQLData</code> implementation. |
| 421 | * <P> |
| 422 | * @return the next attribute in this <code>SQLInputImpl</code> object; |
| 423 | * if the value is <code>SQL NULL</code>, return <code>null</code> |
| 424 | * @throws SQLException if the read position is located at an invalid |
| 425 | * position or if there are no more values in the stream |
| 426 | */ |
| 427 | public java.sql.Date readDate() throws SQLException { |
| 428 | java.sql.Date attrib = (java.sql.Date)getNextAttribute(); |
| 429 | |
| 430 | if (attrib == null) { |
| 431 | lastValueWasNull = true; |
| 432 | return null; |
| 433 | } else { |
| 434 | lastValueWasNull = false; |
| 435 | return attrib; |
| 436 | } |
| 437 | } |
| 438 | |
| 439 | /** |
| 440 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object as |
| 441 | * a <code>java.sql.Time</code> object. |
| 442 | * <P> |
| 443 | * This method does not perform type-safe checking to determine if the |
| 444 | * returned type is the expected type as this responsibility is delegated |
| 445 | * to the UDT mapping as implemented by a <code>SQLData</code> |
| 446 | * implementation. |
| 447 | * |
| 448 | * @return the attribute; if the value is <code>SQL NULL</code>, return |
| 449 | * <code>null</code> |
| 450 | * @throws SQLException if the read position is located at an invalid |
| 451 | * position; or if there are no further values in the stream. |
| 452 | */ |
| 453 | public java.sql.Time readTime() throws SQLException { |
| 454 | java.sql.Time attrib = (java.sql.Time)getNextAttribute(); |
| 455 | |
| 456 | if (attrib == null) { |
| 457 | lastValueWasNull = true; |
| 458 | return null; |
| 459 | } else { |
| 460 | lastValueWasNull = false; |
| 461 | return attrib; |
| 462 | } |
| 463 | } |
| 464 | |
| 465 | /** |
| 466 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object as |
| 467 | * a <code>java.sql.Timestamp</code> object. |
| 468 | * |
| 469 | * @return the attribute; if the value is <code>SQL NULL</code>, return |
| 470 | * <code>null</code> |
| 471 | * @throws SQLException if the read position is located at an invalid |
| 472 | * position; or if there are no further values in the stream. |
| 473 | */ |
| 474 | public java.sql.Timestamp readTimestamp() throws SQLException { |
| 475 | java.sql.Timestamp attrib = (java.sql.Timestamp)getNextAttribute(); |
| 476 | |
| 477 | if (attrib == null) { |
| 478 | lastValueWasNull = true; |
| 479 | return null; |
| 480 | } else { |
| 481 | lastValueWasNull = false; |
| 482 | return attrib; |
| 483 | } |
| 484 | } |
| 485 | |
| 486 | /** |
| 487 | * Retrieves the next attribute in this <code>SQLInputImpl</code> object |
| 488 | * as a stream of Unicode characters. |
| 489 | * <P> |
| 490 | * This method does not perform type-safe checking to determine if the |
| 491 | * returned type is the expected type as this responsibility is delegated |
| 492 | * to the UDT mapping as implemented by a <code>SQLData</code> |
| 493 | * implementation. |
| 494 | * |
| 495 | * @return the attribute; if the value is <code>SQL NULL</code>, return <code>null</code> |
| 496 | * @throws SQLException if the read position is located at an invalid |
| 497 | * position; or if there are no further values in the stream. |
| 498 | */ |
| 499 | public java.io.Reader readCharacterStream() throws SQLException { |
| 500 | java.io.Reader attrib = (java.io.Reader)getNextAttribute(); |
| 501 | |
| 502 | if (attrib == null) { |
| 503 | lastValueWasNull = true; |
| 504 | return null; |
| 505 | } else { |
| 506 | lastValueWasNull = false; |
| 507 | return attrib; |
| 508 | } |
| 509 | } |
| 510 | |
| 511 | /** |
| 512 | * Returns the next attribute in this <code>SQLInputImpl</code> object |
| 513 | * as a stream of ASCII characters. |
| 514 | * <P> |
| 515 | * This method does not perform type-safe checking to determine if the |
| 516 | * returned type is the expected type as this responsibility is delegated |
| 517 | * to the UDT mapping as implemented by a <code>SQLData</code> |
| 518 | * implementation. |
| 519 | * |
| 520 | * @return the attribute; if the value is <code>SQL NULL</code>, |
| 521 | * return <code>null</code> |
| 522 | * @throws SQLException if the read position is located at an invalid |
| 523 | * position; or if there are no further values in the stream. |
| 524 | */ |
| 525 | public java.io.InputStream readAsciiStream() throws SQLException { |
| 526 | java.io.InputStream attrib = (java.io.InputStream)getNextAttribute(); |
| 527 | |
| 528 | if (attrib == null) { |
| 529 | lastValueWasNull = true; |
| 530 | return null; |
| 531 | } else { |
| 532 | lastValueWasNull = false; |
| 533 | return attrib; |
| 534 | } |
| 535 | } |
| 536 | |
| 537 | /** |
| 538 | * Returns the next attribute in this <code>SQLInputImpl</code> object |
| 539 | * as a stream of uninterpreted bytes. |
| 540 | * <P> |
| 541 | * This method does not perform type-safe checking to determine if the |
| 542 | * returned type is the expected type as this responsibility is delegated |
| 543 | * to the UDT mapping as implemented by a <code>SQLData</code> |
| 544 | * implementation. |
| 545 | * |
| 546 | * @return the attribute; if the value is <code>SQL NULL</code>, return |
| 547 | * <code>null</code> |
| 548 | * @throws SQLException if the read position is located at an invalid |
| 549 | * position; or if there are no further values in the stream. |
| 550 | */ |
| 551 | public java.io.InputStream readBinaryStream() throws SQLException { |
| 552 | java.io.InputStream attrib = (java.io.InputStream)getNextAttribute(); |
| 553 | |
| 554 | if (attrib == null) { |
| 555 | lastValueWasNull = true; |
| 556 | return null; |
| 557 | } else { |
| 558 | lastValueWasNull = false; |
| 559 | return attrib; |
| 560 | } |
| 561 | } |
| 562 | |
| 563 | //================================================================ |
| 564 | // Methods for reading items of SQL user-defined types from the stream. |
| 565 | //================================================================ |
| 566 | |
| 567 | /** |
| 568 | * Retrieves the value at the head of this <code>SQLInputImpl</code> |
| 569 | * object as an <code>Object</code> in the Java programming language. The |
| 570 | * actual type of the object returned is determined by the default |
| 571 | * mapping of SQL types to types in the Java programming language unless |
| 572 | * there is a custom mapping, in which case the type of the object |
| 573 | * returned is determined by this stream's type map. |
| 574 | * <P> |
| 575 | * The JDBC technology-enabled driver registers a type map with the stream |
| 576 | * before passing the stream to the application. |
| 577 | * <P> |
| 578 | * When the datum at the head of the stream is an SQL <code>NULL</code>, |
| 579 | * this method returns <code>null</code>. If the datum is an SQL |
| 580 | * structured or distinct type with a custom mapping, this method |
| 581 | * determines the SQL type of the datum at the head of the stream, |
| 582 | * constructs an object of the appropriate class, and calls the method |
| 583 | * <code>SQLData.readSQL</code> on that object. The <code>readSQL</code> |
| 584 | * method then calls the appropriate <code>SQLInputImpl.readXXX</code> |
| 585 | * methods to retrieve the attribute values from the stream. |
| 586 | * |
| 587 | * @return the value at the head of the stream as an <code>Object</code> |
| 588 | * in the Java programming language; <code>null</code> if |
| 589 | * the value is SQL <code>NULL</code> |
| 590 | * @throws SQLException if the read position is located at an invalid |
| 591 | * position; or if there are no further values in the stream. |
| 592 | */ |
| 593 | public Object readObject() throws SQLException { |
| 594 | Object attrib = (Object)getNextAttribute(); |
| 595 | |
| 596 | if (attrib == null) { |
| 597 | lastValueWasNull = true; |
| 598 | return null; |
| 599 | } else { |
| 600 | lastValueWasNull = false; |
| 601 | if (attrib instanceof Struct) { |
| 602 | Struct s = (Struct)attrib; |
| 603 | // look up the class in the map |
| 604 | Class c = (Class)map.get(s.getSQLTypeName()); |
| 605 | if (c != null) { |
| 606 | // create new instance of the class |
| 607 | SQLData obj = null; |
| 608 | try { |
| 609 | obj = (SQLData)c.newInstance(); |
| 610 | } catch (java.lang.InstantiationException ex) { |
| 611 | throw new SQLException("Unable to instantiate: " + |
| 612 | ex.getMessage()); |
| 613 | } catch (java.lang.IllegalAccessException ex) { |
| 614 | throw new SQLException("Unable to instantiate: " + |
| 615 | ex.getMessage()); |
| 616 | } |
| 617 | // get the attributes from the struct |
| 618 | Object attribs[] = s.getAttributes(map); |
| 619 | // create the SQLInput "stream" |
| 620 | SQLInputImpl sqlInput = new SQLInputImpl(attribs, map); |
| 621 | // read the values... |
| 622 | obj.readSQL(sqlInput, s.getSQLTypeName()); |
| 623 | return (Object)obj; |
| 624 | } |
| 625 | } |
| 626 | return (Object)attrib; |
| 627 | } |
| 628 | } |
| 629 | |
| 630 | /** |
| 631 | * Retrieves the value at the head of this <code>SQLInputImpl</code> object |
| 632 | * as a <code>Ref</code> object in the Java programming language. |
| 633 | * |
| 634 | * @return a <code>Ref</code> object representing the SQL |
| 635 | * <code>REF</code> value at the head of the stream; if the value |
| 636 | * is <code>SQL NULL</code> return <code>null</code> |
| 637 | * @throws SQLException if the read position is located at an invalid |
| 638 | * position; or if there are no further values in the stream. |
| 639 | */ |
| 640 | public Ref readRef() throws SQLException { |
| 641 | Ref attrib = (Ref)getNextAttribute(); |
| 642 | |
| 643 | if (attrib == null) { |
| 644 | lastValueWasNull = true; |
| 645 | return null; |
| 646 | } else { |
| 647 | lastValueWasNull = false; |
| 648 | return attrib; |
| 649 | } |
| 650 | } |
| 651 | |
| 652 | /** |
| 653 | * Retrieves the <code>BLOB</code> value at the head of this |
| 654 | * <code>SQLInputImpl</code> object as a <code>Blob</code> object |
| 655 | * in the Java programming language. |
| 656 | * <P> |
| 657 | * This method does not perform type-safe checking to determine if the |
| 658 | * returned type is the expected type as this responsibility is delegated |
| 659 | * to the UDT mapping as implemented by a <code>SQLData</code> |
| 660 | * implementation. |
| 661 | * |
| 662 | * @return a <code>Blob</code> object representing the SQL |
| 663 | * <code>BLOB</code> value at the head of this stream; |
| 664 | * if the value is <code>SQL NULL</code>, return |
| 665 | * <code>null</code> |
| 666 | * @throws SQLException if the read position is located at an invalid |
| 667 | * position; or if there are no further values in the stream. |
| 668 | */ |
| 669 | public Blob readBlob() throws SQLException { |
| 670 | Blob attrib = (Blob)getNextAttribute(); |
| 671 | |
| 672 | if (attrib == null) { |
| 673 | lastValueWasNull = true; |
| 674 | return null; |
| 675 | } else { |
| 676 | lastValueWasNull = false; |
| 677 | return attrib; |
| 678 | } |
| 679 | } |
| 680 | |
| 681 | /** |
| 682 | * Retrieves the <code>CLOB</code> value at the head of this |
| 683 | * <code>SQLInputImpl</code> object as a <code>Clob</code> object |
| 684 | * in the Java programming language. |
| 685 | * <P> |
| 686 | * This method does not perform type-safe checking to determine if the |
| 687 | * returned type is the expected type as this responsibility is delegated |
| 688 | * to the UDT mapping as implemented by a <code>SQLData</code> |
| 689 | * implementation. |
| 690 | * |
| 691 | * @return a <code>Clob</code> object representing the SQL |
| 692 | * <code>CLOB</code> value at the head of the stream; |
| 693 | * if the value is <code>SQL NULL</code>, return |
| 694 | * <code>null</code> |
| 695 | * @throws SQLException if the read position is located at an invalid |
| 696 | * position; or if there are no further values in the stream. |
| 697 | */ |
| 698 | public Clob readClob() throws SQLException { |
| 699 | |
| 700 | Clob attrib = (Clob)getNextAttribute(); |
| 701 | if (attrib == null) { |
| 702 | lastValueWasNull = true; |
| 703 | return null; |
| 704 | } else { |
| 705 | lastValueWasNull = false; |
| 706 | return attrib; |
| 707 | } |
| 708 | } |
| 709 | |
| 710 | /** |
| 711 | * Reads an SQL <code>ARRAY</code> value from the stream and |
| 712 | * returns it as an <code>Array</code> object in the Java programming |
| 713 | * language. |
| 714 | * <P> |
| 715 | * This method does not perform type-safe checking to determine if the |
| 716 | * returned type is the expected type as this responsibility is delegated |
| 717 | * to the UDT mapping as implemented by a <code>SQLData</code> |
| 718 | * implementation. |
| 719 | * |
| 720 | * @return an <code>Array</code> object representing the SQL |
| 721 | * <code>ARRAY</code> value at the head of the stream; * |
| 722 | * if the value is <code>SQL NULL</code>, return |
| 723 | * <code>null</code> |
| 724 | * @throws SQLException if the read position is located at an invalid |
| 725 | * position; or if there are no further values in the stream. |
| 726 | |
| 727 | */ |
| 728 | public Array readArray() throws SQLException { |
| 729 | Array attrib = (Array)getNextAttribute(); |
| 730 | |
| 731 | if (attrib == null) { |
| 732 | lastValueWasNull = true; |
| 733 | return null; |
| 734 | } else { |
| 735 | lastValueWasNull = false; |
| 736 | return attrib; |
| 737 | } |
| 738 | } |
| 739 | |
| 740 | /** |
| 741 | * Ascertains whether the last value read from this |
| 742 | * <code>SQLInputImpl</code> object was <code>null</code>. |
| 743 | * |
| 744 | * @return <code>true</code> if the SQL value read most recently was |
| 745 | * <code>null</code>; otherwise, <code>false</code>; by default it |
| 746 | * will return false |
| 747 | * @throws SQLException if an error occurs determining the last value |
| 748 | * read was a <code>null</code> value or not; |
| 749 | */ |
| 750 | public boolean wasNull() throws SQLException { |
| 751 | return lastValueWasNull; |
| 752 | } |
| 753 | |
| 754 | /** |
| 755 | * Reads an SQL <code>DATALINK</code> value from the stream and |
| 756 | * returns it as an <code>URL</code> object in the Java programming |
| 757 | * language. |
| 758 | * <P> |
| 759 | * This method does not perform type-safe checking to determine if the |
| 760 | * returned type is the expected type as this responsibility is delegated |
| 761 | * to the UDT mapping as implemented by a <code>SQLData</code> |
| 762 | * implementation. |
| 763 | * |
| 764 | * @return an <code>URL</code> object representing the SQL |
| 765 | * <code>DATALINK</code> value at the head of the stream; * |
| 766 | * if the value is <code>SQL NULL</code>, return |
| 767 | * <code>null</code> |
| 768 | * @throws SQLException if the read position is located at an invalid |
| 769 | * position; or if there are no further values in the stream. |
| 770 | */ |
| 771 | public java.net.URL readURL() throws SQLException { |
| 772 | throw new SQLException("Operation not supported"); |
| 773 | } |
| 774 | |
| 775 | //---------------------------- JDBC 4.0 ------------------------- |
| 776 | |
| 777 | /** |
| 778 | * Reads an SQL <code>NCLOB</code> value from the stream and returns it as a |
| 779 | * <code>Clob</code> object in the Java programming language. |
| 780 | * |
| 781 | * @return a <code>NClob</code> object representing data of the SQL <code>NCLOB</code> value |
| 782 | * at the head of the stream; <code>null</code> if the value read is |
| 783 | * SQL <code>NULL</code> |
| 784 | * @exception SQLException if a database access error occurs |
| 785 | */ |
| 786 | public NClob readNClob() throws SQLException { |
| 787 | throw new UnsupportedOperationException("Operation not supported"); |
| 788 | } |
| 789 | |
| 790 | /** |
| 791 | * Reads the next attribute in the stream and returns it as a <code>String</code> |
| 792 | * in the Java programming language. It is intended for use when |
| 793 | * accessing <code>NCHAR</code>,<code>NVARCHAR</code> |
| 794 | * and <code>LONGNVARCHAR</code> columns. |
| 795 | * |
| 796 | * @return the attribute; if the value is SQL <code>NULL</code>, returns <code>null</code> |
| 797 | * @exception SQLException if a database access error occurs |
| 798 | */ |
| 799 | public String readNString() throws SQLException { |
| 800 | throw new UnsupportedOperationException("Operation not supported"); |
| 801 | } |
| 802 | |
| 803 | /** |
| 804 | * Reads an SQL <code>XML</code> value from the stream and returns it as a |
| 805 | * <code>SQLXML</code> object in the Java programming language. |
| 806 | * |
| 807 | * @return a <code>SQLXML</code> object representing data of the SQL <code>XML</code> value |
| 808 | * at the head of the stream; <code>null</code> if the value read is |
| 809 | * SQL <code>NULL</code> |
| 810 | * @exception SQLException if a database access error occurs |
| 811 | */ |
| 812 | public SQLXML readSQLXML() throws SQLException { |
| 813 | throw new UnsupportedOperationException("Operation not supported"); |
| 814 | } |
| 815 | |
| 816 | /** |
| 817 | * Reads an SQL <code>ROWID</code> value from the stream and returns it as a |
| 818 | * <code>RowId</code> object in the Java programming language. |
| 819 | * |
| 820 | * @return a <code>RowId</code> object representing data of the SQL <code>ROWID</code> value |
| 821 | * at the head of the stream; <code>null</code> if the value read is |
| 822 | * SQL <code>NULL</code> |
| 823 | * @exception SQLException if a database access error occurs |
| 824 | */ |
| 825 | public RowId readRowId() throws SQLException { |
| 826 | throw new UnsupportedOperationException("Operation not supported"); |
| 827 | } |
| 828 | |
| 829 | |
| 830 | } |