001: /*
002: * Copyright 1998-2006 Sun Microsystems, Inc. All Rights Reserved.
003: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004: *
005: * This code is free software; you can redistribute it and/or modify it
006: * under the terms of the GNU General Public License version 2 only, as
007: * published by the Free Software Foundation. Sun designates this
008: * particular file as subject to the "Classpath" exception as provided
009: * by Sun in the LICENSE file that accompanied this code.
010: *
011: * This code is distributed in the hope that it will be useful, but WITHOUT
012: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
014: * version 2 for more details (a copy is included in the LICENSE file that
015: * accompanied this code).
016: *
017: * You should have received a copy of the GNU General Public License version
018: * 2 along with this work; if not, write to the Free Software Foundation,
019: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020: *
021: * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022: * CA 95054 USA or visit www.sun.com if you need additional information or
023: * have any questions.
024: */
025:
026: package java.sql;
027:
028: import java.io.InputStream;
029:
030: /**
031: * The representation (mapping) in
032: * the Java<sup><font size=-2>TM</font></sup> programming
033: * language of an SQL
034: * <code>BLOB</code> value. An SQL <code>BLOB</code> is a built-in type
035: * that stores a Binary Large Object as a column value in a row of
036: * a database table. By default drivers implement <code>Blob</code> using
037: * an SQL <code>locator(BLOB)</code>, which means that a
038: * <code>Blob</code> object contains a logical pointer to the
039: * SQL <code>BLOB</code> data rather than the data itself.
040: * A <code>Blob</code> object is valid for the duration of the
041: * transaction in which is was created.
042: *
043: * <P>Methods in the interfaces {@link ResultSet},
044: * {@link CallableStatement}, and {@link PreparedStatement}, such as
045: * <code>getBlob</code> and <code>setBlob</code> allow a programmer to
046: * access an SQL <code>BLOB</code> value.
047: * The <code>Blob</code> interface provides methods for getting the
048: * length of an SQL <code>BLOB</code> (Binary Large Object) value,
049: * for materializing a <code>BLOB</code> value on the client, and for
050: * determining the position of a pattern of bytes within a
051: * <code>BLOB</code> value. In addition, this interface has methods for updating
052: * a <code>BLOB</code> value.
053: * <p>
054: * All methods on the <code>Blob</code> interface must be fully implemented if the
055: * JDBC driver supports the data type.
056: *
057: * @since 1.2
058: */
059:
060: public interface Blob {
061:
062: /**
063: * Returns the number of bytes in the <code>BLOB</code> value
064: * designated by this <code>Blob</code> object.
065: * @return length of the <code>BLOB</code> in bytes
066: * @exception SQLException if there is an error accessing the
067: * length of the <code>BLOB</code>
068: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
069: * this method
070: * @since 1.2
071: */
072: long length() throws SQLException;
073:
074: /**
075: * Retrieves all or part of the <code>BLOB</code>
076: * value that this <code>Blob</code> object represents, as an array of
077: * bytes. This <code>byte</code> array contains up to <code>length</code>
078: * consecutive bytes starting at position <code>pos</code>.
079: *
080: * @param pos the ordinal position of the first byte in the
081: * <code>BLOB</code> value to be extracted; the first byte is at
082: * position 1
083: * @param length the number of consecutive bytes to be copied; the value
084: * for length must be 0 or greater
085: * @return a byte array containing up to <code>length</code>
086: * consecutive bytes from the <code>BLOB</code> value designated
087: * by this <code>Blob</code> object, starting with the
088: * byte at position <code>pos</code>
089: * @exception SQLException if there is an error accessing the
090: * <code>BLOB</code> value; if pos is less than 1 or length is
091: * less than 0
092: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
093: * this method
094: * @see #setBytes
095: * @since 1.2
096: */
097: byte[] getBytes(long pos, int length) throws SQLException;
098:
099: /**
100: * Retrieves the <code>BLOB</code> value designated by this
101: * <code>Blob</code> instance as a stream.
102: *
103: * @return a stream containing the <code>BLOB</code> data
104: * @exception SQLException if there is an error accessing the
105: * <code>BLOB</code> value
106: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
107: * this method
108: * @see #setBinaryStream
109: * @since 1.2
110: */
111: java.io.InputStream getBinaryStream() throws SQLException;
112:
113: /**
114: * Retrieves the byte position at which the specified byte array
115: * <code>pattern</code> begins within the <code>BLOB</code>
116: * value that this <code>Blob</code> object represents. The
117: * search for <code>pattern</code> begins at position
118: * <code>start</code>.
119: *
120: * @param pattern the byte array for which to search
121: * @param start the position at which to begin searching; the
122: * first position is 1
123: * @return the position at which the pattern appears, else -1
124: * @exception SQLException if there is an error accessing the
125: * <code>BLOB</code> or if start is less than 1
126: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
127: * this method
128: * @since 1.2
129: */
130: long position(byte pattern[], long start) throws SQLException;
131:
132: /**
133: * Retrieves the byte position in the <code>BLOB</code> value
134: * designated by this <code>Blob</code> object at which
135: * <code>pattern</code> begins. The search begins at position
136: * <code>start</code>.
137: *
138: * @param pattern the <code>Blob</code> object designating
139: * the <code>BLOB</code> value for which to search
140: * @param start the position in the <code>BLOB</code> value
141: * at which to begin searching; the first position is 1
142: * @return the position at which the pattern begins, else -1
143: * @exception SQLException if there is an error accessing the
144: * <code>BLOB</code> value or if start is less than 1
145: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
146: * this method
147: * @since 1.2
148: */
149: long position(Blob pattern, long start) throws SQLException;
150:
151: // -------------------------- JDBC 3.0 -----------------------------------
152:
153: /**
154: * Writes the given array of bytes to the <code>BLOB</code> value that
155: * this <code>Blob</code> object represents, starting at position
156: * <code>pos</code>, and returns the number of bytes written.
157: * The array of bytes will overwrite the existing bytes
158: * in the <code>Blob</code> object starting at the position
159: * <code>pos</code>. If the end of the <code>Blob</code> value is reached
160: * while writing the array of bytes, then the length of the <code>Blob</code>
161: * value will be increased to accomodate the extra bytes.
162: * <p>
163: * <b>Note:</b> If the value specified for <code>pos</code>
164: * is greater then the length+1 of the <code>BLOB</code> value then the
165: * behavior is undefined. Some JDBC drivers may throw a
166: * <code>SQLException</code> while other drivers may support this
167: * operation.
168: *
169: * @param pos the position in the <code>BLOB</code> object at which
170: * to start writing; the first position is 1
171: * @param bytes the array of bytes to be written to the <code>BLOB</code>
172: * value that this <code>Blob</code> object represents
173: * @return the number of bytes written
174: * @exception SQLException if there is an error accessing the
175: * <code>BLOB</code> value or if pos is less than 1
176: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
177: * this method
178: * @see #getBytes
179: * @since 1.4
180: */
181: int setBytes(long pos, byte[] bytes) throws SQLException;
182:
183: /**
184: * Writes all or part of the given <code>byte</code> array to the
185: * <code>BLOB</code> value that this <code>Blob</code> object represents
186: * and returns the number of bytes written.
187: * Writing starts at position <code>pos</code> in the <code>BLOB</code>
188: * value; <code>len</code> bytes from the given byte array are written.
189: * The array of bytes will overwrite the existing bytes
190: * in the <code>Blob</code> object starting at the position
191: * <code>pos</code>. If the end of the <code>Blob</code> value is reached
192: * while writing the array of bytes, then the length of the <code>Blob</code>
193: * value will be increased to accomodate the extra bytes.
194: * <p>
195: * <b>Note:</b> If the value specified for <code>pos</code>
196: * is greater then the length+1 of the <code>BLOB</code> value then the
197: * behavior is undefined. Some JDBC drivers may throw a
198: * <code>SQLException</code> while other drivers may support this
199: * operation.
200: *
201: * @param pos the position in the <code>BLOB</code> object at which
202: * to start writing; the first position is 1
203: * @param bytes the array of bytes to be written to this <code>BLOB</code>
204: * object
205: * @param offset the offset into the array <code>bytes</code> at which
206: * to start reading the bytes to be set
207: * @param len the number of bytes to be written to the <code>BLOB</code>
208: * value from the array of bytes <code>bytes</code>
209: * @return the number of bytes written
210: * @exception SQLException if there is an error accessing the
211: * <code>BLOB</code> value or if pos is less than 1
212: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
213: * this method
214: * @see #getBytes
215: * @since 1.4
216: */
217: int setBytes(long pos, byte[] bytes, int offset, int len)
218: throws SQLException;
219:
220: /**
221: * Retrieves a stream that can be used to write to the <code>BLOB</code>
222: * value that this <code>Blob</code> object represents. The stream begins
223: * at position <code>pos</code>.
224: * The bytes written to the stream will overwrite the existing bytes
225: * in the <code>Blob</code> object starting at the position
226: * <code>pos</code>. If the end of the <code>Blob</code> value is reached
227: * while writing to the stream, then the length of the <code>Blob</code>
228: * value will be increased to accomodate the extra bytes.
229: * <p>
230: * <b>Note:</b> If the value specified for <code>pos</code>
231: * is greater then the length+1 of the <code>BLOB</code> value then the
232: * behavior is undefined. Some JDBC drivers may throw a
233: * <code>SQLException</code> while other drivers may support this
234: * operation.
235: *
236: * @param pos the position in the <code>BLOB</code> value at which
237: * to start writing; the first position is 1
238: * @return a <code>java.io.OutputStream</code> object to which data can
239: * be written
240: * @exception SQLException if there is an error accessing the
241: * <code>BLOB</code> value or if pos is less than 1
242: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
243: * this method
244: * @see #getBinaryStream
245: * @since 1.4
246: */
247: java.io.OutputStream setBinaryStream(long pos) throws SQLException;
248:
249: /**
250: * Truncates the <code>BLOB</code> value that this <code>Blob</code>
251: * object represents to be <code>len</code> bytes in length.
252: * <p>
253: * <b>Note:</b> If the value specified for <code>pos</code>
254: * is greater then the length+1 of the <code>BLOB</code> value then the
255: * behavior is undefined. Some JDBC drivers may throw a
256: * <code>SQLException</code> while other drivers may support this
257: * operation.
258: *
259: * @param len the length, in bytes, to which the <code>BLOB</code> value
260: * that this <code>Blob</code> object represents should be truncated
261: * @exception SQLException if there is an error accessing the
262: * <code>BLOB</code> value or if len is less than 0
263: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
264: * this method
265: * @since 1.4
266: */
267: void truncate(long len) throws SQLException;
268:
269: /**
270: * This method frees the <code>Blob</code> object and releases the resources that
271: * it holds. The object is invalid once the <code>free</code>
272: * method is called.
273: *<p>
274: * After <code>free</code> has been called, any attempt to invoke a
275: * method other than <code>free</code> will result in a <code>SQLException</code>
276: * being thrown. If <code>free</code> is called multiple times, the subsequent
277: * calls to <code>free</code> are treated as a no-op.
278: *<p>
279: *
280: * @throws SQLException if an error occurs releasing
281: * the Blob's resources
282: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
283: * this method
284: * @since 1.6
285: */
286: void free() throws SQLException;
287:
288: /**
289: * Returns an <code>InputStream</code> object that contains a partial <code>Blob</code> value,
290: * starting with the byte specified by pos, which is length bytes in length.
291: *
292: * @param pos the offset to the first byte of the partial value to be retrieved.
293: * The first byte in the <code>Blob</code> is at position 1
294: * @param length the length in bytes of the partial value to be retrieved
295: * @return <code>InputStream</code> through which the partial <code>Blob</code> value can be read.
296: * @throws SQLException if pos is less than 1 or if pos is greater than the number of bytes
297: * in the <code>Blob</code> or if pos + length is greater than the number of bytes
298: * in the <code>Blob</code>
299: *
300: * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
301: * this method
302: * @since 1.6
303: */
304: InputStream getBinaryStream(long pos, long length)
305: throws SQLException;
306: }
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