001/* Blob.java -- Access a SQL Binary Large OBject.
002   Copyright (C) 1999, 2000, 2002, 2006 Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038package java.sql;
039
040import java.io.InputStream;
041import java.io.OutputStream;
042
043/**
044 * This interface specified methods for accessing a SQL BLOB (Binary Large
045 * OBject) type.
046 *
047 * @author Aaron M. Renn (arenn@urbanophile.com)
048 * @since 1.2
049 */
050public interface Blob
051{
052  /**
053   * This method returns the number of bytes in this <code>Blob</code>.
054   *
055   * @return The number of bytes in this <code>Blob</code>.
056   * @exception SQLException If an error occurs.
057   */
058  long length() throws SQLException;
059
060  /**
061   * This method returns up to the requested bytes of this <code>Blob</code>
062   * as a <code>byte</code> array.
063   *
064   * @param start The index into this <code>Blob</code> to start returning
065   *              bytes from.
066   * @param count The requested number of bytes to return.
067   * @return The requested bytes from this <code>Blob</code>.
068   * @exception SQLException If an error occurs.
069   */
070  byte[] getBytes(long start, int count) throws SQLException;
071
072  /**
073   * This method returns a stream that will read the bytes of this
074   * <code>Blob</code>.
075   *
076   * @return A stream that will read the bytes of this <code>Blob</code>.
077   * @exception SQLException If an error occurs.
078   */
079  InputStream getBinaryStream() throws SQLException;
080
081  /**
082   * This method returns the index into this <code>Blob</code> at which the
083   * first instance of the specified bytes occur. The searching starts at the
084   * specified index into this <code>Blob</code>.
085   *
086   * @param pattern The byte pattern to search for.
087   * @param start The index into this <code>Blob</code> to start searching for
088   *              the pattern.
089   * @return The offset at which the pattern is first found, or -1 if the
090   *         pattern is not found.
091   * @exception SQLException If an error occurs.
092   */
093  long position(byte[] pattern, long start) throws SQLException;
094
095  /**
096   * This method returns the index into this <code>Blob</code> at which the
097   * first instance of the specified pattern occurs. The searching starts at the
098   * specified index into this <code>Blob</code>. The bytes in the specified
099   * <code>Blob</code> are used as the search pattern.
100   *
101   * @param pattern The <code>Blob</code> containing the byte pattern to
102   *                search for.
103   * @param start The index into this <code>Blob</code> to start searching for
104   *              the pattern.
105   * @return The offset at which the pattern is first found, or -1 if the
106   *         pattern is not found.
107   * @exception SQLException If an error occurs.
108   */
109  long position(Blob pattern, long start) throws SQLException;
110
111  /**
112   * Writes the specified data into this <code>Blob</code>, starting at the
113   * specified index.
114   *
115   * @param start The index at which the writing starts.
116   * @param bytes The data to write.
117   * @exception SQLException If an error occurs.
118   * @since 1.4
119   */
120  int setBytes(long start, byte[] bytes) throws SQLException;
121
122  /**
123   * Writes a portion of the specified data into this <code>Blob</code>,
124   * starting at the specified index.
125   *
126   * @param startWrite The index into this <code>Blob</code> at which writing
127   *                   starts.
128   * @param bytes The data to write a portion of.
129   * @param startRead The offset into the data where the portion to copy starts.
130   * @param count The number of bytes to write.
131   * @exception SQLException If an error occurs.
132   * @since 1.4
133   */
134  int setBytes(long startWrite, byte[] bytes, int startRead, int count)
135      throws SQLException;
136
137  /**
138   * Returns a binary stream that writes into this <code>Blob</code>,
139   * starting at the specified index.
140   *
141   * @param start The index at which the writing starts.
142   * @return A binary stream to write into this <code>Blob</code>.
143   * @exception SQLException If an error occurs.
144   * @since 1.4
145   */
146  OutputStream setBinaryStream(long start) throws SQLException;
147
148  /**
149   * Truncates this <code>Blob</code> to be at most the specified number of
150   * bytes long.
151   *
152   * @param count The length this <code>Blob</code> is truncated to.
153   * @exception SQLException If an error occurs.
154   * @since 1.4
155   */
156  void truncate(long count) throws SQLException;
157}