001/* Clob.java -- Access Character Large OBjects
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
038
039package java.sql;
040
041import java.io.InputStream;
042import java.io.OutputStream;
043import java.io.Reader;
044import java.io.Writer;
045
046/**
047 * This interface contains methods for accessing a SQL CLOB (Character Large
048 * OBject) type.
049 * 
050 * @author Aaron M. Renn (arenn@urbanophile.com)
051 */
052public interface Clob
053{
054  /**
055   * This method returns the number of characters in this <code>Clob</code>.
056   * 
057   * @return The number of characters in this <code>Clob</code>.
058   * @exception SQLException If an error occurs.
059   * @since 1.2
060   */
061  long length() throws SQLException;
062
063  /**
064   * This method returns the specified portion of this <code>Clob</code> as a
065   * <code>String</code>.
066   * 
067   * @param start The index into this <code>Clob</code> (index values
068   *              start at 1) to start returning characters from.
069   * @param count The requested number of characters to return.
070   * @return The requested <code>Clob</code> section, as a <code>String</code>.
071   * @exception SQLException If an error occurs.
072   * @since 1.2
073   */
074  String getSubString(long start, int count) throws SQLException;
075
076  /**
077   * This method returns a character stream that reads the contents of this
078   * <code>Clob</code>.
079   * 
080   * @return A character stream to read this <code>Clob</code>'s contents.
081   * @exception SQLException If an error occurs.
082   * @since 1.2
083   */
084  Reader getCharacterStream() throws SQLException;
085
086  /**
087   * This method returns a byte stream that reads the contents of this
088   * <code>Clob</code> as a series of ASCII bytes.
089   * 
090   * @return A stream to read this <code>Clob</code>'s contents.
091   * @exception SQLException If an error occurs.
092   * @since 1.2
093   */
094  InputStream getAsciiStream() throws SQLException;
095
096  /**
097   * This method returns the index into this <code>Clob</code> of the first
098   * occurrence of the specified character pattern (supplied by the caller as a
099   * <code>String</code>). The search begins at the specified index.
100   * 
101   * @param pattern The character pattern to search for, passed as a
102   *                <code>String</code>.
103   * @param start The index into this <code>Clob</code> to start searching
104   *              (indices start at 1).
105   * @return The index at which the pattern was found (indices start at 1), or
106   *         -1 if the pattern was not found.
107   * @exception SQLException If an error occurs.
108   * @since 1.2
109   */
110  long position(String pattern, long start) throws SQLException;
111
112  /**
113   * This method returns the index into this <code>Clob</code> of the first
114   * occurrence of the specified character pattern (supplied by the caller as a
115   * <code>Clob</code>). The search begins at the specified index.
116   * 
117   * @param pattern The character pattern to search for, passed as a
118   *                <code>Clob</code>.
119   * @param start The index into this <code>Clob</code> to start searching
120   *              (indices start at 1).
121   * @return The index at which the pattern was found (indices start at 1), or
122   *         -1 if the pattern was not found.
123   * @exception SQLException If an error occurs.
124   * @since 1.2
125   */
126  long position(Clob pattern, long start) throws SQLException;
127
128  /**
129   * Writes the specified string into this <code>Clob</code>, starting at the
130   * specified index.
131   * 
132   * @param start The index at which the writing starts.
133   * @param value The string to write.
134   * @return The number of characters written.
135   * @exception SQLException If an error occurs.
136   * @since 1.4
137   */
138  int setString(long start, String value) throws SQLException;
139
140  /**
141   * Writes the specified portion of a string into this <code>Clob</code>,
142   * starting at the specified index.
143   * 
144   * @param startWrite The index at which the writing starts.
145   * @param value The string to write a portion of.
146   * @param startRead The offset into the string where the portion to copy
147   *                  starts.
148   * @param count The number of characters to write.
149   * @return The number of characters written.
150   * @exception SQLException If an error occurs.
151   * @since 1.4
152   */
153  int setString(long startWrite, String value, int startRead, int count)
154      throws SQLException;
155
156  /**
157   * Returns an ASCII text stream that writes into this <code>Clob</code>,
158   * starting at the specified index.
159   * 
160   * @param start The index at which the writing starts.
161   * @return An ASCII text stream to write into this <code>Clob</code>.
162   * @exception SQLException If an error occurs.
163   * @since 1.4
164   */
165  OutputStream setAsciiStream(long start) throws SQLException;
166
167  /**
168   * Returns a character stream that writes into this <code>Clob</code>,
169   * starting at the specified index.
170   * 
171   * @param start The index at which the writing starts.
172   * @return A character stream to write into this <code>Clob</code>.
173   * @exception SQLException If an error occurs.
174   * @since 1.4
175   */
176  Writer setCharacterStream(long start) throws SQLException;
177
178  /**
179   * Truncates this <code>Clob</code> to be at most the specified number of
180   * characters long.
181   * 
182   * @param count The length this <code>Clob</code> is truncated to.
183   * @exception SQLException If an error occurs.
184   * @since 1.4
185   */
186  void truncate(long count) throws SQLException;
187}