https://openjdk.java.net/ 
/*
 * Copyright (c) 1998, 2006, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package java.sql;

import java.io.Reader;


The mapping in the JavaTM programming language
for the SQL CLOB type.
An SQL CLOB is a built-in type
that stores a Character Large Object as a column value in a row of
a database table.
By default drivers implement a Clob object using an SQL
locator(CLOB), which means that a Clob object
contains a logical pointer to the SQL CLOB data rather than
the data itself. A Clob object is valid for the duration
of the transaction in which it was created.

The Clob interface provides methods for getting the
length of an SQL CLOB (Character Large Object) value,
for materializing a CLOB value on the client, and for
searching for a substring or CLOB object within a
CLOB value. Methods in the interfaces ResultSet, CallableStatement, and PreparedStatement, such as getClob and setClob allow a programmer to
access an SQL CLOB value.  In addition, this interface
has methods for updating a CLOB value.


All methods on the Clob interface must be fully implemented if the
JDBC driver supports the data type.

Since:1.2
/**
 * The mapping in the Java<sup><font size=-2>TM</font></sup> programming language
 * for the SQL <code>CLOB</code> type.
 * An SQL <code>CLOB</code> is a built-in type
 * that stores a Character Large Object as a column value in a row of
 * a database table.
 * By default drivers implement a <code>Clob</code> object using an SQL
 * <code>locator(CLOB)</code>, which means that a <code>Clob</code> object
 * contains a logical pointer to the SQL <code>CLOB</code> data rather than
 * the data itself. A <code>Clob</code> object is valid for the duration
 * of the transaction in which it was created.
 * <P>The <code>Clob</code> interface provides methods for getting the
 * length of an SQL <code>CLOB</code> (Character Large Object) value,
 * for materializing a <code>CLOB</code> value on the client, and for
 * searching for a substring or <code>CLOB</code> object within a
 * <code>CLOB</code> value.
 * Methods in the interfaces {@link ResultSet},
 * {@link CallableStatement}, and {@link PreparedStatement}, such as
 * <code>getClob</code> and <code>setClob</code> allow a programmer to
 * access an SQL <code>CLOB</code> value.  In addition, this interface
 * has methods for updating a <code>CLOB</code> value.
 * <p>
 * All methods on the <code>Clob</code> interface must be fully implemented if the
 * JDBC driver supports the data type.
 *
 * @since 1.2
 */

public interface Clob {

  
Retrieves the number of characters
in the CLOB value
designated by this Clob object.

Throws:
Returns:length of the CLOB in characters
Since:1.2
/**
   * Retrieves the number of characters
   * in the <code>CLOB</code> value
   * designated by this <code>Clob</code> object.
   *
   * @return length of the <code>CLOB</code> in characters
   * @exception SQLException if there is an error accessing the
   *            length of the <code>CLOB</code> value
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @since 1.2
   */
  long length() throws SQLException;

  
Retrieves a copy of the specified substring
in the CLOB value
designated by this Clob object.
The substring begins at position
pos and has up to length consecutive
characters.

Params:
  • pos – the first character of the substring to be extracted.
           The first character is at position 1.
  • length – the number of consecutive characters to be copied;
the value for length must be 0 or greater
Throws:
Returns:a String that is the specified substring in
        the CLOB value designated by this Clob object
Since:1.2
/**
   * Retrieves a copy of the specified substring
   * in the <code>CLOB</code> value
   * designated by this <code>Clob</code> object.
   * The substring begins at position
   * <code>pos</code> and has up to <code>length</code> consecutive
   * characters.
   *
   * @param pos the first character of the substring to be extracted.
   *            The first character is at position 1.
   * @param length the number of consecutive characters to be copied;
   * the value for length must be 0 or greater
   * @return a <code>String</code> that is the specified substring in
   *         the <code>CLOB</code> value designated by this <code>Clob</code> object
   * @exception SQLException if there is an error accessing the
   *            <code>CLOB</code> value; if pos is less than 1 or length is
   * less than 0
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @since 1.2
   */
  String getSubString(long pos, int length) throws SQLException;

  
Retrieves the CLOB value designated by this Clob
object as a java.io.Reader object (or as a stream of
characters).

Throws:
See Also:
Returns:a java.io.Reader object containing the
        CLOB data
Since:1.2
/**
   * Retrieves the <code>CLOB</code> value designated by this <code>Clob</code>
   * object as a <code>java.io.Reader</code> object (or as a stream of
   * characters).
   *
   * @return a <code>java.io.Reader</code> object containing the
   *         <code>CLOB</code> data
   * @exception SQLException if there is an error accessing the
   *            <code>CLOB</code> value
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @see #setCharacterStream
   * @since 1.2
   */
  java.io.Reader getCharacterStream() throws SQLException;

  
Retrieves the CLOB value designated by this Clob
object as an ascii stream.

Throws:
See Also:
Returns:a java.io.InputStream object containing the
        CLOB data
Since:1.2
/**
   * Retrieves the <code>CLOB</code> value designated by this <code>Clob</code>
   * object as an ascii stream.
   *
   * @return a <code>java.io.InputStream</code> object containing the
   *         <code>CLOB</code> data
   * @exception SQLException if there is an error accessing the
   *            <code>CLOB</code> value
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @see #setAsciiStream
   * @since 1.2
   */
  java.io.InputStream getAsciiStream() throws SQLException;

  
Retrieves the character position at which the specified substring
searchstr appears in the SQL CLOB value
represented by this Clob object.  The search
begins at position start.

Params:
  • searchstr – the substring for which to search
  • start – the position at which to begin searching; the first position
             is 1
Throws:
Returns:the position at which the substring appears or -1 if it is not
        present; the first position is 1
Since:1.2
/**
   * Retrieves the character position at which the specified substring
   * <code>searchstr</code> appears in the SQL <code>CLOB</code> value
   * represented by this <code>Clob</code> object.  The search
   * begins at position <code>start</code>.
   *
   * @param searchstr the substring for which to search
   * @param start the position at which to begin searching; the first position
   *              is 1
   * @return the position at which the substring appears or -1 if it is not
   *         present; the first position is 1
   * @exception SQLException if there is an error accessing the
   *            <code>CLOB</code> value or if pos is less than 1
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @since 1.2
   */
  long position(String searchstr, long start) throws SQLException;

  
Retrieves the character position at which the specified
Clob object searchstr appears in this
Clob object.  The search begins at position
start.

Params:
  • searchstr – the Clob object for which to search
  • start – the position at which to begin searching; the first
             position is 1
Throws:
Returns:the position at which the Clob object appears
             or -1 if it is not present; the first position is 1
Since:1.2
/**
   * Retrieves the character position at which the specified
   * <code>Clob</code> object <code>searchstr</code> appears in this
   * <code>Clob</code> object.  The search begins at position
   * <code>start</code>.
   *
   * @param searchstr the <code>Clob</code> object for which to search
   * @param start the position at which to begin searching; the first
   *              position is 1
   * @return the position at which the <code>Clob</code> object appears
   *              or -1 if it is not present; the first position is 1
   * @exception SQLException if there is an error accessing the
   *            <code>CLOB</code> value or if start is less than 1
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @since 1.2
   */
  long position(Clob searchstr, long start) throws SQLException;

    //---------------------------- jdbc 3.0 -----------------------------------

    
Writes the given Java String to the CLOB
value that this Clob object designates at the position
pos. The string will overwrite the existing characters
in the Clob object starting at the position
pos.  If the end of the Clob value is reached
while writing the given string, then the length of the Clob
value will be increased to accomodate the extra characters.


Note: If the value specified for pos
is greater then the length+1 of the CLOB value then the
behavior is undefined. Some JDBC drivers may throw a
SQLException while other drivers may support this
operation.

Params:
  • pos – the position at which to start writing to the CLOB
        value that this Clob object represents;
The first position is 1
  • str – the string to be written to the CLOB
       value that this Clob designates
Throws:
Returns:the number of characters written
Since:1.4
/**
     * Writes the given Java <code>String</code> to the <code>CLOB</code>
     * value that this <code>Clob</code> object designates at the position
     * <code>pos</code>. The string will overwrite the existing characters
     * in the <code>Clob</code> object starting at the position
     * <code>pos</code>.  If the end of the <code>Clob</code> value is reached
     * while writing the given string, then the length of the <code>Clob</code>
     * value will be increased to accomodate the extra characters.
     * <p>
     * <b>Note:</b> If the value specified for <code>pos</code>
     * is greater then the length+1 of the <code>CLOB</code> value then the
     * behavior is undefined. Some JDBC drivers may throw a
     * <code>SQLException</code> while other drivers may support this
     * operation.
     *
     * @param pos the position at which to start writing to the <code>CLOB</code>
     *         value that this <code>Clob</code> object represents;
     * The first position is 1
     * @param str the string to be written to the <code>CLOB</code>
     *        value that this <code>Clob</code> designates
     * @return the number of characters written
     * @exception SQLException if there is an error accessing the
     *            <code>CLOB</code> value or if pos is less than 1
     *
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @since 1.4
     */
    int setString(long pos, String str) throws SQLException;

    
Writes len characters of str, starting
at character offset, to the CLOB value
that this Clob represents.  The string will overwrite the existing characters
in the Clob object starting at the position
pos.  If the end of the Clob value is reached
while writing the given string, then the length of the Clob
value will be increased to accomodate the extra characters.


Note: If the value specified for pos
is greater then the length+1 of the CLOB value then the
behavior is undefined. Some JDBC drivers may throw a
SQLException while other drivers may support this
operation.

Params:
  • pos – the position at which to start writing to this
       CLOB object; The first position  is 1
  • str – the string to be written to the CLOB
       value that this Clob object represents
  • offset – the offset into str to start reading
       the characters to be written
  • len – the number of characters to be written
Throws:
Returns:the number of characters written
Since:1.4
/**
     * Writes <code>len</code> characters of <code>str</code>, starting
     * at character <code>offset</code>, to the <code>CLOB</code> value
     * that this <code>Clob</code> represents.  The string will overwrite the existing characters
     * in the <code>Clob</code> object starting at the position
     * <code>pos</code>.  If the end of the <code>Clob</code> value is reached
     * while writing the given string, then the length of the <code>Clob</code>
     * value will be increased to accomodate the extra characters.
     * <p>
     * <b>Note:</b> If the value specified for <code>pos</code>
     * is greater then the length+1 of the <code>CLOB</code> value then the
     * behavior is undefined. Some JDBC drivers may throw a
     * <code>SQLException</code> while other drivers may support this
     * operation.
     *
     * @param pos the position at which to start writing to this
     *        <code>CLOB</code> object; The first position  is 1
     * @param str the string to be written to the <code>CLOB</code>
     *        value that this <code>Clob</code> object represents
     * @param offset the offset into <code>str</code> to start reading
     *        the characters to be written
     * @param len the number of characters to be written
     * @return the number of characters written
     * @exception SQLException if there is an error accessing the
     *            <code>CLOB</code> value or if pos is less than 1
     *
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @since 1.4
     */
    int setString(long pos, String str, int offset, int len) throws SQLException;

    
Retrieves a stream to be used to write Ascii characters to the
CLOB value that this Clob object represents,
starting at position pos.  Characters written to the stream
will overwrite the existing characters
in the Clob object starting at the position
pos.  If the end of the Clob value is reached
while writing characters to the stream, then the length of the Clob
value will be increased to accomodate the extra characters.


Note: If the value specified for pos
is greater then the length+1 of the CLOB value then the
behavior is undefined. Some JDBC drivers may throw a
SQLException while other drivers may support this
operation.

Params:
  • pos – the position at which to start writing to this
       CLOB object; The first position is 1
Throws:
See Also:
Returns:the stream to which ASCII encoded characters can be written
Since:1.4
/**
     * Retrieves a stream to be used to write Ascii characters to the
     * <code>CLOB</code> value that this <code>Clob</code> object represents,
     * starting at position <code>pos</code>.  Characters written to the stream
     * will overwrite the existing characters
     * in the <code>Clob</code> object starting at the position
     * <code>pos</code>.  If the end of the <code>Clob</code> value is reached
     * while writing characters to the stream, then the length of the <code>Clob</code>
     * value will be increased to accomodate the extra characters.
     * <p>
     * <b>Note:</b> If the value specified for <code>pos</code>
     * is greater then the length+1 of the <code>CLOB</code> value then the
     * behavior is undefined. Some JDBC drivers may throw a
     * <code>SQLException</code> while other drivers may support this
     * operation.
     *
     * @param pos the position at which to start writing to this
     *        <code>CLOB</code> object; The first position is 1
     * @return the stream to which ASCII encoded characters can be written
     * @exception SQLException if there is an error accessing the
     *            <code>CLOB</code> value or if pos is less than 1
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @see #getAsciiStream
     *
     * @since 1.4
     */
    java.io.OutputStream setAsciiStream(long pos) throws SQLException;

    
Retrieves a stream to be used to write a stream of Unicode characters
to the CLOB value that this Clob object
represents, at position pos. Characters written to the stream
will overwrite the existing characters
in the Clob object starting at the position
pos.  If the end of the Clob value is reached
while writing characters to the stream, then the length of the Clob
value will be increased to accomodate the extra characters.


Note: If the value specified for pos
is greater then the length+1 of the CLOB value then the
behavior is undefined. Some JDBC drivers may throw a
SQLException while other drivers may support this
operation.

Params:
  • pos – the position at which to start writing to the
       CLOB value; The first position is 1
Throws:
See Also:
Returns:a stream to which Unicode encoded characters can be written
Since:1.4
/**
     * Retrieves a stream to be used to write a stream of Unicode characters
     * to the <code>CLOB</code> value that this <code>Clob</code> object
     * represents, at position <code>pos</code>. Characters written to the stream
     * will overwrite the existing characters
     * in the <code>Clob</code> object starting at the position
     * <code>pos</code>.  If the end of the <code>Clob</code> value is reached
     * while writing characters to the stream, then the length of the <code>Clob</code>
     * value will be increased to accomodate the extra characters.
     * <p>
     * <b>Note:</b> If the value specified for <code>pos</code>
     * is greater then the length+1 of the <code>CLOB</code> value then the
     * behavior is undefined. Some JDBC drivers may throw a
     * <code>SQLException</code> while other drivers may support this
     * operation.
     *
     * @param  pos the position at which to start writing to the
     *        <code>CLOB</code> value; The first position is 1
     *
     * @return a stream to which Unicode encoded characters can be written
     * @exception SQLException if there is an error accessing the
     *            <code>CLOB</code> value or if pos is less than 1
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @see #getCharacterStream
     *
     * @since 1.4
     */
    java.io.Writer setCharacterStream(long pos) throws SQLException;

    
Truncates the CLOB value that this Clob
designates to have a length of len
characters.


Note: If the value specified for pos
is greater then the length+1 of the CLOB value then the
behavior is undefined. Some JDBC drivers may throw a
SQLException while other drivers may support this
operation.

Params:
  • len – the length, in characters, to which the CLOB value
       should be truncated
Throws:
Since:1.4
/**
     * Truncates the <code>CLOB</code> value that this <code>Clob</code>
     * designates to have a length of <code>len</code>
     * characters.
     * <p>
     * <b>Note:</b> If the value specified for <code>pos</code>
     * is greater then the length+1 of the <code>CLOB</code> value then the
     * behavior is undefined. Some JDBC drivers may throw a
     * <code>SQLException</code> while other drivers may support this
     * operation.
     *
     * @param len the length, in characters, to which the <code>CLOB</code> value
     *        should be truncated
     * @exception SQLException if there is an error accessing the
     *            <code>CLOB</code> value or if len is less than 0
     *
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @since 1.4
     */
    void truncate(long len) throws SQLException;

    
This method frees the Clob object and releases the resources the resources
that it holds.  The object is invalid once the free method
is called.


After free has been called, any attempt to invoke a
method other than free will result in a SQLException
being thrown.  If free is called multiple times, the subsequent
calls to free are treated as a no-op.



Throws:
Since:1.6
/**
     * This method frees the <code>Clob</code> object and releases the resources the resources
     * that it holds.  The object is invalid once the <code>free</code> method
     * is called.
     * <p>
     * After <code>free</code> has been called, any attempt to invoke a
     * method other than <code>free</code> will result in a <code>SQLException</code>
     * being thrown.  If <code>free</code> is called multiple times, the subsequent
     * calls to <code>free</code> are treated as a no-op.
     * <p>
     * @throws SQLException if an error occurs releasing
     * the Clob's resources
     *
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @since 1.6
     */
    void free() throws SQLException;

    
Returns a Reader object that contains a partial Clob value, starting
with the character specified by pos, which is length characters in length.

Params:
  • pos – the offset to the first character of the partial value to
be retrieved.  The first character in the Clob is at position 1.
  • length – the length in characters of the partial value to be retrieved.
Throws:
  • SQLException – if pos is less than 1 or if pos is greater than the number of
characters in the Clob or if pos + length is greater than the number of
characters in the Clob
  • SQLFeatureNotSupportedException – if the JDBC driver does not support
this method
Returns:Reader through which the partial Clob value can be read.
Since:1.6
/**
     * Returns a <code>Reader</code> object that contains a partial <code>Clob</code> value, starting
     * with the character specified by pos, which is length characters in length.
     *
     * @param pos the offset to the first character of the partial value to
     * be retrieved.  The first character in the Clob is at position 1.
     * @param length the length in characters of the partial value to be retrieved.
     * @return <code>Reader</code> through which the partial <code>Clob</code> value can be read.
     * @throws SQLException if pos is less than 1 or if pos is greater than the number of
     * characters in the <code>Clob</code> or if pos + length is greater than the number of
     * characters in the <code>Clob</code>
     *
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @since 1.6
     */
    Reader getCharacterStream(long pos, long length) throws SQLException;

}