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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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 *

 * You should have received a copy of the GNU General Public License version

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package java.sql;

import java.io.Reader;

/**

 * 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 <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 <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 <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 <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

   * <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

   * <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 <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 <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

     * <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 <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 <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 <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 <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;

}