https://openjdk.java.net/ 
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package java.sql;

import java.io.Reader;


The mapping in the Java™ 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™ programming language
 * for the SQL {@code CLOB} type.
 * An SQL {@code 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 {@code Clob} object using an SQL
 * {@code locator(CLOB)}, which means that a {@code Clob} object
 * contains a logical pointer to the SQL {@code CLOB} data rather than
 * the data itself. A {@code Clob} object is valid for the duration
 * of the transaction in which it was created.
 * <P>The {@code Clob} interface provides methods for getting the
 * length of an SQL {@code CLOB} (Character Large Object) value,
 * for materializing a {@code CLOB} value on the client, and for
 * searching for a substring or {@code CLOB} object within a
 * {@code CLOB} value.
 * Methods in the interfaces {@link ResultSet},
 * {@link CallableStatement}, and {@link PreparedStatement}, such as
 * {@code getClob} and {@code setClob} allow a programmer to
 * access an SQL {@code CLOB} value.  In addition, this interface
 * has methods for updating a {@code CLOB} value.
 * <p>
 * All methods on the {@code Clob} 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} value
   * designated by this {@code Clob} object.
   *
   * @return length of the {@code CLOB} in characters
   * @exception SQLException if there is an error accessing the
   *            length of the {@code CLOB} 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} value
   * designated by this {@code Clob} object.
   * The substring begins at position
   * {@code pos} and has up to {@code length} 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} that is the specified substring in
   *         the {@code CLOB} value designated by this {@code Clob} object
   * @exception SQLException if there is an error accessing the
   *            {@code CLOB} 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} value designated by this {@code Clob}
   * object as a {@code java.io.Reader} object (or as a stream of
   * characters).
   *
   * @return a {@code java.io.Reader} object containing the
   *         {@code CLOB} data
   * @exception SQLException if there is an error accessing the
   *            {@code CLOB} 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} value designated by this {@code Clob}
   * object as an ascii stream.
   *
   * @return a {@code java.io.InputStream} object containing the
   *         {@code CLOB} data
   * @exception SQLException if there is an error accessing the
   *            {@code CLOB} 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} appears in the SQL {@code CLOB} value
   * represented by this {@code Clob} object.  The search
   * begins at position {@code start}.
   *
   * @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} 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} object {@code searchstr} appears in this
   * {@code Clob} object.  The search begins at position
   * {@code start}.
   *
   * @param searchstr the {@code Clob} 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} 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} 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 accommodate the extra characters. 

Note: If the value specified for pos is greater than the length+1 of the CLOB value then the behavior is undefined. Some JDBC drivers may throw an 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} to the {@code CLOB}
     * value that this {@code Clob} object designates at the position
     * {@code pos}. The string will overwrite the existing characters
     * in the {@code Clob} object starting at the position
     * {@code pos}.  If the end of the {@code Clob} value is reached
     * while writing the given string, then the length of the {@code Clob}
     * value will be increased to accommodate the extra characters.
     * <p>
     * <b>Note:</b> If the value specified for {@code pos}
     * is greater than the length+1 of the {@code CLOB} value then the
     * behavior is undefined. Some JDBC drivers may throw an
     * {@code SQLException} while other drivers may support this
     * operation.
     *
     * @param pos the position at which to start writing to the {@code CLOB}
     *        value that this {@code Clob} object represents;
     *        the first position is 1.
     * @param str the string to be written to the {@code CLOB}
     *        value that this {@code Clob} designates
     * @return the number of characters written
     * @exception SQLException if there is an error accessing the
     *            {@code CLOB} 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 accommodate the extra characters. 

Note: If the value specified for pos is greater than the length+1 of the CLOB value then the behavior is undefined. Some JDBC drivers may throw an 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} characters of {@code str}, starting
     * at character {@code offset}, to the {@code CLOB} value
     * that this {@code Clob} represents.
     * The string will overwrite the existing characters
     * in the {@code Clob} object starting at the position
     * {@code pos}.  If the end of the {@code Clob} value is reached
     * while writing the given string, then the length of the {@code Clob}
     * value will be increased to accommodate the extra characters.
     * <p>
     * <b>Note:</b> If the value specified for {@code pos}
     * is greater than the length+1 of the {@code CLOB} value then the
     * behavior is undefined. Some JDBC drivers may throw an
     * {@code SQLException} while other drivers may support this
     * operation.
     *
     * @param pos the position at which to start writing to this
     *        {@code CLOB} object; The first position  is 1
     * @param str the string to be written to the {@code CLOB}
     *        value that this {@code Clob} object represents
     * @param offset the offset into {@code str} 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} 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 accommodate the extra characters. 

Note: If the value specified for pos is greater than the length+1 of the CLOB value then the behavior is undefined. Some JDBC drivers may throw an 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} value that this {@code Clob} object represents,
     * starting at position {@code pos}.  Characters written to the stream
     * will overwrite the existing characters
     * in the {@code Clob} object starting at the position
     * {@code pos}.  If the end of the {@code Clob} value is reached
     * while writing characters to the stream, then the length of the {@code Clob}
     * value will be increased to accommodate the extra characters.
     * <p>
     * <b>Note:</b> If the value specified for {@code pos}
     * is greater than the length+1 of the {@code CLOB} value then the
     * behavior is undefined. Some JDBC drivers may throw an
     * {@code SQLException} while other drivers may support this
     * operation.
     *
     * @param pos the position at which to start writing to this
     *        {@code CLOB} 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} 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 accommodate the extra characters. 

Note: If the value specified for pos is greater than the length+1 of the CLOB value then the behavior is undefined. Some JDBC drivers may throw an 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} value that this {@code Clob} object
     * represents, at position {@code pos}. Characters written to the stream
     * will overwrite the existing characters
     * in the {@code Clob} object starting at the position
     * {@code pos}.  If the end of the {@code Clob} value is reached
     * while writing characters to the stream, then the length of the {@code Clob}
     * value will be increased to accommodate the extra characters.
     * <p>
     * <b>Note:</b> If the value specified for {@code pos}
     * is greater than the length+1 of the {@code CLOB} value then the
     * behavior is undefined. Some JDBC drivers may throw an
     * {@code SQLException} while other drivers may support this
     * operation.
     *
     * @param  pos the position at which to start writing to the
     *        {@code CLOB} 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} 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 than the length+1 of the CLOB value then the behavior is undefined. Some JDBC drivers may throw an 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} value that this {@code Clob}
     * designates to have a length of {@code len}
     * characters.
     * <p>
     * <b>Note:</b> If the value specified for {@code pos}
     * is greater than the length+1 of the {@code CLOB} value then the
     * behavior is undefined. Some JDBC drivers may throw an
     * {@code SQLException} while other drivers may support this
     * operation.
     *
     * @param len the length, in characters, to which the {@code CLOB} value
     *        should be truncated
     * @exception SQLException if there is an error accessing the
     *            {@code CLOB} 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 releases the resources that the Clob object 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 releases the resources that the {@code Clob} object
     * holds.  The object is invalid once the {@code free} method
     * is called.
     * <p>
     * After {@code free} has been called, any attempt to invoke a
     * method other than {@code free} will result in a {@code SQLException}
     * being thrown.  If {@code free} is called multiple times, the subsequent
     * calls to {@code free} are treated as a no-op.
     *
     * @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} object that contains
     * a partial {@code Clob} 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} through which
     *         the partial {@code Clob} 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};
     *         or if pos + length is greater than the number of
     *         characters in the {@code Clob}
     *
     * @exception SQLFeatureNotSupportedException if the JDBC driver
     *            does not support this method
     * @since 1.6
     */
    Reader getCharacterStream(long pos, long length) throws SQLException;

}