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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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 *
 * 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,
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 *
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package java.sql;

import java.io.Reader;

/**
 * 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 {@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 {@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 {@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 {@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
 * {@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
 * {@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 {@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 {@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
 * {@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 {@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 {@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 {@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 {@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;

}