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 * Copyright (c) 1998, 2013, 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.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package java.sql;

import java.io.InputStream;

/**

 * The representation (mapping) in

 * the Java™ programming language of an SQL

 * {@code BLOB} value.  An SQL {@code BLOB} is a built-in type

 * that stores a Binary Large Object as a column value in a row of

 * a database table. By default drivers implement {@code Blob} using

 * an SQL {@code locator(BLOB)}, which means that a

 * {@code Blob} object contains a logical pointer to the

 * SQL {@code BLOB} data rather than the data itself.

 * A {@code Blob} object is valid for the duration of the

 * transaction in which is was created.

 *

 * <P>Methods in the interfaces {@link ResultSet},

 * {@link CallableStatement}, and {@link PreparedStatement}, such as

 * {@code getBlob} and {@code setBlob} allow a programmer to

 * access an SQL {@code BLOB} value.

 * The {@code Blob} interface provides methods for getting the

 * length of an SQL {@code BLOB} (Binary Large Object) value,

 * for materializing a {@code BLOB} value on the client, and for

 * determining the position of a pattern of bytes within a

 * {@code BLOB} value. In addition, this interface has methods for updating

 * a {@code BLOB} value.

 * <p>

 * All methods on the {@code Blob} interface must be fully implemented if the

 * JDBC driver supports the data type.

 *

 * @since 1.2

 */

public interface Blob {

  /**

   * Returns the number of bytes in the {@code BLOB} value

   * designated by this {@code Blob} object.

   *

   * @return length of the {@code BLOB} in bytes

   * @exception SQLException if there is an error accessing the

   *            length of the {@code BLOB}

   * @exception SQLFeatureNotSupportedException if the JDBC driver

   *            does not support this method

   * @since 1.2

   */

  long length() throws SQLException;

  /**

   * Retrieves all or part of the {@code BLOB}

   * value that this {@code Blob} object represents, as an array of

   * bytes.  This {@code byte} array contains up to {@code length}

   * consecutive bytes starting at position {@code pos}.

   *

   * @param pos the ordinal position of the first byte in the

   *        {@code BLOB} value to be extracted; the first byte is at

   *        position 1

   * @param length the number of consecutive bytes to be copied; the value

   *        for length must be 0 or greater

   * @return a byte array containing up to {@code length}

   *         consecutive bytes from the {@code BLOB} value designated

   *         by this {@code Blob} object, starting with the

   *         byte at position {@code pos}

   * @exception SQLException if there is an error accessing the

   *            {@code BLOB} value; if pos is less than 1 or length is

   *            less than 0

   * @exception SQLFeatureNotSupportedException if the JDBC driver

   *            does not support this method

   * @see #setBytes

   * @since 1.2

   */

  byte[] getBytes(long pos, int length) throws SQLException;

  /**

   * Retrieves the {@code BLOB} value designated by this

   * {@code Blob} instance as a stream.

   *

   * @return a stream containing the {@code BLOB} data

   * @exception SQLException if there is an error accessing the

   *            {@code BLOB} value

   * @exception SQLFeatureNotSupportedException if the JDBC driver

   *            does not support this method

   * @see #setBinaryStream

   * @since 1.2

   */

  java.io.InputStream getBinaryStream () throws SQLException;

  /**

   * Retrieves the byte position at which the specified byte array

   * {@code pattern} begins within the {@code BLOB}

   * value that this {@code Blob} object represents.

   * The search for {@code pattern} begins at position

   * {@code start}.

   *

   * @param pattern the byte array for which to search

   * @param start the position at which to begin searching; the

   *        first position is 1

   * @return the position at which the pattern appears, else -1

   * @exception SQLException if there is an error accessing the

   *            {@code BLOB} or if start is less than 1

   * @exception SQLFeatureNotSupportedException if the JDBC driver

   *            does not support this method

   * @since 1.2

   */

  long position(byte pattern[], long start) throws SQLException;

  /**

   * Retrieves the byte position in the {@code BLOB} value

   * designated by this {@code Blob} object at which

   * {@code pattern} begins.  The search begins at position

   * {@code start}.

   *

   * @param pattern the {@code Blob} object designating

   *        the {@code BLOB} value for which to search

   * @param start the position in the {@code BLOB} value

   *        at which to begin searching; the first position is 1

   * @return the position at which the pattern begins, else -1

   * @exception SQLException if there is an error accessing the

   *            {@code BLOB} value or if start is less than 1

   * @exception SQLFeatureNotSupportedException if the JDBC driver

   *            does not support this method

   * @since 1.2

   */

  long position(Blob pattern, long start) throws SQLException;

    // -------------------------- JDBC 3.0 -----------------------------------

    /**

     * Writes the given array of bytes to the {@code BLOB} value that

     * this {@code Blob} object represents, starting at position

     * {@code pos}, and returns the number of bytes written.

     * The array of bytes will overwrite the existing bytes

     * in the {@code Blob} object starting at the position

     * {@code pos}.  If the end of the {@code Blob} value is reached

     * while writing the array of bytes, then the length of the {@code Blob}

     * value will be increased to accommodate the extra bytes.

     * <p>

     * <b>Note:</b> If the value specified for {@code pos}

     * is greater than the length+1 of the {@code BLOB} 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 in the {@code BLOB} object at which

     *        to start writing; the first position is 1

     * @param bytes the array of bytes to be written to the {@code BLOB}

     *        value that this {@code Blob} object represents

     * @return the number of bytes written

     * @exception SQLException if there is an error accessing the

     *            {@code BLOB} value or if pos is less than 1

     * @exception SQLFeatureNotSupportedException if the JDBC driver

     *            does not support this method

     * @see #getBytes

     * @since 1.4

     */

    int setBytes(long pos, byte[] bytes) throws SQLException;

    /**

     * Writes all or part of the given {@code byte} array to the

     * {@code BLOB} value that this {@code Blob} object represents

     * and returns the number of bytes written.

     * Writing starts at position {@code pos} in the {@code BLOB}

     * value; {@code len} bytes from the given byte array are written.

     * The array of bytes will overwrite the existing bytes

     * in the {@code Blob} object starting at the position

     * {@code pos}.  If the end of the {@code Blob} value is reached

     * while writing the array of bytes, then the length of the {@code Blob}

     * value will be increased to accommodate the extra bytes.

     * <p>

     * <b>Note:</b> If the value specified for {@code pos}

     * is greater than the length+1 of the {@code BLOB} 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 in the {@code BLOB} object at which

     *        to start writing; the first position is 1

     * @param bytes the array of bytes to be written to this {@code BLOB}

     *        object

     * @param offset the offset into the array {@code bytes} at which

     *        to start reading the bytes to be set

     * @param len the number of bytes to be written to the {@code BLOB}

     *        value from the array of bytes {@code bytes}

     * @return the number of bytes written

     * @exception SQLException if there is an error accessing the

     *            {@code BLOB} value or if pos is less than 1

     * @exception SQLFeatureNotSupportedException if the JDBC driver

     *            does not support this method

     * @see #getBytes

     * @since 1.4

     */

    int setBytes(long pos, byte[] bytes, int offset, int len) throws SQLException;

    /**

     * Retrieves a stream that can be used to write to the {@code BLOB}

     * value that this {@code Blob} object represents.  The stream begins

     * at position {@code pos}.

     * The  bytes written to the stream will overwrite the existing bytes

     * in the {@code Blob} object starting at the position

     * {@code pos}.  If the end of the {@code Blob} value is reached

     * while writing to the stream, then the length of the {@code Blob}

     * value will be increased to accommodate the extra bytes.

     * <p>

     * <b>Note:</b> If the value specified for {@code pos}

     * is greater than the length+1 of the {@code BLOB} 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 in the {@code BLOB} value at which

     *        to start writing; the first position is 1

     * @return a {@code java.io.OutputStream} object to which data can

     *         be written

     * @exception SQLException if there is an error accessing the

     *            {@code BLOB} value or if pos is less than 1

     * @exception SQLFeatureNotSupportedException if the JDBC driver

     *            does not support this method

     * @see #getBinaryStream

     * @since 1.4

     */

    java.io.OutputStream setBinaryStream(long pos) throws SQLException;

    /**

     * Truncates the {@code BLOB} value that this {@code Blob}

     * object represents to be {@code len} bytes in length.

     * <p>

     * <b>Note:</b> If the value specified for {@code pos}

     * is greater than the length+1 of the {@code BLOB} 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 bytes, to which the {@code BLOB} value

     *        that this {@code Blob} object represents should be truncated

     * @exception SQLException if there is an error accessing the

     *            {@code BLOB} 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 Blob} object and releases the resources that

     * it 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 an {@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 Blob's resources

     * @exception SQLFeatureNotSupportedException if the JDBC driver

     *            does not support this method

     * @since 1.6

     */

    void free() throws SQLException;

    /**

     * Returns an {@code InputStream} object that contains

     * a partial {@code Blob} value, starting with the byte

     * specified by pos, which is length bytes in length.

     *

     * @param pos the offset to the first byte of the partial value to be

     *        retrieved. The first byte in the {@code Blob} is at position 1.

     * @param length the length in bytes of the partial value to be retrieved

     * @return {@code InputStream} through which

     *         the partial {@code Blob} value can be read.

     * @throws SQLException if pos is less than 1 or if pos is greater

     *         than the number of bytes in the {@code Blob} or if

     *         pos + length is greater than the number of bytes

     *         in the {@code Blob}

     *

     * @exception SQLFeatureNotSupportedException if the JDBC driver

     *            does not support this method

     * @since 1.6

     */

    InputStream getBinaryStream(long pos, long length) throws SQLException;

}