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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;
}