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	/*
	* Copyright (c) 1998, 2020, 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
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	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
	* @throws SQLException if there is an error accessing the
	* length of the {@code BLOB}
	* @throws 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}
	* @throws SQLException if there is an error accessing the
	* {@code BLOB} value; if pos is less than 1 or length is
	* less than 0
	* @throws 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
	* @throws SQLException if there is an error accessing the
	* {@code BLOB} value
	* @throws 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
	* @throws SQLException if there is an error accessing the
	* {@code BLOB} or if start is less than 1
	* @throws 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
	* @throws SQLException if there is an error accessing the
	* {@code BLOB} value or if start is less than 1
	* @throws 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
	* @throws SQLException if there is an error accessing the
	* {@code BLOB} value or if pos is less than 1
	* @throws 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
	* @throws SQLException if there is an error accessing the
	* {@code BLOB} value or if pos is less than 1
	* @throws 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
	* @throws SQLException if there is an error accessing the
	* {@code BLOB} value or if pos is less than 1
	* @throws 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
	* @throws SQLException if there is an error accessing the
	* {@code BLOB} value or if len is less than 0
	* @throws 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
	* @throws 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}
	*
	* @throws SQLFeatureNotSupportedException if the JDBC driver
	* does not support this method
	* @since 1.6
	*/
	InputStream getBinaryStream(long pos, long length) throws SQLException;
	}

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