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* 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<sup><font size=-2>TM</font></sup> programming
* language of an SQL
* <code>BLOB</code> value. An SQL <code>BLOB</code> 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</code> using
* an SQL <code>locator(BLOB)</code>, which means that a
* <code>Blob</code> object contains a logical pointer to the
* SQL <code>BLOB</code> data rather than the data itself.
* A <code>Blob</code> 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</code> and <code>setBlob</code> allow a programmer to
* access an SQL <code>BLOB</code> value.
* The <code>Blob</code> interface provides methods for getting the
* length of an SQL <code>BLOB</code> (Binary Large Object) value,
* for materializing a <code>BLOB</code> value on the client, and for
* determining the position of a pattern of bytes within a
* <code>BLOB</code> value. In addition, this interface has methods for updating
* a <code>BLOB</code> value.
* <p>
* All methods on the <code>Blob</code> 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</code> value
* designated by this <code>Blob</code> object.
* @return length of the <code>BLOB</code> in bytes
* @exception SQLException if there is an error accessing the
* length of the <code>BLOB</code>
* @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</code>
* value that this <code>Blob</code> object represents, as an array of
* bytes. This <code>byte</code> array contains up to <code>length</code>
* consecutive bytes starting at position <code>pos</code>.
*
* @param pos the ordinal position of the first byte in the
* <code>BLOB</code> 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</code>
* consecutive bytes from the <code>BLOB</code> value designated
* by this <code>Blob</code> object, starting with the
* byte at position <code>pos</code>
* @exception SQLException if there is an error accessing the
* <code>BLOB</code> 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</code> value designated by this
* <code>Blob</code> instance as a stream.
*
* @return a stream containing the <code>BLOB</code> data
* @exception SQLException if there is an error accessing the
* <code>BLOB</code> 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</code> begins within the <code>BLOB</code>
* value that this <code>Blob</code> object represents. The
* search for <code>pattern</code> begins at position
* <code>start</code>.
*
* @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</code> 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</code> value
* designated by this <code>Blob</code> object at which
* <code>pattern</code> begins. The search begins at position
* <code>start</code>.
*
* @param pattern the <code>Blob</code> object designating
* the <code>BLOB</code> value for which to search
* @param start the position in the <code>BLOB</code> 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</code> 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</code> value that
* this <code>Blob</code> object represents, starting at position
* <code>pos</code>, and returns the number of bytes written.
* The array of bytes will overwrite the existing bytes
* in the <code>Blob</code> object starting at the position
* <code>pos</code>. If the end of the <code>Blob</code> value is reached
* while writing the array of bytes, then the length of the <code>Blob</code>
* value will be increased to accomodate the extra bytes.
* <p>
* <b>Note:</b> If the value specified for <code>pos</code>
* is greater then the length+1 of the <code>BLOB</code> value then the
* behavior is undefined. Some JDBC drivers may throw a
* <code>SQLException</code> while other drivers may support this
* operation.
*
* @param pos the position in the <code>BLOB</code> object at which
* to start writing; the first position is 1
* @param bytes the array of bytes to be written to the <code>BLOB</code>
* value that this <code>Blob</code> object represents
* @return the number of bytes written
* @exception SQLException if there is an error accessing the
* <code>BLOB</code> 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</code> array to the
* <code>BLOB</code> value that this <code>Blob</code> object represents
* and returns the number of bytes written.
* Writing starts at position <code>pos</code> in the <code>BLOB</code>
* value; <code>len</code> bytes from the given byte array are written.
* The array of bytes will overwrite the existing bytes
* in the <code>Blob</code> object starting at the position
* <code>pos</code>. If the end of the <code>Blob</code> value is reached
* while writing the array of bytes, then the length of the <code>Blob</code>
* value will be increased to accomodate the extra bytes.
* <p>
* <b>Note:</b> If the value specified for <code>pos</code>
* is greater then the length+1 of the <code>BLOB</code> value then the
* behavior is undefined. Some JDBC drivers may throw a
* <code>SQLException</code> while other drivers may support this
* operation.
*
* @param pos the position in the <code>BLOB</code> object at which
* to start writing; the first position is 1
* @param bytes the array of bytes to be written to this <code>BLOB</code>
* object
* @param offset the offset into the array <code>bytes</code> at which
* to start reading the bytes to be set
* @param len the number of bytes to be written to the <code>BLOB</code>
* value from the array of bytes <code>bytes</code>
* @return the number of bytes written
* @exception SQLException if there is an error accessing the
* <code>BLOB</code> 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</code>
* value that this <code>Blob</code> object represents. The stream begins
* at position <code>pos</code>.
* The bytes written to the stream will overwrite the existing bytes
* in the <code>Blob</code> object starting at the position
* <code>pos</code>. If the end of the <code>Blob</code> value is reached
* while writing to the stream, then the length of the <code>Blob</code>
* value will be increased to accomodate the extra bytes.
* <p>
* <b>Note:</b> If the value specified for <code>pos</code>
* is greater then the length+1 of the <code>BLOB</code> value then the
* behavior is undefined. Some JDBC drivers may throw a
* <code>SQLException</code> while other drivers may support this
* operation.
*
* @param pos the position in the <code>BLOB</code> value at which
* to start writing; the first position is 1
* @return a <code>java.io.OutputStream</code> object to which data can
* be written
* @exception SQLException if there is an error accessing the
* <code>BLOB</code> 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</code> value that this <code>Blob</code>
* object represents to be <code>len</code> bytes in length.
* <p>
* <b>Note:</b> If the value specified for <code>pos</code>
* is greater then the length+1 of the <code>BLOB</code> value then the
* behavior is undefined. Some JDBC drivers may throw a
* <code>SQLException</code> while other drivers may support this
* operation.
*
* @param len the length, in bytes, to which the <code>BLOB</code> value
* that this <code>Blob</code> object represents should be truncated
* @exception SQLException if there is an error accessing the
* <code>BLOB</code> 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</code> object and releases the resources that
* it holds. The object is invalid once the <code>free</code>
* method is called.
*<p>
* After <code>free</code> has been called, any attempt to invoke a
* method other than <code>free</code> will result in a <code>SQLException</code>
* being thrown. If <code>free</code> is called multiple times, the subsequent
* calls to <code>free</code> are treated as a no-op.
*<p>
*
* @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</code> object that contains a partial <code>Blob</code> 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</code> is at position 1
* @param length the length in bytes of the partial value to be retrieved
* @return <code>InputStream</code> through which the partial <code>Blob</code> 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</code> or if pos + length is greater than the number of bytes
* in the <code>Blob</code>
*
* @exception SQLFeatureNotSupportedException if the JDBC driver does not support
* this method
* @since 1.6
*/
InputStream getBinaryStream(long pos, long length) throws SQLException;
}