/*
* @(#)Blob.java 1.28 03/12/19
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.sql;
/**
* The representation (mapping) in
* the JavaTM programming
* language of an SQL
* BLOB
value. An SQL 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 Blob
using
* an SQL locator(BLOB)
, which means that a
* Blob
object contains a logical pointer to the
* SQL BLOB
data rather than the data itself.
* A Blob
object is valid for the duration of the
* transaction in which is was created.
*
*
Methods in the interfaces {@link ResultSet},
* {@link CallableStatement}, and {@link PreparedStatement}, such as
* getBlob
and setBlob
allow a programmer to
* access an SQL BLOB
value.
* The Blob
interface provides methods for getting the
* length of an SQL BLOB
(Binary Large Object) value,
* for materializing a BLOB
value on the client, and for
* determining the position of a pattern of bytes within a
* BLOB
value. In addition, this interface has methods for updating
* a BLOB
value.
*
* @since 1.2
*/
public interface Blob {
/**
* Returns the number of bytes in the BLOB
value
* designated by this Blob
object.
* @return length of the BLOB
in bytes
* @exception SQLException if there is an error accessing the
* length of the BLOB
* @since 1.2
*/
long length() throws SQLException;
/**
* Retrieves all or part of the BLOB
* value that this Blob
object represents, as an array of
* bytes. This byte
array contains up to length
* consecutive bytes starting at position pos
.
*
* @param pos the ordinal position of the first byte in the
* BLOB
value to be extracted; the first byte is at
* position 1
* @param length the number of consecutive bytes to be copied
* @return a byte array containing up to length
* consecutive bytes from the BLOB
value designated
* by this Blob
object, starting with the
* byte at position pos
* @exception SQLException if there is an error accessing the
* BLOB
value
* @see #setBytes
* @since 1.2
*/
byte[] getBytes(long pos, int length) throws SQLException;
/**
* Retrieves the BLOB
value designated by this
* Blob
instance as a stream.
*
* @return a stream containing the BLOB
data
* @exception SQLException if there is an error accessing the
* BLOB
value
* @see #setBinaryStream
* @since 1.2
*/
java.io.InputStream getBinaryStream () throws SQLException;
/**
* Retrieves the byte position at which the specified byte array
* pattern
begins within the BLOB
* value that this Blob
object represents. The
* search for pattern
begins at position
* 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
* BLOB
* @since 1.2
*/
long position(byte pattern[], long start) throws SQLException;
/**
* Retrieves the byte position in the BLOB
value
* designated by this Blob
object at which
* pattern
begins. The search begins at position
* start
.
*
* @param pattern the Blob
object designating
* the BLOB
value for which to search
* @param start the position in the 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
* BLOB
value
* @since 1.2
*/
long position(Blob pattern, long start) throws SQLException;
// -------------------------- JDBC 3.0 -----------------------------------
/**
* Writes the given array of bytes to the BLOB
value that
* this Blob
object represents, starting at position
* pos
, and returns the number of bytes written.
*
* @param pos the position in the BLOB
object at which
* to start writing
* @param bytes the array of bytes to be written to the BLOB
* value that this Blob
object represents
* @return the number of bytes written
* @exception SQLException if there is an error accessing the
* BLOB
value
* @see #getBytes
* @since 1.4
*/
int setBytes(long pos, byte[] bytes) throws SQLException;
/**
* Writes all or part of the given byte
array to the
* BLOB
value that this Blob
object represents
* and returns the number of bytes written.
* Writing starts at position pos
in the BLOB
* value; len
bytes from the given byte array are written.
*
* @param pos the position in the BLOB
object at which
* to start writing
* @param bytes the array of bytes to be written to this BLOB
* object
* @param offset the offset into the array bytes
at which
* to start reading the bytes to be set
* @param len the number of bytes to be written to the BLOB
* value from the array of bytes bytes
* @return the number of bytes written
* @exception SQLException if there is an error accessing the
* BLOB
value
* @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 BLOB
* value that this Blob
object represents. The stream begins
* at position pos
.
*
* @param pos the position in the BLOB
value at which
* to start writing
* @return a java.io.OutputStream
object to which data can
* be written
* @exception SQLException if there is an error accessing the
* BLOB
value
* @see #getBinaryStream
* @since 1.4
*/
java.io.OutputStream setBinaryStream(long pos) throws SQLException;
/**
* Truncates the BLOB
value that this Blob
* object represents to be len
bytes in length.
*
* @param len the length, in bytes, to which the BLOB
value
* that this Blob
object represents should be truncated
* @exception SQLException if there is an error accessing the
* BLOB
value
* @since 1.4
*/
void truncate(long len) throws SQLException;
}